SCJP认证考试题集
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310-055SCJIP认证考试题集
Question 1
Given:
11.public interface Status {
12. /*insert code here */ int MY_VALUE = 10;
13. }
Whichthree are valid on line 12? (Choose three.)
A.final
B.static
C.native
D.public
E.private
F.abstract
G.protected
Answer:ABD
Question 2
Given:
10.public class Bar {
11.staticvoid foo(int...x) {
12. //insert code here
13. }
14. }
Whichtwo code fragments, inserted independently at line 12, will allow
theclass to compile? (Choose two.)
A.foreach(x) System.out.println(z);
B. for(int z : x)System.out.println(z); abcd
C.while( x.hasNext()) System.out.println( x.next());
D.for( int i=0; i< x.length; i++ ) System.out.println(x[i]);
Answer:BD
Question 3
Given:
11.public class Test {
12.public static void main(String [] args) {
13.int x =5;
14.boolean b1 = true;
15.boolean b2 = false;
16.
17.if((x==4)&& !b2)
18.System.out.print(”l “);
19.System.out.print(”2 “);
20. if((b2 = true) && b1)
21.System.out.print(”3 “);
22. }
23. }
Whatis the result?
A. 2
B. 3
C. 1 2
D. 2 3
E. 1 23
F.Compilation fails.
G. Auexceptional is thrown at runtime.
Answer:D
Question 4
4.Given:
31. //some code here
32.try {
33. //some code here
34. }catch (SomeException se) {
35. //some code here
36. }finally {
37. //some code here
38. }
Underwhich three circumstances will the code on line 37 be executed?
(Choosethree.)
A. Theinstance gets garbage collected.
B. Thecode on line 33 throws an exception.
C. Thecode on line 35 throws an exception.
D. Thecode on line 31 throws an exception.
E. Thecode on line 33 executes successfully.
Answer:BCE
lQuestion 5
Given:
10.interface Foo {}
11.class Alpha implements Foo { }
12.class Beta extends Alpha {}
13.class Delta extends Beta {
14.public static void main( String[] args) {
15.Beta x = new Beta();
16. //insert code here
17. }
18. }
Whichcode, inserted at line 16, will cause a
java.lang.ClassCastException?
A.Alpha a = x;
B. Foof= (Delta)x;
C. Foof= (Alpha)x;
D. Beta b = (Beta)(Alpha)x;
Answer:B
Question 6
Given:
? d isa valid, non-null Date object
? dfis a valid, non-null DateFormat object set to the
currentlocale
Whatoutputs the current locales country name and the appropriate
versionof d’s date?
A.Locale loc = Locale.getLocale();
System.out.println(loc.getDisplayCountry()
+ “ “+ df.format(d));
B.Locale loc = Locale.getDefault();
System.out.println(loc.getDisplayCountry()
+ “ “ + df.format(d));
C.Locale bc = Locale.getLocale();
System.out.println(loc.getDisplayCountry()
+ “ “+ df.setDateFormat(d));
D.Locale loc = Locale.getDefault();
System.out.println(loc.getDispbayCountry()
+ “ “+ df.setDateFormat(d));
Answer:B
Question 7
Given:
20.public class CreditCard {
21.
22.private String cardlD;
23.private Integer limit;
24.public String ownerName;
25.
26.public void setCardlnformation(String cardlD,
27.String ownerName,
28.Integer limit) {
29.this.cardlD = cardlD;
30.this.ownerName = ownerName;
31.this.limit = limit;
32. }
33. }
Whichis true?
A. Theclass is fully encapsulated.
B. Thecode demonstrates polymorphism.
C. TheownerName variable breaks encapsulation.
D. ThecardlD and limit variables break polymorphism.
E. ThesetCardlnformation method breaks encapsulation.
Answer:C
Question 8
Assumethat country is set for each class.
Given:
10.public class Money {
11.private String country, name;
12.public getCountry() { return country; }
13.}
and:
24.class Yen extends Money {
25.public String getCountry() { return super.country; }
26. }
27.
28.class Euro extends Money {
29.public String getCountry(String timeZone) {
30.return super.getCountry();
31. }
32. }
Whichtwo are correct? (Choose two.)
A. Yenreturns correct values.
B.Euro returns correct values.
C. Anexception is thrown at runtime.
D. Yenand Euro both return correct values.
E.Compilation fails because of an error at line 25.
F.Compilation fails because of an error at line 30.
Answer:BE
Question 9 abcd
WhichMan class properly represents the relationship “Man has a best
friendwho is a Dog”?
A.class Man extends Dog { }
B.class Man implements Dog { }
C.class Man { private BestFriend dog; }
D.class Man { private Dog bestFriend; }
E.class Man { private Dog<bestFriend> }
F.class Man { private BestFriend<dog> }
Answer:D
Question 10
Given:
11.public class Person {
12.private name;
13.public Person(String name) {
14.this.name = name;
15. }
16.public int hashCode() {
17.return 420;
18. }
19. }
Whichis true?
A. Thetime to find the value from HashMap with a Person key depends
on thesize of the map.
B.Deleting a Person key from a HashMap will delete all map entries for
allkeys of type Person.
C.Inserting a second Person object into a HashSet will cause the first
Personobject to be removed as a duplicate.
D. Thetime to determine whether a Person object is contained in a
HashSetis constant and does NOT depend on the size of the map.
Answer:A
Question 11
Given:
23.Object [] myObjects = {
24.new integer(12),
25.new String(”foo”),
26.new integer(5),
27.new Boolean(true)
28. };
29.Arrays.sort(myObjects);
30.for( int i=0; i<myObjects.length; i++) {
31.System.out.print(myObjects[i].toString());
32.System.out.print(” “);
33. }
Whatis the result?
A.Compilation fails due to an error in line 23.
B.Compilation fails due to an error in line 29.
C. AClassCastException occurs in line 29.
D. AClassCastException occurs in line 31.
E. Thevalue of all four objects prints in natural order.
Answer:C
Question 12
12.Given:
13.public class Pass {
14.public static void main(String [1 args) {
15.int x 5;
16.Pass p = new Pass();
17.p.doStuff(x);
18.System.out.print(” main x = “+ x);
19. }
20.
21.void doStuff(int x) {
22.System.out.print(” doStuff x = “+ x++);
23. }
24. }
Whatis the result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C.doStuffx = 6 main x = 6
D. doStuffx= 5 main x = 5
E.doStuffx = 5 main x = 6
F.doStuffx = 6 main x = 5
Answer:D
Question 13
Given:
10.package com.sun.scjp;
11.public class Geodetics {
12.public static final double DIAMETER = 12756.32; // kilometers
13. }
Whichtwo correctly access the DIAMETER member of the Geodetics
class?(Choose two.)
A.import com.sun.scjp.Geodetics;
publicclass TerraCarta {
publicdouble halfway()
{return Geodetics.DIAMETER/2.0; } }
B.import static com.sun.scjp.Geodetics;
publicclass TerraCarta {
publicdouble halfway() { return DIAMETER/2.0; } }
C.import static com.sun.scjp.Geodetics. *;
publicclass TerraCarta {
publicdouble halfway() { return DIAMETER/2.0; } }
D.package com.sun.scjp;
publicclass TerraCarta {
publicdouble halfway() { return DIAMETER/2.0; } }
Answer:AC
Question 14
Given:
10.class Nav{
11.public enum Direction { NORTH, SOUTH, EAST, WEST }
12. }
13.public class Sprite{
14. //insert code here
15. }
Whichcode, inserted at line 14, allows the Sprite class to compile?
A.Direction d = NORTH;
B.Nav.Direction d = NORTH;
C.Direction d = Direction.NORTH;
D.Nav.Direction d = Nav.Direction.NORTH;
Answer:D
Question 15
Given:
10.interface Foo { int bar(); }
11.public class Sprite {
12.public int fubar( Foo foo) { return foo.bar(); }
13.public void testFoo() {
14.fubar(
15. //insert code here
16.);
17. }
18. }
Whichcode, inserted at line 15, allows the class Sprite to compile?
A. Foo{ public int bar() { return 1; } }
B. newFoo { public int bar() { return 1; } }
C.newFoo() { public int bar(){return 1; } }
D. newclass Foo { public int bar() { return 1; } }
Answer:C
Question 16
Clickthe Exhibit button.
10.interface Foo {
11.int bar();
12. }
13.
14.public class Beta {
15.
16.class A implements Foo {
17.public int bar() { return 1; }
18. }
19.
20.public int fubar( Foo foo) { return foo.bar(); }
21.
22.public void testFoo() {
23.
24.class A implements Foo {
25.public int bar() { return 2; }
26. }
27.
28.System.out.println( fubar( new A()));
29. }
30.
31.public static void main( String[] argv) {
32.new Beta().testFoo();
33. }
34. }
Whichthree statements are true? (Choose three.)
A.Compilation fails.
B. Thecode compiles and the output is 2.
C. Iflines 16, 17 and 18 were removed, compilation would fail.
D. Iflines 24, 25 and 26 were removed, compilation would fail.
E. Iflines 16, 17 and 18 were removed, the code would compile and
theoutput would be 2.
F. Iflines 24, 25 and 26 were removed, the code would compile and
theoutput would be 1.
Answer:BEF
Question 17
Given:
1.package sun.scjp;
2.public enum Color { RED, GREEN, BLUE }
1.package sun.beta;
2. //insert code here
3.public class Beta {
4.Color g = GREEN;
5.public static void main( String[] argv)
6. {System.out.println( GREEN); }
7. }
Theclass Beta and the enum Color are in different packages.
Whichtwo code fragments, inserted individually at line 2 of the Beta
declaration,will allow this code to compile? (Choose two.)
A.import sun.scjp.Color.*;
B.import static sun.scjp.Color.*;
C.import sun.scjp.Color; import static sun.scjp.Color.*;
D.import sun.scjp.*; import static sun.scjp.Color.*;
E.import sun.scjp.Color; import static sun.scjp.Color.GREEN;
Answer:CE
Question 18
Given:
1.public interface A {
2.String DEFAULT_GREETING = “Hello World”;
3.public void method1();
4. }
Aprogrammer wants to create an interface called B that has A as its
parent.Which interface declaration is correct?
A.public interface B extends A { }
B.public interface B implements A {}
C.public interface B instanceOf A {}
D. publicinterface B inheritsFrom A { }
Answer:A
Question 19
Given:
1.class TestA {
2.public void start() { System.out.println(”TestA”); }
3. }
4.public class TestB extends TestA {
5.public void start() { System.out.println(”TestB”); }
6.public static void main(String[] args) {
7.((TestA)new TestB()).start();
8. }
9. }
Whatis the result?
A.TestA
B.TestB
C.Compilation fails.
D. Anexception is thrown at runtime.
Answer:B
Question 20
Given:
1.interface TestA { String toString(); }
2.public class Test {
3.public static void main(String[] args) {
4.System.out.println(new TestA() {
5.public String toString() { return “test”; }
6. });
7. }
8. }
Whatis the result?
A.test
B.null
C. Anexception is thrown at runtime.
D.Compilation fails because of an error in line 1.
E.Compilation fails because of an error in line 4.
F.Compilation fails because of an error in line 5.
Answer:A
Question 21
Given:
11.public abstract class Shape {
12.int x;
13.int y;
14.public abstract void draw();
15.public void setAnchor(int x, int y) {
16.this.x = x;
17.this.y = y;
18. }
19. }
and aclass Circle that extends and fully implements the Shape class.
Whichis correct?
A.Shape s = new Shape();
s.setAnchor(10,10);
s.draw();
B.Circle c = new Shape();
c.setAnchor(10,10);
c.draw();
C.Shape s = new Circle();
s.setAnchor(10,10);
s.draw();
D.Shape s = new Circle();
s->setAnchor(10,10);
s->draw();
E.Circle c = new Circle();
c.Shape.setAnchor(10,10);
c.Shape.draw();
Answer:C
Question 22
Given:
10.abstract public class Employee {
11.protected abstract double getSalesAmount();
12.public double getCommision() {
13.return getSalesAmount() * 0.15;
14. }
15. }
16.class Sales extends Employee {
17. //insert method here
18. }
Whichtwo methods, inserted independently at line 17, correctly
completethe Sales class? (Choose two.)
A.double getSalesAmount() { return 1230.45; }
B.public double getSalesAmount() { return 1230.45; }
C.private double getSalesAmount() { return 1230.45; }
D.protected double getSalesAmount() { return 1230.45; }
Answer:BD
Question 23
Given:
10.interface Data { public void load(); }
11.abstract class Info { public abstract void load(); }
Whichclass correctly uses the Data interface and Info class?
A.public class Employee extends Info implements Data {
publicvoid load() { /*do something*/ }
}
B.public class Employee implements Info extends Data {
publicvoid load() { /*do something*/ }
}
C.public class Employee extends Info implements Data {
publicvoid load() { /*do something */ }
publicvoid Info.load() { /*do something*/ }
}
D.public class Employee implements Info extends Data {
publicvoid Data.load() { /*d something */ }
publicvoid load() { /*do something */ }
}
E.public class Employee implements Info extends Data {
publicvoid load() { /*do something */ }
publicvoid Info.load(){ /*do something*/ }
}
F.public class Employee extends Info implements Data{
publicvoid Data.load() { /*do something*/ }
publicvoid Info.load() { /*do something*/ }
}
Answer:A
Question 24
Given:
11.public abstract class Shape {
12.private int x;
13.private int y;
14.public abstract void draw();
15.public void setAnchor(int x, int y) {
16.this.x = x;
17.this.y = y;
18. }
19. }
Whichtwo classes use the Shape class correctly? (Choose two.)
A.public class Circle implements Shape {
privateint radius;
}
B.public abstract class Circle extends Shape {
privateint radius;
}
C.public class Circle extends Shape {
privateint radius;
publicvoid draw();
}
D.public abstract class Circle implements Shape {
privateint radius;
publicvoid draw();
}
E.public class Circle extends Shape {
privateint radius;
publicvoid draw() {/* code here */}
}
F.public abstract class Circle implements Shape {
privateint radius;
publicvoid draw() { / code here */ }
}
Answer:BE
Question 25
Whichtwo classes correctly implement both the java.lang.Runnable
andthe java.lang.Clonable interfaces? (Choose two.)
A.public class Session
implementsRunnable, Clonable {
publicvoid run();
publicObject clone();
}
B.public class Session
extendsRunnable, Clonable {
publicvoid run() { / do something */ }
publicObject clone() { / make a copy */ }
}
C.public class Session
implementsRunnable, Clonable {
publicvoid run() { / do something */ }
publicObject clone() { /* make a copy */ }
}
D.public abstract class Session
implementsRunnable, Clonable {
publicvoid run() { / do something */ }
publicObject clone() { /*make a copy */ }
}
E.public class Session
implementsRunnable, implements Clonable {
publicvoid run() { / do something */ }
publicObject clone() { / make a copy */ }
}
Answer:CD
Question26
Clickthe Exhibit button.
1.public class GoTest {
2.public static void main(String[] args) {
3.Sente a = new Sente(); a.go();
4.Goban b = new Goban(); b.go();
5.Stone c = new Stone(); c.go();
6. }
7. }
8.
9.class Sente implements Go {
10.public void go() { System.out.println(”go in Sente.”); }
11. }
12.
13.class Goban extends Sente {
14.public void go() { System.out.println(”go in Goban”); }
15. }
16.
17.class Stone extends Goban implements Go { }
18.
19.interface Go { public void go(); }
Whatis the result?
A. goin Goban
go inSente
go inSente
B. goin Sente
go inSente
go inGoban
C. goin Sente
go inGoban
go inGoban
D. goin Goban
go inGoban
go inSente
E.Compilation fails because of an error in line 17.
Answer:C
Question 27
Given:
11.public static void parse(String str) {
12.try {
13.float f= Float.parseFloat(str);
14. }catch (NumberFormatException nfe) {
15. f=0;
16. }finally {
17.System.out.println(f);
18. }
19. }
20.public static void main(String[] args) {
21.parse(”invalid”);
22. }
Whatis the result?
A. 0.0
B.Compilation fails.
C. AParseException is thrown by the parse method at runtime.
D. ANumberFormatException is thrown by the parse method at
runtime.
Answer:B
Question 28
Clickthe Exhibit button.
1.public class Test {
2. intx= 12;
3.public void method(int x) {
4.x+=x;
5.System.out.println(x);
6. }
7. }
Given:
34.Test t = new Test();
35.t.method(5);
Whatis the output from line 5 of the Test class?
A. 5
B. 10
C. 12
D. 17
E. 24
Answer:B
Question 28
Given:
55.int []x= {1, 2,3,4, 5};
56.inty[] =x;
57.System.out.println(y[2]);
Whichis true?
A.Line 57 will print the value 2.
B.Line 57 will print the value 3.
C.Compilation will fail because of an error in line 55.
D.Compilation will fail because of an error in line 56.
Answer:B
Question 30
Given:
35.String #name = “Jane Doe”;
36.int$age=24;
37.Double_height = 123.5;
38.double~temp = 37.5;
Whichtwo are true? (Choose two.)
A.Line 35 will not compile.
B.Line 36 will not compile.
C.Line 37 will not compile.
D.Line 38 will not compile.
Answer:AD
Question 31
Whichtwo code fragments correctly create and initialize a static array
of intelements? (Choose two.)
A.static final int[] a = { 100,200 };
B.static final int[] a;
static{ a=new int[2]; a[0]=100; a[1]=200; }
C.static final int[] a = new int[2] { 100,200 };
D.static final int[] a;
staticvoid init() { a = new int[3]; a[0]=100; a[1]=200; }
Answer:AB
Question 32
Given:
11.public class Ball {
12.public enum Color { RED, GREEN, BLUE };
13.public void foo() {
14. //insert code here
15. {System.out.println(c); }
16. }
17. }
Whichcode inserted at line 14 causes the foo method to print RED,
GREEN,and BLUE?
A.for( Color c : Color.values())
B.for( Color c = RED; c <= BLUE; c++)
C.for( Color c; c.hasNext() ; c.next())
D.for( Color c = Color[0]; c <= Color[2]; c++)
E.for( Color c = Color.RED; c <= Color.BLUE; c++)
Answer:A
Question 33
Given:
10.public class Fabric
11.public enum Color {
12.RED(0xff0000), GREEN(0x00ff00), BLUE(0x0000ff);
13.private final int rgb;
14.Color( int rgb) { this.rgb = rgb; }
15.public int getRGB() { return rgb; }
16. };
17.public static void main( String[] argv) {
18. //insert code here
19. }
20. }
Whichtwo code fragments, inserted independently at line 18, allow the
Fabricclass to compile? (Choose two.)
A.Color skyColor = BLUE;
B.Color treeColor = Color.GREEN;
C.Color purple = new Color( 0xff00ff);
D. if(RED.getRGB() < BLUE.getRGB() ) {}
E.Color purple = Color.BLUE + Color.RED;
F. if(Color.RED.ordinal() < Color.BLUE.ordinal() ) {}
Answer:BF
Question 34
Given:
11.public enum Title {
12.MR(”Mr.”), MRS(”Mrs.”), MS(”Ms.”);
13.private final String title;
14.private Title(String t) { title = t; }
15.public String format(String last, String first) {
16.return title + “ “ + first + “ “ + last;
17. }
18. }
19.public static void main(String[] args) {
20.System.out.println(Title.MR.format(”Doe”, “John”));
21. }
Whatis the result?
A. Mr.John Doe
B. Anexception is thrown at runtime.
C.Compilation fails because of an error in line 12.
D.Compilation fails because of an error in line 15.
E.Compilation fails because of an error in line 20.
Answer:A
Question 35
Given:
11.public static void main(String[] args) {
12.Object obj =new int[] { 1,2,3 };
13.int[] someArray = (int[])obj;
14.for (int i: someArray) System.out.print(i +“ “)
15. }
‘What is the result?
A. 1 23
B.Compilation fails because of an error in line 12.
C.Compilation fails because of an error in line 13.
D.Compilation fails because of an error in line 14.
E. AClassCastException is thrown at runtime.
Answer:A
Question 36
Given:
10.class Foo {
11.static void alpha() { /* more code here */ }
12.void beta() { /* more code here */ }
13. }
Whichtwo are true? (Choose two.)
A.Foo.beta() is a valid invocation of beta().
B.Foo.alpha() is a valid invocation of alpha().
C.Method beta() can directly call method alpha().
D.Method alpha() can directly call method beta().
Answer:BC
Question 37
Aprogrammer needs to create a logging method that can accept an
arbitrarynumber of arguments. For example, it may be called in these
ways:
logIt(”logmessage 1 “);
logIt(”log message2”,”log message3”);
logIt(”log message4”, “log message5”, “log message6);
Whichdeclaration satisfies this requirement?
A.public void logIt(String * msgs)
B.public void logIt(String [] msgs)
C.public void logIt(String... msgs)
D.public void logIt(String msg1, String msg2, String msg3)
Answer:C
Question 38
Aprogrammer is designing a class to encapsulate the information
aboutan inventory item. A JavaBeans component is needed to
dothis. The Inventoryltem class has private instance variables to store
theitem information:
10.private int itemId;
11.private String name;
12.private String description;
Whichmethod signature follows the JavaBeans naming standards for
modifyingthe itemld instance variable?
A.itemID(int itemId)
B.update(int itemId)
C.setItemId(int itemId)
D.mutateItemId(int itemId)
E.updateItemID(int itemId)
Answer:C
Question 39
Clickthe Exhibit button.
1.public class A {
2.
3.private int counter = 0;
4.
5.public static int getInstanceCount() {
6.return counter;
7. }
8.
9.public A() {
10.counter++;
11. }
12.
13. }
Giventhis code from Class B:
25.Aa1 =new A();
26. Aa2 =new A();
27. Aa3 =new A();
28.System.out.printIn(A.getInstanceCount() );
Whatis the result?
A.Compilation of class A fails.
B.Line 28 prints the value 3 to System.out.
C.Line 28 prints the value 1 to System.out.
D. Aruntime error occurs when line 25 executes.
E.Compilation fails because of an error on line 28.
Answer:A
Question 40
AJavaBeans component has the following field:
11.private boolean enabled;
Whichtwo pairs of method declarations follow the JavaBeans standard
foraccessing this field? (Choose two.)
A.public void setEnabled( boolean enabled)
publicboolean getEnabled()
B.public void setEnabled( boolean enabled)
publicvoid isEnabled()
C.public void setEnabled( boolean enabled)
publicboolean isEnabled()
D.public boolean setEnabled( boolean enabled)
publicboolean getEnabled()
Answer:AC
Question 41
41.Given:
10.class One {
11.public One foo() { return this; }
12. }
13.class Two extends One {
14.public One foo() { return this; }
15. }
16.class Three extends Two {
17. //insert method here
18. }
Whichtwo methods, inserted individually, correctly complete the Three
class?(Choose two.)
A.public void foo() { }
B.public int foo() { return 3; }
C.public Two foo() { return this; }
D.public One foo() { return this; }
E.public Object foo() { return this; }
Answer:CD
Question 42
Given:
10.class One {
11.void foo() {}
12. }
13.class Two extends One {
14.//insert method here
15. }
Whichthree methods, inserted individually at line 14, will correctly
completeclass Two? (Choose three.)
A. intfoo() { /* more code here */ }
B.void foo() { /* more code here */ }
C.public void foo() { /* more code here */ }
D.private void foo() { /* more code here */ }
E.protected void foo() { /* more code here */ }
Answer:BCE
Question 43
Clickthe Exhibit button.
1.public interface A {
2.public void doSomething(String thing);
3. }
1.public class AImpl implements A {
2.public void doSomething(String msg) { }
3. }
1.public class B {
2.public A doit() {
3. //more code here
4. }
5.
6.public String execute() {
7. //more code here
8. }
9. }
1.public class C extends B {
2.public AImpl doit() {
3. //more code here
4. }
5.
6.public Object execute() {
7. //more code here
8. }
9. }
Whichstatement is true about the classes and interfaces in the
exhibit?
A.Compilation will succeed for all classes and interfaces.
B.Compilation of class C will fail because of an error in line 2.
C.Compilation of class C will fail because of an error in line 6.
D.Compilation of class AImpl will fail because of an error in line 2.
Answer:C
Question 44
Clickthe Exhibit button.
1.public class A {
2.public String doit(int x, int y) {
3.return “a”;
4. }
5.
6.public String doit(int... vals) {
7.return “b”;
8. }
9. }
Given:
25. Aa=new A();
26.System.out.println(a.doit(4, 5));
Whatis the result?
A.Line 26 prints “a” to System.out.
B.Line 26 prints ‘b” to System.out.
C. Anexception is thrown at line 26 at runtime.
D.Compilation of class A will fail due to an error in line 6.
Answer:A
Question 45
Given:
1.public class A {
2.public void doit() {
3. }
4.public String doit() {
5.return “a”;
6. }
7.public double doit(int x) {
8.return 1.0;
9. }
10.}
Whatis the result?
A. Anexception is thrown at runtime.
B.Compilation fails because of an error in line 7.
C.Compilation fails because of an error in line 4.
D.Compilation succeeds and no runtime errors with class A occur.
Answer:C
Question 46
46.Given:
10.class Line {
11.public static class Point { }
12. }
13.
14.class Triangle {
15. //insert code here
16. }
Whichcode, inserted at line 15, creates an instance of the Point class
definedin Line?
A.Point p = new Point();
B.Line.Point p = new Line.Point();
C. ThePoint class cannot be instatiated at line 15.
D.Line 1 = new Line() ; 1.Point p = new 1.Point();
Answer:B
Question 47
Given:
10.class Line {
11.public class Point { public int x,y; }
12.public Point getPoint() { return new Point(); }
13. }
14.class Triangle {
15.public Triangle() {
16. //insert code here
17. }
18. }
Whichcode, inserted at line 16, correctly retrieves a local instance of a
Pointobject?
A.Point p = Line.getPoint();
B.Line.Point p = Line.getPoint();
C.Point p = (new Line()).getPoint();
D.Line.Point p = (new Line()).getPoint();
Answer:D
Question 48
Given:
10.class One {
11.public One() { System.out.print(1); }
12. }
13.class Two extends One {
14.public Two() { System.out.print(2); }
15. }
16.class Three extends Two {
17.public Three() { System.out.print(3); }
18. }
19.public class Numbers{
20.public static void main( String[] argv) { new Three(); }
21. }
Whatis the result when this code is executed?
A. 1
B. 3
C. 123
D. 321
E. Thecode rims with no output.
Answer:C
Question 49
Clickthe Exhibit button.
11.class Person {
12.String name = “No name’;
13.public Person(String nm) { name = nm; }
14. }
15.
16.class Employee extends Person {
17.String emplD = “0000”;
18.public Employee(String id) { empID = id; }
19. }
20.
21.public class EmployeeTest {
22.public static void main(String[] args) {
23.Employee e = new Employee(”4321”);
24.System.out.println(e.empID);
25. }
26. }
Whatis the result?
A.4321
B.0000
C. Anexception is thrown at runtime.
D.Compilation fails because of an error in line 18.
Answer:D
Question 50
Given:
1. publicclass Plant {
2.private String name;
3.public Plant(String name) { this.name = name; }
4.public String getName() { return name; }
5. }
1.public class Tree extends Plant {
2.public void growFruit() { }
3.public void dropLeaves() { }
4. }
Whichis true?
A. Thecode will compile without changes.
B. Thecode will compile if public Tree() { Plant(); } is added to the
Treeclass.
C. Thecode will compile if public Plant() { Tree(); } is added to the
Plantclass.
D. Thecode will compile if public Plant() { this(”fern”); } is added to
thePlant class.
E. Thecode will compile if public Plant() { Plant(”fern”); } is added to
thePlant class.
Answer:D
Question 51
Clickthe Exhibit button.
11.public class Bootchy {
12.int bootch;
13.String snootch;
14.
15.public Bootchy() {
16.this(”snootchy”);
17.System.out.print(”first “);
18. }
19.
20.public Bootchy(String snootch) {
21.this(420, “snootchy”);
22.System.out.print(”second “);
23. }
24.
25.public Bootchy(int bootch, String snootch) {
26.this.bootch = bootch;
27.this.snootch = snootch;
28.System.out.print(”third “);
29. }
30.
31.public static void main(String[] args) {
32.Bootchy b = new Bootchy();
33.System.out.print(b.snootch +“ “ + b.bootch);
34. }
35. }
Whatis the result?
A.snootchy 420 third second first
B.snootchy 420 first second third
C.first second third snootchy 420
D.third second first siiootchy 420
E.third first second snootchy 420
F.first second first third snootchy 420
Answer:D
Question 52
Given:
11.public class Test {
12.public enum Dogs {collie, harrier, shepherd};
13.public static void main(String [] args) {
14.Dogs myDog = Dogs.shepherd;
15.switch (myDog) {
16.case collie:
17.System.out.print(”collie “);
18.case default:
19.System.out.print(”retriever “);
20. caseharrier:
21.System.out.print(”harrier “);
22. }
23. }
24. }
‘What is the result?
A.harrier
B.shepherd
C.retriever
D.Compilation fails.
E.retriever harrier
F. Anexception is thrown at runtime.
Answer:D
Question 53
Given:
12.public class Test {
13.public enum Dogs {collie, harrier};
14.public static void main(String [] args) {
15.Dogs myDog = Dogs.collie;
16.switch (myDog) {
17.case collie:
18.System.out.print(”collie “);
19.case harrier:
20.System.out.print(”harrier “);
21. }
22. }
23. }
Whatis the result?
A.collie
B.harrier
C.Compilation fails.
D.collie harrier
E. Anexception is thrown at runtime.
Answer:D
Question 54
Given:
11.public void testIfA() {
12.if(testIfB(”True”)) {
13.System.out.println(”True”);
14. }else {
15.System.out.println(”Not true”);
16. }
17. }
18.public Boolean testIfB(String str) {
19.return Boolean.valueOf(str);
20. }
Whatis the result when method testIfA is invoked?
A.True
B. Nottrue
C. Anexception is thrown at runtime.
D.Compilation fails because of an error at line 12.
E.Compilation fails because of an error at line 19.
Answer:A
Question 55
Given:
11.public static void main(String[] args) {
12.Integer i = uew Integer(1) + new Integer(2);
13.switch(i) {
14.case 3: System.out.println(”three”); break;
15.default: System.out.println(”other”); break;
16. }
17. }
‘What is the result?
A.three
B.other
C. Anexception is thrown at runtime.
D.Compilation fails because of an error on line 12.
E.Compilation fails because of an error on line 13.
F.Compilation fails because of an error on line 15.
Answer:A
Question 56
Given:
11.public static void main(String[] args) {
12.String str = “null’;
13. if(str == null) {
14. System.out.println(”null”);
15. }else (str.length() == 0) {
16.System.out.println(”zero”);
17. }else {
18.System.out.println(”some”);
19. }
20. }
‘What is the result?
A. null
B. zero
C. some
D.Compilation fails.
E. Anexception is thrown at runtime.
Answer:D
Question 57
Given:
11.Float pi = new Float(3.14f);
12.if(pi>3){
13.System.out.print(”pi is bigger than 3. “);
14. }
15.else {
16.System.out.print(”pi is not bigger than 3. “);
17. }
18.finally {
19.System.out.println(”Have a nice day.”);
20. }
‘What is the result?
A.Compilation fails.
B. piis bigger than 3.
C. Anexception occurs at runtime.
D. piis bigger than 3. Have a nice day.
E. piis not bigger than 3. Have a nice day.
Answer:A
Question 58
Given:
10.intx=0;
11.inty 10;
12. do{
l3.y--;
14.++x;
15. }while (x < 5);
16.System.out.print(x + “,“ + y);
What isthe result?
A. 5,6
B. 5,5
C. 6,5
D. 6,6
Answer:B
Question 59
Given:
25.intx=12;
26.while (x < 10) {
27.x--;
28. }
29.System.out.print(x);
Whatis the result?
A. 0
B. 10
C. 12
D.Line 29 will never be reached.
Answer:C
Question 60
Given:
35.int x= 10;
36. do{
37.x--;
38. }while(x< 10);
Howmany times will line 37 be executed?
A. ten times
B. zero times
C. oneto me times
D.more than ten times
Answer:D
Question 61
Give:
11.public static Iterator reverse(List list) {
12.Collections.reverse(list);
13.return list.iterator();
14. }
15.public static void main(String[] args) {
16.List list = new ArrayList();
17.list.add(” 1”);list.add(”2”);list.add(”3”);
18.for (Object obj: reverse(list))
19.System.out.print(obj + “,”);
20. }
‘What is the result?
A.3,2, 1,
B. 1,2, 3,
C.Compilation fails.
D. Thecode runs with no output.
E. Anexception is thrown at runtime.
Answer:C
Question 62
Given:
11.public static Collection get() {
12.Collection sorted = new LinkedList();
13.sorted.add(’B”); sorted.add(”C”); sorted.add(”A”);
14.return sorted;
15. }
16.public static void main(String[] args) {
17.for (Object obj: get()) {
18.System.out.print(obj + “, “);
19. }
20. }
Whatis the result?
A. A,B, C,
B. B,C, A,
C.Compilation fails.
D. Thecode runs with no output.
E. Anexception is thrown at runtime.
Answer:B
Question 63
Given:
11.public static void main(String[] args) {
12.for (int i=0;i<= 10;i++){
13.if( i>6) break;
14. }
15.System.out.println(i);
16. }
Whatis the result?
A. 6
B. 7
C. 10
D. 11
E.Compilation fails.
F. Anexception is thrown at runtime.
Answer:E
Question 64
Given:
8.public class test {
9.public static void main(String [] a) {
10.assert a.length == 1;
11. }
12. }
Whichtwo will produce an AssertionError? (Choose two.)
A. javatest
B.java -ea test
C.java test file1
D.java -ea test file1
E.java -ea test file1 file2
F.java -ea:test test file1
Answer:BE
Question 65
Given:
12.public class AssertStuff {
13.
14.public static void main(String [] args) {
15.int x= 5;
16. inty= 7;
17.
18.assert (x> y): “stuff”;
19.System.out.println(”passed”);
20. }
21. }
Andthese command line invocations:
javaAssertStuff
java-ea AssertStuff
Whatis the result?
A.passed
stuff
B.stuff
passed
C.passed
AnAssertionError is thrown with the word “stuff” added to the stack
trace.
D.passed
AnAssertionError is thrown without the word “stuff” added to the
stacktrace.
E.passed
AnAssertionException is thrown with the word “stuff” added to the
stacktrace.
F.passed
AnAssertionException is thrown without the word “stuff” added to the
stacktrace.
Answer:C
Question 66
Clickthe Exhibit button.
1.public class Test {
2.
3.public static void main(String [] args) {
4.boolean assert = true;
5.if(assert) {
6.System.out.println(”assert is true”);
7. }
8. }
9.
10. }
Given:
javac-source 1.3 Test.java
Whatis the result?
A.Compilation fails.
B.Compilation succeeds with errors.
C.Compilation succeeds with warnings.
D.Compilation succeeds without warnings or errors.
Answer:C
Question 67
Given:
23.intz=5;
24.
25.public void stuff1(int x) {
26.assert (x> 0);
27.switch(x) {
28.case 2: x= 3;
29.default: assert false; } }
30.
31.private void stuff2(int y) { assert (y < 0); }
32.
33.private void stuff3() { assert (stuff4O); }
34.
35.private boolean stuff4() { z = 6; return false; }
Whichis true?
A. Allof the assert statements are used appropriately.
B.Only the assert statement on line 31 is used appropriately.
C. Theassert statements on lines 29 and 31 are used appropriately.
D. Theassert statements on lines 26 and 29 are used appropriately.
E. Theassert statements on lines 29 and 33 are used appropriately.
F. Theassert statements on lines 29, 31, and 33 are used
appropriately.
G. Theassert statements on lines 26, 29, and 31 are used
appropriately.
Answer:C
Question 68
Clickthe Exhibit button.
SomeException:
1.public class SomeException {
2. }
ClassA:
1.public class A {
2.public void doSomething() { }
3. }
ClassB:
1.public class B extends A {
2.public void doSomething() throws SomeException { }
3. }
Whichis true about the two classes?
A.Compilation of both classes will fail.
B.Compilation of both classes will succeed.
C.Compilation of class A will fail. Compilation of class B will succeed.
D.Compilation of class B will fail. Compilation of class A will succeed.
Answer:D
Question 69
Clickthe Exhibit button.
ClassTestException
1.public class TestException extends Exception {
2. }
ClassA:
1.public class A {
2.
3.public String sayHello(String name) throws TestException {
4.
5.if(name == null) {
6.throw new TestException();
7. }
8.
9.return “Hello “+ name;
10. }
11.
12. }
Aprogrammer wants to use this code in an application:
45. Aa=new A();
46.System.out.println(a.sayHello(”John”));
Whichtwo are true? (Choose two.)
A.Class A will not compile.
B.Line 46 can throw the unchecked exception TestException.
C.Line 45 can throw the unchecked exception TestException.
D.Line 46 will compile if the enclosing method throws a TestException.
E.Line 46 will compile if enclosed in a try block, where TestException
iscaught.
Answer:DE
Question 70
Given:
33.try {
34. //some code here
35. }catch (NullPointerException e1) {
36.System.out.print(”a”);
37. }catch (RuntimeException e2) {
38.System.out.print(”b”);
39. }finally {
40.System.out.print(”c”);
41. }
Whatis the result if a NullPointerException occurs on line 34?
A. c
B. a
C. ab
D. ac
E. bc
F. abc
Answer:D
Question 71
Given:
11.classA{
12.public void process() { System.out.print(”A,”); } }
13.class B extends A {
14. publicvoid process() throws IOException {
15.super.process();
16.System.out.print(”B,”);
17.throw new IOException();
18. }}
19.public static void main(String[] args) {
20.try { new B().process(); }
21.catch (IOException e) { System.out.println(”Exception”); } }
Whatis the result?
A.Exception
B.A,B,Exception
C.Compilation fails because of an error in line 20.
D.Compilation fails because of an error in line 14.
E. ANullPointerException is thrown at runtime.
Answer:D
Question 72
Given:
11.classA{
12.public void process() { System.out.print(”A “); } }
13.class B extends A {
14.public void process() throws RuntimeException {
15.super.process();
16. if(true) throw new RuntimeException();
17.System.out.print(“B”); }}
18.public static void main(String[] args) {
19.try { ((A)new B()).process(); }
20.catch (Exception e) { System.out.print(”Exception “); }
21. }
Whatis the result?
A.Exception
B. AException
C. AException B
D. A BException
E.Compilation fails because of an error in line 14.
F.Compilation fails because of an error in line 19.
Answer:B
Question 73
Given:
11.static classA {
12.void process() throws Exception { throw new Exception(); }
13. }
14.static class B extends A {
15.void process() { System.out.println(”B “); }
16. }
17.public static void main(String[] args) {
18.Aa=new B();
19.a.process();
20.}
Whatis the result?
A. B
B. Thecode runs with no output.
C. Anexception is thrown at runtime.
D.Compilation fails because of an error in line 15.
E.Compilation fails because of an error in line 18.
F.Compilation fails because of an error in line 19.
Answer:F
Question 74
Given:
11.static class A {
12.void process() throws Exception { throw new Exception(); }
13. }
14.static class B extends A {
15.void process() { System.out.println(”B”); }
16. }
17.public static void main(String[] args) {
18.new B().process();
19. }
Whatis the result?
A. B
B. Thecode runs with no output.
C.Compilation fails because of an error in line 12.
D.Compilation fails because of an error in line 15.
E.Compilation fails because of an error in line 18.
Answer:A
Question 75
Given:
84.try {
85.ResourceConnection con = resourceFactory.getConnection();
86.Results r = con.query(”GET INFO FROM CUSTOMER”);
87. info = r.getData();
88. con.close();
89. }catch (ResourceException re) {
90.errorLog.write(re.getMessage());
91. }
92.return info;
Whichis true if a ResourceException is thrown on line 86?
A.Line 92 will not execute.
B. Theconnection will not be retrieved in line 85.
C. Theresource connection will not be closed on line 88.
D. Theenclosing method will throw an exception to its caller.
Answer:C
Question 76
Clickthe Exhibit button.
1.public class A {
2.public void method1() {
3. Bb=new B();
4.b.method2();
5. //more code here
6. }
7. }
1.public class B {
2.public void method2() {
3.Cc=new C();
4.c.method3();
5. //more code here
6. }
7. }
1.public class C {
2.public void method3() {
3. //more code here
4. }
5. }
Given:
25.try {
26. Aa=new A();
27.a.method1();
28. }catch (Exception e) {
29.System.out.print(”an error occurred”);
30. }
Whichtwo are true if a NullPointerException is thrown on line 3 of
classC? (Choose two.)
A. Theapplication will crash.
B. Thecode on line 29 will be executed.
C. Thecode on line 5 of class A will execute.
D. Thecode on line 5 of class B will execute.
E. Theexception will be propagated back to line 27.
Answer:BE
Question 77
Clickthe Exhibit button.
1.public class A {
2.public void method1() {
3. try{
4. Bb=new B();
5.b.method2();
6. //more code here
7. }catch (TestException te) {
8.throw new RuntimeException(te);
9. }
6. }
7. }
1.public class B {
2.public void method2() throws TestException {
3. //more code here
4. }
5. }
1.public class TestException extends Exception {
2. }
Given:
31.public void method() {
32. Aa=new A();
33.a.method1();
34. }
Whichis true if a TestException is thrown on line 3 of class B?
A.Line 33 must be called within a try block.
B. Theexception thrown by method1 inclass A is not required to be
caught.
C. Themethod declared on line 31 must be declared to throw a
RuntimeException.
D. Online 5 of class A, the call to method2 of class B does not need to
beplaced in a try/catch block.
Answer:B
Question 78
Given:
11.public static void main(String[] args) {
12.try {
13.args=null;
14.args[0] = “test”;
15.System.out.println(args[0]);
16. }catch (Exception ex) {
17.System.out.println(”Exception”);
18. }catch (NullPointerException npe) {
19.System.out.println(”NullPointerException”);
20. }
21. }
Whatis the result?
A.test
B.Exception
C.Compilation fails.
D.NullPointerException
Answer:C
Question 79
Given:
11.static void test() throws Error {
12. if(true) throw new AssertionError();
13.System.out.print(”test “);
14. }
15.public static void main(String[] args) {
16.try { test(); }
17.catch (Exception ex) { System.out.print(”exception “); }
18.System.out.print(”elld “);
19. }
Whatis the result?
A. end
B.Compilation fails.
C.exception end
D.exception test end
E. AThrowable is thrown by main.
F. AnException is thrown by main.
Answer:E
Question 80
Given:
11.static void test() {
12.try {
13.String x=null;
14.System.out.print(x.toString() +“ “);
15. }
16.finally { System.out.print(“finally “); }
17. }
18.public static void main(String[] args) {
19.try { test(); }
20.catch (Exception ex) { System.out.print(”exception “); }
21. }
Whatis the result?
A.null
B.finally
C.null finally
D.Compilation fails.
E.finally exception
Answer:E
Question 81
Given:
11.static void test() throws RuntimeException {
12.try {
13.System.out.print(”test “);
14.throw new RuntimeException();
15. }
16.catch (Exception ex) { System.out.print(”exception “); }
17. }
18.public static void main(String[] args) {
19.try { test(); }
20.catch (RuntimeException ex) { System.out.print(”runtime “); }
21.System.out.print(”end “);
22. }
Whatis the result?
A.test end
B.Compilation fails.
C.test runtime end
D.test exception end
E. AThrowable is thrown by main at runtime.
Answer:D
Question 82
Givena method that must ensue that its parameter is not null:
11.public void someMethod(Object value) {
12. //check for null value
....
20.System.out.println(value.getClass());
21. }
What,inserted at line 12, is the appropriate way to handle a null
value?
A.assert value == null;
B.assert value !null, “value is null”;
C. if(value == null) {
thrownew AssertionException(”value is null”);
D. if(value == null) {
thrownew IllegalArgumentException(”value is null”);
Answer:D
Question 83
Clickthe Exhibit button.
10.public class ClassA {
11.public void methodA() {
12.ClassB classB = new ClassB();
13.classB.getValue();
14. }
15. }
And:
20.class ClassB {
21.public ClassC classC;
22.
23.public String getValue() {
24.return classC.getValue();
25. }
26. }
And:
30.class ClassC {
31.public String value;
32.
33.public String getValue() {
34.value = “ClassB”;
35.return value;
36. }
37. }
Given:
ClassAa = new ClassA();
a.methodA();
Whatis the result?
A.Compilation fails.
B.ClassC is displayed.
C. Thecode runs with no output.
D. Anexception is thrown at runtime.
Answer:D
Question 84
Given:
10.public class Foo {
11.static int[] a;
12.static { a[0]=2; }
13.public static void main( String[] args) {}
14. }
Whichexception or error will be thrown when a programmer attempts
to runthis code?
A.java.lang. StackOverflowError
B.java.lang.IllegalStateException
C.java.lang.ExceptionlnlnitializerError
D.java.lang.ArraylndexOutOfBoundsException
Answer:C
Question 85
Given:
10.public class ClassA {
11.public void count(int i) {
12.count(++i);
13. }
14. }
And:
20.ClassA a = new ClassA();
21.a.count(3);
Whichexception or error should be thrown by the virtual machine?
A.StackOverflowError
B.NullPointerException
C.NumberFormatException
D.IllegalArgumentException
E.ExceptionlnlnitializerError
Answer:A
Question 86
Given:
1.public class Boxer1 {
2.Integer i;
3. intx;
4.public Boxer1(int y) {
5.x=i+y;
6.System.out.println(x);
7. }
8.public static void main(String[] args) {
9. newBoxer1(new Integer(4));
10. }
11. }
Whatis the result?
A. Thevalue “4” is printedat the command line.
B.Compilation fails because of an error in line 5.
C.Compilation fails because of an error in line 9.
D. ANullPointerException occurs at runtime.
E. ANumberFormatException occurs at runtime.
F. AnIllegalStateException occurs at runtime.
Answer:D
Question 87
Given:
1.public class TestString 1 {
2.public static void main(String[] args) {
3.String str = “420”;
4. str+= 42;
5.System.out.print(str);
6. }
7. }
Whatis the output?
A. 42
B. 420
C. 462
D.42042
E.Compilation fails.
F. Anexception is thrown at runtime.
Answer:D
Question 88
Given:
11.class Converter {
12.public static void main(String[] args) {
13.Integer i = args[0];
14.int j = 12;
15.System.out.println(”It is “ + (j==i) + “that j==i.”);
16. }
17. }
Whatis the result when the programmer attempts to compile the code
andrun it with the command java Converter 12?
A. Itis true that j==i.
B. Itis false that j==i.
C. Anexception is thrown at runtime.
D.Compilation fails because of an error in line 13.
Answer:D
Question 89
Giventhis method in a class:
21.public String toString() {
22.StringBuffer buffer = new StringBuffer();
23.buffer.append(’<’);
24.buffer.append(this.name);
25.buffer.append(’>’);
26. returnbuffer.toString();
27. }
Whichis true?
A.This code is NOT thread-safe.
B. Theprogrammer can replace StringBuffer with StringBuilder with no
otherchanges.
C.This code will perform well and converting the code to use
StringBuilderwill not enhance the performance.
D.This code will perform poorly. For better performance, the code
shouldbe rewritten: return “<“+ this.name + “>”;
Answer:B
Question 90
Given:
1.public class MyLogger {
2.private StringBuilder logger = new StringBuuilder();
3.public void log(String message, String user) {
4.logger.append(message);
5.logger.append(user);
6. }
7. }
Theprogrammer must guarantee that a single MyLogger object works
properlyfor a multi-threaded system. How must this code be changed
to bethread-safe?
A.synchronize the log method
B.replace StringBuilder with StringBuffer
C. Nochange is necessary, the current MyLogger code is already
thread-safe.
D.replace StringBuilder with just a String object and use the string
concatenation(+=) within the log method
Answer:A
Question 91
Given:
11.public String makinStrings() {
12.String s = “Fred”;
13. s= s + “47”;
14. s= s.substring(2, 5);
15. s= s.toUpperCase();
16.return s.toString();
17. }
Howmany String objects will be created when this method is invoked?
A. 1
B. 2
C. 3
D. 4
E. 5
F. 6
Answer:C
Question 92
Given:
1.public class TestString3 {
2.public static void main(String[] args) {
3. //insert code here
5.System.out.println(s);
6. }
7. }
Whichtwo code fragments, inserted independently at line 3, generate
theoutput 4247? (Choose two.)
A.String s = “123456789”;
s =(s-”123”).replace(1,3,”24”) - “89”;
B.StringBuffer s = new StringBuffer(”123456789”);
s.delete(0,3).replace(1,3, “24”).delete(4,6);
C.StringBuffer s = new StringBuffer(”123456789”);
s.substring(3,6).delete(1 ,3).insert( 1, “24”);
D.StringBuilder s = new StringBuilder(”123456789”);
s.substring(3,6).delete(1 ,2).insert( 1, “24”);
E.StringBuilder s = new StringBuilder(”123456789”);
s.delete(0,3).delete( 1 ,3).delete(2,5).insert( 1, “24”);
Answer:BE
Question 93
Given:
11.public class Yikes {
12.
13.public static void go(Long n) {System.out.println(”Long “);}
14.public static void go(Short n) {System.out.println(”Short “);}
15.public static void go(int n) {System.out.println(”int “);}
16.public static void main(String [] args) {
17.short y= 6;
18.long z= 7;
19.go(y);
20.go(z);
21. }
22. }
Whatis the result?
A. intLong
B.Short Long
C.Compilation fails.
D. Anexception is thrown at runtime.
Answer:A
Question 94
Given:
12. publicclass Wow {
13.public static void go(short n) {System.out.println(”short”); }
14.public static void go(Short n) {System.out.println(”SHORT”);}
15.public static void go(Long n) {System.out.println(” LONG”); }
16.public static void main(String [] args) {
17.Short y= 6;
18.intz=7;
19.go(y);
20.go(z);
21. }
22. }
Whatis the result?
A.short LONG
B.SHORT LONG
C.Compilation fails.
D. Anexception is thrown at runtime.
Answer:C
Question 95
Given:
10.class MakeFile {
11.public static void main(String[] args) {
12.try {
13.File directory = new File(”d”);
14.File file = new File(directory,”f”);
15.if(!file.exists()) {
16.file.createNewFile();
17. }
18. }catch (IOException e) {
19.e.printStackTrace
20. }
21. }
22. }
Thecurrent directory does NOT contain a directory named “d.”
Whichthree are true? (Choose three.)
A.Line 16 is never executed.
B. Anexception is thrown at runtime.
C.Line 13 creates a File object named “d.”
D.Line 14 creates a File object named “f.’
E.Line 13 creates a directory named “d” in the file system.
F.Line 16 creates a directory named “d” and a file ‘f’ within it in the
filesystem.
G.Line 14 creates a file named ‘f’ inside of the directory named “d” in
thefile system.
Answer:BCD
Question 96
Whencomparing java.io.BufferedWriter to java.io.FileWriter, which
capabilityexists as a method in only one of the two?
A.closing the stream
B.flushing the stream
C.writing to the stream
D.marking a location in the stream
E.writing a line separator to the stream
Answer:E
Question 97
Given:
12.import java.io.*;
13.public class Forest implements Serializable {
14.private Tree tree = new Tree();
15.public static void main(String [] args) {
16.Forest f= new Forest();
17.try {
18.FileOutputStream fs = new FileOutputStream(”Forest.ser”);
19.ObjectOutputStream os = new ObjectOutputStream(fs);
20.os.writeObject(f); os.close();
21. }catch (Exception ex) { ex.printStackTrace(); }
22. }}
23.
24.class Tree { }
Whatis the result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C. Aninstance of Forest is serialized.
D. Ainstance of Forest and an instance of Tree are both serialized.
Answer:B
Question 98
Clickthe Exhibit button.
1.import java.io.*;
2.public class Foo implements Serializable {
3.public int x, y;
4.public Foo( int x, int y) { this.x = x; this.y = y; }
5.
6.private void writeObject( ObjectOutputStream s)
7.throws IOException {
8.s.writeInt(x); s.writeInt(y)
9. }
10.
11.private void readObject( ObjectInputStream s)
12.throws IOException, ClassNotFoundException {
13.
14. //insert code here
15.
16. }
17. }
Whichcode, inserted at line 14, will allow this class to correctly
serializeand deserialize?
A.s.defaultReadObject();
B.this = s.defaultReadObject();
C. y =s.readInt(); x = s.readInt();
D. x =s.readInt(); y = s.readInt();
Answer:D
Question 99
Whichthree concerning the use of the java.io.Serializable interface are
true?(Choose three.)
A.Objects from classes that use aggregation cannot be serialized.
B. Artobject serialized on one JVM can be successfully deserialized on
adifferent JVM.
C. Thevalues in fields with the volatile modifier will NOT survive
serializationand deserialization.
D. Thevalues in fields with the transient modifier will NOT survive
serializationand deserialization.
E. Itis legal to serialize an object of a type that has a supertype that
doesNOT implement java.io.Serializable.
Answer:BDE
Question 100
Assumingthat the serializeBanana() and the deserializeBanana()
methodswill correctly use Java serialization and given:
13.import java.io.*;
14.class Food implemertts Serializable {int good = 3;}
15.class Fruit externds Food {int juice = 5;}
16.public class Banana extends Fruit {
17.int yellow = 4;
18.public static void main(String [] args) {
19. Banana b = new Banana(); Banana b2 = new Banana();
20. b.serializeBanana(b); // assume correctserialization
21. b2 = b.deserializeBanana(); // assume correct
22.System.out.println(”restore “+b2.yellow+ b2.juice+b2.good);
24. }
25. //more Banana methods go here
50. }
‘What is the result?
A.restore 400
B.restore 403
C.restore 453
D.Compilation fails.
E. Anexception is thrown at runtime.
Answer:C
Question 101
Assumingthat the serializeBanana2() and the deserializeBanana2()
methodswill correctly use Java serialization and given:
13.import java.io.*;
14.class Food {Food() { System.out.print(”1”); } }
15.class Fruit extends Food implements Serializable {
16.Fruit() { System.out.print(”2”);} }
17.public class Banana2 extends Fruit { int size = 42;
18. publicstatic void main(String [] args) {
19. Banana2 b = new Banana2();
20. b.serializeBanana2(b); // assume correctserialization
21. b = b.deserializeBanana2(b); // assume correct
22.System.out.println(” restored “+ b.size + “ “); }
23. //more Banana2 methods
24. }
Whatis the result?
A.Compilation fails.
B. 1restored 42
C. 12restored 42
D. 121restored 42
E.1212 restored 42
F. Anexception is thrown at runtime.
Answer:D
Question 102
Given:
10.public class Foo implements java.io.Serializable {
11. privateint x;
12.public int getX() { return x; }
12.publicFoo(intx){this.x=x; }
13.private void writeObject( ObjectOutputStream s)
14.throws IOException {
15. //insert code here
16. }
17. }
Whichcode fragment, inserted at line 15, will allow Foo objects to be
correctlyserialized and deserialized?
A.s.writeInt(x);
B.s.serialize(x);
C.s.writeObject(x);
D.s.defaultWriteObject();
Answer:D
Question 103
Given:
12.NumberFormat nf= NumberFormat.getInstance();
13.nf.setMaximumFractionDigits(4);
14. nf.setMinimumFractionDigits(2);
15.String a = nf.format(3.1415926);
16.String b = nf.format(2);
Whichtwo are true about the result if the default locale is Locale.US?
(Choosetwo.)
A. Thevalue of b is 2.
B. Thevalue of a is 3.14.
C. Thevalue of b is 2.00.
D. Thevalue of a is 3.141.
E. Thevalue of a is 3.1415.
F. Thevalue of a is 3.1416.
G. Thevalue of b is 2.0000.
Answer:CF
Question 104
Given:
11.double input = 314159.26;
12.NumberFormat nf= NumberFormat.getInstance(Locale.ITALIAN);
13.String b;
14.//insert code here
Whichcode, inserted at line 14, sets the value of b to 3 14.159,26?
A. b =nf.parse( input);
B. b = nf.format( input);
C. b =nf.equals( input);
D. b =nf.parseObject( input);
Answer:B
Question 105
Given:
14.DateFormat df;
15. Datedate = new Date();
16.//insert code here
17.String s = df.format( date);
Whichtwo, inserted independently at line 16, allow the code to
compile?(Choose two.)
A. df=new DateFormat();
B. df= Date.getFormatter();
C. df= date.getFormatter();
D. df= date.getDateFormatter();
E. df= Date.getDateFormatter();
F. df= DateFormat.getInstance();
G. df = DateFormat.getDateInstance();
Answer: FG
Question 106
Given:
12.Date date = new Date();
13.df.setLocale(Locale.ITALY);
14.String s = df.format(date);
Thevariable df is an object of type DateFormat that has been
initializedin line 11. What is the result if this code is run on December
14,2000?
A. Thevalue of s is 14-dic-2004.
B. Thevalue of s is Dec 14, 2000.
C. Anexception is thrown at runtime.
D.Compilation fails because of an error in line 13.
Answer:D
Question 107
Given:
33.Date d = new Date(0);
34.String ds = “December 15, 2004”;
35. //insert code here
36.try {
37. d= df.parse(ds);
38. }
39.catch(ParseException e) {
40.System.out.println(”Unable to parse “+ ds);
41. }
42. //insert code here too
Whichwill create the appropriate DateFormat object and add a day to
theDate object?
A. 35.DateFormat df= DateFormat.getDateFormat();
42.d.setTime( (60 * 60 * 24) + d.getTime());
B. 35.DateFormat df= DateFormat.getDateJnstance();
42.d.setTime( (1000 * 60 * 60 * 24) + d.getTime());
C. 35. DateFormat df= DateFormat.getDateFormat();
42.d.setLocalTime( (1000*60*60*24) + d.getLocalTime());
D. 35.DateFormat df= DateFormat.getDateJnstance();
42.d.setLocalTime( (60 * 60 * 24) + d.getLocalTime());
Answer:B
Question 108
Givena valid DateFormat object named df, and
16.Date d = new Date(0L);
17.String ds = “December 15, 2004”;
18. //insert code here
Whatupdates d’s value with the date represented by ds?
A. 18.d = df.parse(ds);
B. 18.d = df.getDate(ds);
C. 18.try {
19. d= df.parse(ds);
20. }catch(ParseException e) { };
D. 18.try {
19. d= df.getDate(ds);
20. }catch(ParseException e) { };
Answer:C
Question 109
Given:
11.String test = “This is a test”;
12.String[] tokens = test.split(”\s”);
13.System.out.println(tokens.length);
Whatis the result?
A. 0
B. 1
C. 4
D.Compilation fails.
E. Anexception is thrown at runtime.
Answer:D
Question 110
Given:
11.String test= “a1b2c3”;
12.String[] tokens = test.split(”\\d”);
13.for(String s: tokens) System.out.print(s +“ “);
Whatis the result?
A. a bc
B. 1 23
C. a1b2c3
D. a1b2 c3
E.Compilation fails.
F. Thecode runs with no output.
G. Anexception is thrown at runtime.
Answer:A
Question 111
Given:
11.String test = “Test A. Test B. Test C.”;
12. //insert code here
13.String[] result = test.split(regex);
Whichregular expression inserted at line 12 will correctly split test into
“Test A,” “Test B,” and “TestC”?
A.String regex = “”;
B.String regex = “ “;
C.String regex = “.*“.
D.String regex = “\\s”
E.String regex = “\\.\\s*”;
F.String regex = “\\w[ \.] +“;
Answer:E
Question 112
Given:
12.System.out.format(”Pi is approximately %d.”, Math.PI);
Whatis the result?
A.Compilation fails.
B. Piis approximately 3.
C. Piis approximately 3.141593.
D. Anexception is thrown at runtime.
Answer:D
Question 113
Given:
12.String csv = “Sue,5,true,3”;
13.Scanner scanner = new Scanner( csv);
14.scanner.useDelimiter(”,”);
15.int age = scanner.nextInt();
Whatis the result?
A.Compilation fails.
B.After line 15, the value of age is 5.
C.After line 15, the value of age is 3.
D. Anexception is thrown at runtime.
Answer:D
Question 114
Whichtwo code fragments will execute the method doStuff() in a
separatethread? (Choose two.)
A. newThread() {
publicvoid run() { doStuff(); }
}
B. newThread() {
publicvoid start() { doStuff(); }
}
C. newThread() {
publicvoid start() { doStuff(); }
}.run();
D. newThread() {
publicvoid run() { doStuff(); }
}.start();
E. newThread(new Runnable() {
publicvoid run() { doStuff(); }
}).run();
F. newThread(new Runnable() {
publicvoid run() { doStuff(); }
}).start();
Answer:DF
Question 115
Given:
1.public class Threads3 implements Runnable {
2.public void run() {
3.System.out.print(”running”);
4. }
5.public static void main(String[] args) {
6.Thread t = new Thread(new Threads3());
7.t.run();
8.t.run();
9.t.start();
10. }
11. }
Whatis the result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C. Thecode executes and prints “running”.
D. Thecode executes and prints “runningrunning”.
E. Thecode executes and prints “runningrunningrunning”.
Answer:E
Question 116
Given:
1.public class Threads4 {
2.public static void main (String[] args) {
3. newThreads4().go();
4. }
5.public void go() {
6.Runnable r = new Runnable() {
7.public void run() {
8.System.out.print(”foo”);
9. }
10. };
11.Thread t = new Thread(r);
12.t.start();
13.t.start();
14. }
15. }
Whatis the result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C. Thecode executes normally and prints ‘foo”.
D. Thecode executes normally, but nothing is printed.
Answer:B
Question 117
Given:
1.public class Threads5 {
2.public static void main (String[] args) {
3. newThread(new Runnable() {
4.public void run() {
5.System.out.print(”bar”);
6.}}).start();
7. }
8. }
Whatis the result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C. Thecode executes normally and prints “bar”.
D. Thecode executes normally, but nothing prints.
Answer:C
Question 118
Given:
11.Runnable r = new Runnable() {
12.public void run() {
13.System.out.print(”Cat”);
14. }
15. };
16.Threadt=new Thread(r) {
17.public void run() {
18.System.out.print(”Dog”);
19. }
20. };
21.t.start();
Whatis the result?
A. Cat
B. Dog
C.Compilation fails.
D. Thecode runs with no output.
E. Anexception is thrown at runtime.
Answer:B
Question 119
Clickthe Exhibit button.
Given:
10.public class Starter extends Thread {
11.private int x= 2;
12.public static void main(String[] args) throws Exception {
13.new Starter().makeItSo();
14. }
15.public Starter() {
16.x=5;
17.start();
18. }
19.public void makeItSo() throws Exception {
20.join();
21.x=x- 1;
22.System.out.println(x);
23. }
24.public void run() { x *= 2; }
25. }
Whatis the output if the main() method is rum?
A. 4
B. 5
C. 8
D. 9
E.Compilation fails.
F. Anexception is thrown at runtime.
G. Itis impossible to determine for certain.
Answer:D
Question 120
Given:
1.public class Threads2 implements Runnable {
2.
3.public void nun() {
4.System.out.println(”run.”);
5.throw new RuntimeException(”Problem”);
6. }
7.public static void main(String[] args) {
8.Thread t = new Thread(new Threads2());
9.t.start();
10.System.out.println(”End of method.”);
11. }
12. }
Whichtwo can be results? (Choose two.)
A.java.lang.RuntimeException: Problem
B.run.
java.lang.RuntimeException:Problem
C. Endof method.
java.lang.RuntimeException:Problem
D. Endof method.
run.
java.lang.RuntimeException:Problem
E.run.
java.lang.RuntimeException:Problem
End ofmethod.
Answer:DE
Question 121
Given:
1.public class TestOne {
2.public static void main (String[] args) throws Exception {
3.Thread.sleep(3000);
4.System.out.println(”sleep”);
5. }
6. }
Whatis the result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C. Thecode executes normally and prints “sleep”.
D. Thecode executes normally, but nothing is printed.
Answer:C
Question 122
Given:
1.public class TestOne implements Runnable {
2. publicstatic void main (String[] args) throws Exception {
3.Thread t = new Thread(new TestOne());
4.t.start();
5.System.out.print(”Started”);
6.t.join();
7.System.out.print(”Complete”);
8. }
9.public void run() {
10.for (int i= 0; i< 4; i++) {
11. System.out.print(i);
12. }
13. }
14. }
Whatcan be a result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C. Thecode executes and prints “StartedComplete”.
D. Thecode executes and prints “StartedComplete0123”.
E. Thecode executes and prints “Started0l23Complete”.
Answer:E
Question 123
Clickthe Exhibit button.
Given:
1.public class TwoThreads {
2
3.private static Object resource = new Object();
4.
5.private static void delay(long n) {
6. try{ Thread.sleep(n); }
7.catch (Exception e) { System.out.print(”Error “); }
8. }
9
10.public static void main(String[] args) {
11.System.out.print(”StartMain “);
12.new Thread1().start();
13.delay(1000);
14.Thread t2 = new Thread2();
15.t2.start();
16.delay(1000);
17.t2.interrupt
18.delay(1000);
19.System.out.print(”EndMain “);
20. }
21.
22.static class Thread 1 extends Thread {
23.public void run() {
24.synchronized (resource) {
25.System.out.print(”Startl “);
26.delay(6000);
27.System.out.print(”End1 “);
28. }
29. }
30. }
31.
32.static class Thread2 extends Thread {
33.public void run() {
34.synchronized (resource) {
35.System.out.print(”Start2 “);
36.delay(2000);
37.System.out.print(”End2 “);
38. }
39. }
40. }
41. }
Assumethat sleep(n) executes in exactly m milliseconds, and all other
codeexecutes in an insignificant amount of time. What is the output if
themain() method is run?
A.Compilation fails.
B.Deadlock occurs.
C.StartMain Start1 Error EndMain End1
D.StartMain Start1 EndMain End1 Start2 End2
E.StartMain Start1 Error Start2 EndMain End2 End1
F.StartMain Start1 Start2 Error End2 EndMain End1
G.StartMain Start1 EndMain End1 Start2 Error End2
Answer:G
Question 125
Given:
publicclass NamedCounter {
privatefinal String name;
privateint count;
publicNamedCounter(String name) { this.name = name; }
publicString getName() { return name; }
publicvoid increment() { coount++; }
publicint getCount() { return count; }
publicvoid reset() { count = 0; }
}
Whichthree changes should be made to adapt this class to be used
safelyby multiple threads? (Choose three.)
A.declare reset() using the synchronized keyword
B.declare getName() using the synchronized keyword
C.declare getCount() using the synchronized keyword
D.declare the constructor using the synchronized keyword
E.declare increment() using the synchronized keyword
Answer:ACE
Question 125
Clickthe Exhibit button:
1.public class Threads 1 {
2.intx=0;
3.public class Runner implements Runnable {
4.public void run() {
5. intcurrent = 0;
6.for(int=i=0;i<4;i++){
7.current = x;
8.System.out.print(current + “, “);
9. x =current + 2;
10. }
11. }
12. }
13.
14.public static void main(String[] args) {
15.new Threads1().go();
16. }
17.
18.public void go() {
19.Runnable r1 = new Runner();
20.new Thread(r1).start();
21.new Thread(r1 ).start();
22. }
23. }
Whichtwo are possible results? (Choose two.)
A. 0,2, 4, 4, 6, 8, 10, 6,
B. 0,2, 4, 6, 8, 10, 2, 4,
C. 0,2, 4, 6, 8, 10, 12, 14,
D. 0,0, 2, 2, 4, 4, 6, 6, 8, 8, 10, 10, 12, 12, 14, 14,
E. 0,2, 4, 6, 8, 10, 12, 14, 0, 2, 4, 6, 8, 10, 12, 14,
Answer:AC
Question 126
Clickthe Exhibit button.
1.import java.util.*;
2.
3.public class NameList {
4.private List names = new ArrayList();
5.public synchronized void add(String name) { names.add(name); }
6.public synchronized void printAll() {
7. for(int i = 0; i <names.size(); i++) {
8.System.out.print(names.get(i) +“ “);
9. }
10. }
11.public static void main(String[] args) {
12.final NameList sl = new NameList();
13.for(inti=0;i<2;i++) {
14.new Thread() {
15. publicvoid ruin() {
16.sl.add(”A”);
17.sl.add(”B”);
18.sl.add(”C”);
19.sl.printAll();
20. }
21.}.start();
22. }
23. }
24. }
Whichtwo statements are true if this class is compiled and run?
(Choosetwo.)
A. Anexception may be thrown at runtime.
B. Thecode may run with no output, without exiting.
C. Thecode may run with no output, exiting normally.
D. Thecode may rum with output “A B A B C C “, then exit.
E. Thecode may rum with output “A B C A B C A B C “, then exit.
F. Thecode may ruin with output “A A A B C A B C C “, then exit.
G. Thecode may ruin with output “A B C A A B C A B C “, then exit.
Answer:EG
Question 127
Given:
1.public class TestFive {
2.private int x;
3.public void foo() {
4 intcurrent = x;
5. x =current + 1;
6. }
7.public void go() {
8.for(int i=0;i<5;i++) {
9. newThread() {
10.public void run() {
11.foo();
12.System.out.print(x + “, “);
13. }}.start();
14.}}}
Whichtwo changes, taken together, would guarantee the output: 1, 2,
3, 4,5, ? (Choose two.)
A.Move the line 12 print statement into the foo() method.
B.Change line 7 to public synchronized void go() {.
C.Change the variable declaration on line 3 to private volatile int x;.
D.Wrap the code inside the foo() method with a synchronized( this )
block.
E.Wrap the for loop code inside the go() method with a synchronized
blocksynchronized(this) { // for loop code here }.
Answer:AD
Question 128
Whichthree will compile and rim without exception? (Choose three.)
A.private synchronized Object o;
B.void go() {
synchronized(){ /* code here */ }
}
C.public synchronized void go() { /* code here */ }
D.private synchronized(this) void go() { /* code here */ }
E.void go() {
synchronized(Object.class){ /* code here */ }
}
F.void go() {
Objecto = new Object();
synchronized(o){ /* code here */ }
}
Answer:CEF
Question 129
Given:
1.public class TestSeven extends Thread {
2.private static int x;
3.public synchronized void doThings() {
4. intcurrent = x;
5.current++;
6. x =current;
7. }
8.public void run() {
9. doThings();
10. }
1 1.}
Whichis true?
A.Compilation fails.
B. Anexception is thrown at runtime.
C.Synchronizing the run() method would make the class thread-safe.
D. Thedata in variable “x” are protected from concurrent access
problems.
E.Declaring the doThings() method as static would make the class
thread-safe.
F.Wrapping the statements within doThings() in a synchronized(new
Object()){ } block would make the class thread-safe.
Answer:E
Question 130
Clickthe Exhibit button.
10.public class Transfers {
11.public static void main(String[] args) throws Exception {
12.Record r1 = new Record();
13.Record r2 = new Record();
14. doTransfer(r1, r2, 5);
15. doTransfer(r2, r1, 2);
16.doTransfer(r1, r2, 1);
17. //print the result
18.System.out.println(”rl = “ + r1.get() +“, r2=” + r2.get());
19. }
20.private static void doTransfer(
21.final Record a, final Record b, final int amount) {
22.Thread t = new Thread() {
23.public void run() {
24.new Clerk().transfer(a, b, amount);
25. }
26. };
27.t.start();
28. }
29. }
30.class Clerk {
31.public synchronized void transfer(Record a, Record b, int amount){
32.synchronized (a) {
33.synchronized (b) {
34.a.add(-amount);
35.b.add(amount);
36. }
37. }
38. }
39. }
40.class Record {
41.intnum=10;
42. publicint get() { return num; }
43. public void add(int n) { num = num + n; }
44. }
IfTransfers.main() is run, which three are true? (Choose three.)
A. Theoutput may be “r1 = 6, r2 = 14”.
B. Theoutput may be “r1 = 5, r2 = 15”.
C. Theoutput may be “r1 = 8, r2 = 12”.
D. Thecode may run (and complete) with no output.
E. Thecode may deadlock (without completing) with no output.
F. MIllegalStateException or InterruptedException may be thrown at
runtime.
Answer:ABE
Question 131
Clickthe Exhibit button.
1.class Computation extends Thread {
2.
3.private int num;
4.private boolean isComplete;
5.private int result;
6.
7.public Computation(int num) { this.num = num; }
8.
9.public synchronized void run() {
10.result = num * 2;
11.isComplete = true;
12. notify();
13. }
14.
15.public synchronized int getResult() {
16.while (!isComplete) {
17.try {
18.wait();
19. }catch (InterruptedException e) { }
20. }
21.return result;
22. }
23.
24.public static void main(String[] args) {
25.Computation[] computations = new Computation [4];
26.for (int i = 0; i < computations.length; i++) {
27.computations[i] = new Computation(i);
28.computations[i] .start();
29. }
30.for (Computation c : computations)
31.System.out.print(c.getResult() +“ “);
32. }
33. }
Whatis the result?
A. Thecode will deadlock.
B. Thecode may run with no output.
C. Anexception is thrown at runtime.
D. Thecode may run with output “0 6”.
E. Thecode may run with output “2 0 6 4’.
F. Thecode may ruin with output “0 2 4 6”.
Answer:F
Question 132
Given:
7.void waitForSignal() {
8.Object obj = new Object();
9.synchronized (Thread.currentThread()) {
10.obj.wait();
11.obj.notify();;
12. }
13. }
Whichis true?
A.This code may throw an InterruptedException.
B.This code may throw an IllegalStateException.
C.This code may throw a TimeoutException after ten minutes.
D.This code will not compile unless “obj.wait()” is replaced with
“((Thread) obj).wait()”.
E.Reversing the order of obj.wait() and obj.notify() may cause this
methodto complete normally.
F. Acall to notify() or notifyAll() from another thread may cause this
methodto complete normally.
Answer:B
Question 133
Given:
fooand bar are public references available to many other threads. foo
refersto a Thread and bar is an Object. The thread foo is currently
executingbar.wait(). From another thread, which statement is the
mostreliable way to ensue that foo will stop executing wait()?
A.foo.notify();
B.bar.notify();
C.foo.notifyAll();
D.Thread.notify();
E.bar.notiFYAll();
F. Object.notify();
Answer:E
Question 134
Whichtwo are true? (Choose two.)
A. Anencapsulated, public class promotes re-use.
B.Classes that share the same interface are always tightly
encapsulated.
C. Anencapsulated class allows subclasses to overload methods, but
doesNOT allow overriding methods.
D. Anencapsulated class allows a programmer to change an
implementationwithout affecting outside code.
Answer:AD
Question 135
Given:
1.package test;
2.
3.class Target {
4.public String name = “hello”;
5. }
Whatcan directly access and change the value of the variable name?
A. anyclass
B.only the Target class
C. anyclass in the test package
D. anyclass that extends Target
Answer:C
Question 136
Given:
1.public class Target {
2.private int i = 0;
3. publicint addOne() {
4.return ++i;
5. }
6. }
And:
1.public class Client {
2.public static void main(String[] args) {
3.System.out.println(new Target().addOne());
4. }
5. }
Whichchange can you make to Target without affecting Client?
A.Line 4 of class Target can be changed to return i++;
B.Line 2 of class Target can be changed to private int i = 1;
C.Line 3 of class Target can be changed to private int addOne() {
D.Line 2 of class Target can be changed to private Integer i = 0;
Answer:D
Question 137
Given:
1.package geometry;
2.public class Hypotenuse {
3.public InnerTriangle it = new InnerTriangle();
4.class InnerTriangle {
5.public int base;
6.public int height;
7. }
8. }
Whichis true about the class of an object that can reference the
variablebase?
A. Itcan be any class.
B. Noclass has access to base.
C. Theclass must belong to the geometry package.
D. Theclass must be a subclass of the class Hypotenuse.
Answer:C
Question 138
Given:
11.class ClassA {}
12.class ClassB extends ClassA {}
13.class ClassC extends ClassA {}
and:
21.ClassA p0 = new ClassA();
22.ClassB p1 = new ClassB();
23.ClassC p2 = new ClassC();
24.ClassA p3 = new ClassB();
25.ClassA p4 = new ClassC();
Whichthree are valid? (Choose three.)
A. p0= p1;
B. p1=p2;
C. p2= p4;
D. p2= (ClassC)p1;
E. p1= (ClassB)p3;
F. p2= (ClassC)p4;
Answer:AEF
Question 139
Given:
11.class Animal { public String noise() { return “peep”; } }
12.class Dog extends Animal {
13.public String noise() { return “bark”; }
14. }
15.class Cat extends Animal {
16.public String noise() { return “meow”; }
17. }
.....
30.Animal animal = new Dog();
31.Cat cat = (Cat)animal;
32.System.out.printIn(cat.noise());
Whatis the result?
A.peep
B.bark
C.meow
D.Compilation fails.
E. Anexception is thrown at runtime.
Answer:E
Question 140
Given:
11.abstract class Vehicle { public int speed() { return 0; } }
12.class Car extends Vehicle { public int speed() { return 60; } }
13.class RaceCar extends Car { public int speed() { return 150; }}
......
21.RaceCar racer = new RaceCar();
22.Car car = new RaceCar();
23.Vehicle vehicle = new RaceCar();
24.System.out.println(racer.speed() + “, ‘ + car.speed()
25. +“, “+ vehicle.speed());
Whatis the result?
A. 0,0,0
B.150, 60, 0
C.Compilation fails.
D.150, 150, 150
E. Anexception is thrown at runtime.
Answer:D
Question 141
Given:
10.abstract class A {
11.abstract void al();
12.void a2() { }
13. }
14.class B extends A {
15.void a1() { }
16.void a2() { }
17. }
18.class C extends B { void c1() { } }
and:
A x =new B(); C y = new C(); A z = new C();
Whichfour are valid examples of polymorphic method calls? (Choose
four.)
A.x.a2();
B.z.a2();
C.z.c1();
D.z.a1();
E.y.c1();
F.x.a1();
Answer:ABDF
Question 142
Given:
10.interface A { void x(); }
11.class B implements A { public void x() { } public voidy() { } }
12.class C extends B { public void x() {} }
And:
20.java.util.List<A> list = new java.util.ArrayList<A>();
21.list.add(new B());
22.list.add(new C());
23.for (A a:list) {
24.a.x();
25.a.y();;
26. }
Whatis the result?
A. Thecode runs with no output.
B. Anexception is thrown at runtime.
C.Compilation fails because of an error in line 20.
D.Compilation fails because of an error in line 21.
E.Compilation fails because of an error in line 23.
F.Compilation fails because of an error in line 25.
Answer:F
Question 143
Given:
1.class SuperClass {
2.public A getA() {
3.return new A();
4. }
5. }
6.class SubClass extends SuperClass {
7.public B getA() {
8.return new B();
9. }
10. }
Whichis true?
A.Compilation will succeed if A extends B.
B.Compilation will succeed if B extends A.
C.Compilation will always fail because of an error in line 7.
D.Compilation will always fail because of an error in line 8.
Answer:B
Question 144
Given:
1.interface A { public void aMethod(); }
2.interface B { public void bMethod(); }
3.interface C extends A,B { public void cMethod(); }
4.class D implements B {
5.public void bMethod() { }
6. }
7.class E extends D implements C {
8.public void aMethod() { }
9.public void bMethod() { }
10.public void cMethod() { }
11. }
Whatis the result?
A.Compilation fails because of an error in line 3.
B.Compilation fails because of an error in line 7.
C.Compilation fails because of an error in line 9.
D. Ifyou define D e = new E(), then e.bMethod() invokes the version
ofbMethod() defined in Line 5.
E. Ifyou define D e = (D)(new E()), then e.bMethod() invokes the
versionof bMethod() defined in Line 5.
F. Ifyou define D e = (D)(new E()), then e.bMethod() invokes the
versionof bMethod() defined in Line 9.
Answer:F
Question 145
Given:
10.interface A { public int getValue() }
11.class B implements A {
12.public int getValue() { return 1; }
13. }
14.class C extends B {
15. //insert code here
16. }
Whichthree code fragments, inserted individually at line 15, make use
ofpolymorphism? (Choose three.)
A.public void add(C c) { c.getValue(); }
B.public void add(B b) { b.getValue(); }
C.public void add(A a) { a.getValue(); }
D.public void add(A a, B b) { a.getValue(); }
E.public void add(C c1, C c2) { c1.getValue(); }
Answer:BCD
Question 146
Given:
1.class ClassA {
2.public int numberOfinstances;
3.protected ClassA(int numberOfinstances) {
4.this.numberOflnstances = numberOfinstances;
5. }
6. }
7.public class ExtendedA extends ClassA {
8.private ExtendedA(int numberOfinstances) {
9.super(numberOflnstances);
10. }
11.public static void main(String[] args) {
12.ExtendedA ext = new ExtendedA(420);
13.System.out.print(ext.numberOflnstances);
14. }
15. }
Whichis true?
A. 420is the output.
B. Anexception is thrown at runtime.
C. Allconstructors must be declared public.
D.Constructors CANNOT use the private modifier.
E.Constructors CANNOT use the protected modifier.
Answer:A
Question 147
147. Given:
1.public class Base {
2.public static final String FOO = “foo”;
3.public static void main(String[] args) {
4.Base b = new Base();
5. Subs = new Sub();
6.System.out.print(Base.FOO);
7.System.out.print(Sub.FOO);
8.System.out.print(b.FOO);
9. System.out.print(s.FOO);
10.System.out.print(((Base)s).FOO);
11. }}
12.class Sub extends Base {public static final String FOO=bar;}
Whatis the result?
A.foofoofoofoofoo
B.foobarfoobarbar
C.foobarfoofoofoo
D.foobarfoobarfoo
E.barbarbarbarbar
F.foofoofoobarbar
G.foofoofoobarfoo
Answer:D
Question 148
Whichthree statements are true? (Choose three.)
A. Afinal method in class X can be abstract if and only if X is abstract.
B. Aprotected method in class X can be overridden by any subclass of
X.
C. A privatestatic method can be called only within other static
methodsin class X.
D. Anon-static public final method in class X can be overridden in any
subclassof X.
E. Apublic static method in class X can be called by a subclass of X
withoutexplicitly referencing the class X.
F. Amethod with the same signature as a private final method in class
X canbe implemented in a subclass of X.
G. Aprotected method in class X can be overridden by a subclass of A
onlyif the subclass is in the same package as X.
Answer:BEF
Question 149
Given:
1.class Pizza {
2.java.util.ArrayList toppings;
3.public final void addTopping(String topping) {
4.toppings.add(topping);
5. }
6. }
7.public class PepperoniPizza extends Pizza {
8.public void addTopping(String topping) {
9.System.out.println(”Cannot add Toppings”);
10. }
11.public static void main(String[] args) {
12.Pizza pizza = new PepperoniPizza();
13.pizza.addTopping(”Mushrooms”);
14. }
15. }
Whatis the result?
A.Compilation fails.
B.Cannot add Toppings
C. Thecode runs with no output.
D. ANullPointerException is thrown in Line 4.
Answer:A
Question 150
Given:
1.class Super {
2.private int a;
3.protected Super(int a) { this.a = a; }
4. }
.....
11.class Sub extends Super {
12.public Sub(int a) { super(a); }
13.public Sub() { this.a= 5; }
14. }
Whichtwo, independently, will allow Sub to compile? (Choose two.)
A.Change line 2 to:
publicint a;
B.Change line 2 to:
protectedint a;
C.Change line 13 to:
publicSub() { this(5); }
D.Change line 13 to:
publicSub() { super(5); }
E.Change line 13 to:
publicSub() { super(a); }
Answer:CD
Question 151
Clickthe Exhibit button.
1.public class SimpleCalc {
2.public int value;
3.public void calculate() { value += 7; }
4. }
And:
1.public class MultiCalc extends SimpleCalc {
2.public void calculate() { value -= 3; }
3.public void calculate(int multiplier) {
4. calculate();
5. super.calculate();
6. value *=multiplier;
7. }
8.public static void main(String[] args) {
9. MultiCalc calculator = new MultiCalc();
10. calculator.calculate(2);
11.System.out.println(”Value is: “+ calculator.value);
12. }
13. }
Whatis the result?
A.Value is: 8
B.Compilation fails.
C.Value is: 12
D.Value is: -12
E. Thecode runs with no output.
F. Anexception is thrown at runtime.
Answer:A
Question 152
Given:
10.public class Hello {
11.String title;
12.int value;
13.public Hello() {
14.title += “ World”;
15. }
16.public Hello(int value) {
17.this.value = value;
18.title = “Hello”;
19.Hello();
20. }
21. }
and:
30.Hello c = new Hello(5);
31.System.out.println(c.title);
Whatis the result?
A.Hello
B.Hello World
C.Compilation fails.
D.Hello World 5
E. Thecode runs with no output.
F. Anexception is thrown at runtime.
Answer:C
Question 153
Clickthe Exhibit button.
1.public class Car {
2.private int wheelCount;
3.private String vin;
4.public Car(String vin) {
5.this.vin = vin;
6.this.wheelCount = 4;
7. }
8.public String drive() {
9.return “zoom-zoom”;
10. }
11.public String getInfo() {
12.return “VIN: “+ vin + “wheels: “+ wheelCount;
13. }
14. }
And:
1.public class MeGo extends Car {
2.public MeGo(String vin) {
3.this.wheelCount = 3;
4. }
5. }
Whattwo must the programmer do to correct the compilation errors?
(Choosetwo.)
A.insert a call to this() in the Car constructor
B.insert a call to this() in the MeGo constructor
C.insert a call to super() in the MeGo constructor
D.insert a call to super(vin) in the MeGo constructor
E.change the wheelCount variable in Car to protected
F.change line 3 in the MeGoclass to super.wheelCount = 3;
Answer:DE
Question 154
Clickthe Exhibit button.
1.public class Employee {
2.String name;
3.double baseSalary;
4.Employee(String name, double baseSalary) {
5.this.name = name;
6.this.baseSalary = baseSalary;
7. }
8. }
And:
1.public class Salesperson extends Employee {
2.double commission;
3.public Salesperson(String name, double baseSalary,
4.double commission) {
5. //insert code here
6. }
7. }
Whichcode, inserted at line 7, completes the Salesperson constructor?
A.this.commission = commission;
B.superb();
commission= commission;
C.this.commission = commission;
superb();
D.super(name, baseSalary);
this.commission= commission;
E.super();
this.commission= commission;
F.this.commission = commission;
super(name,baseSalary);
Answer:D
Question 155
Given:
1.public class Blip {
2.protected int blipvert(int x) { return 0; }
3. }
4.class Vert extends Blip {
5. //insert code here
6. }
Whichfive methods, inserted independently at line 5, will compile?
(Choosefive.)
A.public int blipvert(int x) { return 0; }
B.private int blipvert(int x) { return 0; }
C.private int blipvert(long x) { return 0; }
D.protected long blipvert(int x) { return 0; }
E.protected int blipvert(long x) { return 0; }
F.protected long blipvert(long x) { return 0; }
G.protected long blipvert(int x, int y) { return 0; }
Answer:ACEFG
Question156
Given:
10.public class Foo {
11.public int a;
12.public Foo() { a = 3; }
13.public void addFive() { a += 5; }
14. }
and:
20.public class Bar extends Foo {
21.public int a;
22.public Bar() { a = 8; }
23.public void addFive() { this.a +=5; }
24. }
invokedwith:
30.Foo foo = new Bar();
31.foo.addFive();
32.System.out.println(”Value: “+ foo.a);
Whatis the result?
A.Value: 3
B.Value: 8
C. Value:13
D.Compilation fails.
E. Thecode runs with no output.
F. Anexception is thrown at runtime.
Answer:A
Question 157
Given:
10.public class SuperCaic {
11.protected static int multiply(int a, int b) { return a * b; }
12. }
and:
20.public class SubCalc extends SuperCalc {
21.public static int multiply(int a, int b) {
22.int c = super.multiply(a, b);
23.return c;
24. }
25. }
and:
30.SubCalc sc = new SubCalc();
31.System.out.println(sc.multiply(3,4));
32.System.out.println(SubCalc.multiply(2,2));
Whatis the result?
A. 12
4
B. Thecode runs with no output.
C. Anexception is thrown at runtime.
D.Compilation fails because of an error in line 21.
E.Compilation fails because of an error in line 22.
F.Compilation fails because of an error in line 31.
Answer:E
Question 158
Given:
1.public class Team extends java.util.LinkedList {
2.public void addPlayer(Player p) {
3.add(p);
4. }
5.public void compete(Team opponent) { /* more code here */ }
6. }
7.class Player { /* more code here */ }
Whichtwo are true? (Choose two.)
A.This code will compile.
B.This code demonstrates proper design of an is-a relationship.
C.This code demonstrates proper design of a has-a relationship.
D. AJava programmer using the Team class could remove Player
objectsfrom a Team object.
Answer:AD
Question 159
Whichfour are true? (Choose four.)
A.Has-a relationships should never be encapsulated.
B.Has-a relationships should be implemented using inheritance.
C.Has-a relationships can be implemented using instance variables.
D.Is-a relationships can be implemented using the extends keyword.
E.Is-a relationships can be implemented using the implements
keyword.
F. Therelationship between Movie and Actress is an example of an is-a
relationship.
G. Anarray or a collection can be used to implement a one-to-many
has-arelationship.
Answer:CDEG
Question 160
Whichtwo are true about has-a and is-a relationships? (Choose two.)
A.Inheritance represents an is-a relationship.
B.Inheritance represents a has-a relationship.
C.Interfaces must be used when creating a has-a relationship.
D.Instance variables can be used when creating a has-a relationship.
Answer:AD
Question 161
Given:
10.interface Jumper { public void jump(); }
......
20.class Animal {}
......
30.class Dog extends Animal {
31.Tail tail;
32. }
......
40.class Beagle extends Dog implements Jumper {
41.public void jump() { }
42. }
.......
50.class Cat implements Jumper {
51.public void jump() { }
52. }
Whichthree are true? (Choose three.)
A. Catis-a Animal
B. Catis-a Jumper
C. Dogis-a Animal
D. Dogis-a Jumper
E. Cathas-a Animal
F.Beagle has-a Tail
G.Beagle has-a Jumper
Answer:BCF
Question 162
Given:
1.import java.util.*;
2.public class Example {
3.public static void main(String[] args) {
4. //insert code here
5.set.add(new integer(2));
6.set.add(new integer(l));
7.System.out.println(set);
8. }
9. }
Whichcode, inserted at line 4, guarantees that this program will
output[1, 2]?
A. Setset = new TreeSet();
B. Setset = new HashSet();
C. Setset = new SortedSet();
D.List set = new SortedList();
E. Setset = new LinkedHashSet();
Answer:A
Question 163
Given:
1.import java.util.*;
2.public class PQ {
3.public static void main(String[] args) {
4.PriorityQueue<String> pq = new PriorityQueue<String>();
5.pq.add(”carrot”);
6.pq.add(”apple”);
7. pq.add(”banana”);
8.System.out.println(pq.poll() +”:” + pq.peek());
9. }
10. }
Whatis the result?
A.apple:apple
B.carrot:apple
C.apple:banana
D.banana:apple
E.carrot:carrot
F.carrot:banana
Answer:C
Question 164
Given:
1.import java.util.*;
2.public class WrappedString {
3.private String s;
4.public WrappedString(String s) { this.s = s; }
5.public static void main(String[] args) {
6.HashSet<Object> hs = new HashSet<Object>();
7.WrappedString ws1 = new WrappedString(”aardvark”);
8.WrappedString ws2 = new WrappedString(”aardvark”);
9.String s1 = new String(”aardvark”);
10.String s2 = new String(”aardvark”);
11.hs.add(ws1); hs.add(ws2); hs.add(s1); hs.add(s2);
12.System.out.println(hs.size()); } }
Whatis the result?
A. 0
B. 1
C. 2
D. 3
E. 4
F.Compilation fails.
G. Anexception is thrown at runtime.
Answer:D
Question 165
Clickthe Exhibit button.
1.import java.util.*;
2.public class TestSet {
3.enum Example { ONE, TWO, THREE }
4.public static void main(String[] args) {
5.Collection coll = new ArrayList();
6.coll.add(Example.THREE);
7.coll.add(Example.THREE);
8.coll.add(Example.THREE);
9.coll.add(Example.TWO);
10.coll.add(Example.TWO);
11.coll.add(Example.ONE);
12.Set set = new HashSet(coll);
13. }
14. }
Whichstatement is true about the set variable on line 12?
A. Theset variable contains all six elements from the coll collection,
andthe order is guaranteed to be preserved.
B. Theset variable contains only three elements from the coll
collection,and the order is guaranteed to be preserved.
C. Theset variable contains all six elements from the coil collection,
butthe order is NOT guaranteed to be preserved.
D. Theset variable contains only three elements from the coil
collection,but the order is NOT guaranteed to be preserved.
Answer:D
Question 166
Given:
1.public class Score implements Comparable<Score> {
2.private int wins, losses;
3.public Score(int w, int 1) { wins = w; losses = 1; }
4.public int getWins() { return wins; }
5.public int getLosses() { return losses; }
6.public String toString() {
7.return “<“ + wins + “,“ + losses + “>”;
8. }
9. //insert code here
10. }
Whichmethod will complete this class?
A.public int compareTo(Object o) {/*mode code here*/}
B.public int compareTo(Score other) {/*more code here*/}
C.public int compare(Score s1,Score s2){/*more code here*/}
D.public int compare(Object o1,Object o2){/*more code here*/}
Answer:B
Question 167
Aprogrammer has an algorithm that requires a java.util.List that
providesan efficient implementation of add(0,object), but does
NOTneed to support quick random access. What supports these
requirements?
A.java.util.Queue
B.java.util.ArrayList
C.java.util.LinearList
D.java.util.LinkedList
Answer:D
Question 168
Given:
11.public class Person {
12.private String name, comment;
13.private int age;
14.public Person(String n, int a, String c) {
15.name = n; age = a; comment = c;
16. }
17.public boolean equals(Object o) {
18.if(! (o instanceof Person)) return false;
19,Person p = (Person)o;
20.return age == p.age && name.equals(p.name);
21. }
22. }
Whatis the appropriate definition of the hashCode method in class
Person?
A.return super.hashCode();
B.return name.hashCode() + age * 7;
C.return name.hashCode() + comment.hashCode() /2;
D.return name.hashCode() + comment.hashCode() / 2 - age * 3;
Answer:B
Question 169
Given:
11.public class Key {
12.private long id1;
13.private long 1d2;
14.
15. //class Key methods
16. }
Aprogrammer is developing a class Key, that will be used as a key in
astandard java.util.HashMap. Which two methods should be
overriddento assure that Key works correctly as a key? (Choose two.)
A.public int hashCode()
B.public boolean equals(Key k)
C.public int compareTo(Object o)
D.public boolean equals(Object o)
E.public boolean compareTo(Key k)
Answer:AD
Question 170
Given:
11.public class Person {
12.private name;
13.public Person(String name) {
14.this.name = name;
15. }
16.public boolean equals(Object o) {
17. if(!o instanceof Person ) return false;
18.Person p = (Person) o;
19.return p.name.equals(this.name);
20. }
21. }
Whichis true?
A.Compilation fails because the hashCode method is not overridden.
B. AHashSet could contain multiple Person objects with the same
name.
C. AllPerson objects will have the same hash code because the
hashCodemethod is not overridden.
D. Ifa HashSet contains more than one Person object with
name=”Fred”,then removing another Person, also with name=”Fred”,
willremove them all.
Answer:B
Question 171
Given:
1.public class Person {
2.private String name;
3.public Person(String name) { this.name = name; }
4.public boolean equals(Person p) {
5.return p.name.equals(this.name);
6. }
7. }
Whichis true?
A. Theequals method does NOT properly override the Object.equals
method.
B.Compilation fails because the private attribute p.name cannot be
accessedin line 5.
C. Towork correctly with hash-based data structures, this class must
alsoimplement the hashCode method.
D.When adding Person objects to a java.util.Set collection, the equals
methodin line 4 will prevent duplicates.
Answer:A
Question 172
Whichtwo statements are true about the hashCode method? (Choose
two.)
A. ThehashCode method for a given class can be used to test for
objectequality and object inequality for that class.
B. ThehashCode method is used by the java.util.SortedSet collection
classto order the elements within that set.
C. ThehashCode method for a given class can be used to test for
objectinequality, but NOT object equality, for that class.
D. Theonly important characteristic of the values returned by a
hashCodemethod is that the distribution of values must follow a
Gaussiandistribution.
E. ThehashCode method is used by the java.util.HashSet collection
classto group the elements within that set into hash buckets for
swiftretrieval.
Answer:CE
Question 173
Given:
enumExample { ONE, TWO, THREE }
Whichis true?
A. Theexpressions (ONE == ONE) and ONE.equals(ONE) are both
guaranteedto be true.
B. Theexpression (ONE < TWO) is guaranteed to be true and
ONE.compareTo(TWO)is guaranteed to be less than one.
C. TheExample values cannot be used in a raw java.util.HashMap;
instead,the programmer must use a java.util.EnumMap.
D. TheExample values can be used in a java.util.SortedSet, but the
setwill NOT be sorted because enumerated types do NOT implement
java.lang.Comparable.
Answer:A
Question 174
Clickthe Exhibit button.
1.import java.util.*;
2.class KeyMaster {
3.public int i;
4.public KeyMaster(int i) { this.i = i; }
5.public boolean equals(Object o) { return i == ((KeyMaster)o).i; }
6.public int hashCode() { return i; }
7. }
8.public class MapIt {
9.public static void main(String[] args) {
10.Set<KeyMaster> set = new HashSet<KeyMaster>();
11.KeyMaster k1 = new KeyMaster(1);
12.KeyMaster k2 = new KeyMaster(2);
13.set.add(k1); set.add(k1);
14.set.add(k2); set.add(k2);
15.System.out.print(set.size() + “:”);
16.k2.i = 1;
17.System.out.print(set.size() + “:”);
18.set.remove(k1);
19.System.out.print(set.size() + “:”);
20.set.remove(k2);
21.System.out.print(set.size());
22. }
23. }
Whatis the result?
A.4:4:2:2
B.4:4:3:2
C.2:2:1:0
D.2:2:0:0
E.2:1:0:0
F.2:2:1:1
G.4:3:2:1
Answer:F
Question 175
Given:
1.import java.util.*;
2.public class Test {
3.public static void main(String[] args) {
4.List<String> strings = new ArrayList<String>();
5. //insert code here
6. }
7. }
Whichfour, inserted at line 5, will allow compilation to succeed?
(Choosefour.)
A.String s = strings.get(0);
B. Iteratori1 = strings.iterator();
C.String[] array1 = strings.toArray();
D.Iterator<String> i2 = strings.iterator();
E.String[] array2 = strings.toArray(new String[1]);
F.Iterator<String> i3 = strings.iterator<String>();
Answer:ABDE
Question 176
Given:
1.import java.util.*;
2.public class Old {
3.public static Object get()(List list) {
4.return list.get(0);
5. }
6. }
Whichthree will compile successfully? (Choose three.)
A.Object o = Old.get0(new LinkedList());
B.Object o = Old.get0(new LinkedList<?>());
C.String s = Old.getfl(new LinkedList<String>());
D.Object o = Old.get0(new LinkedList<Object>());
E.String s = (String)Old.get0(new LinkedList<String>());
Answer:ADE
Question 177
Given:
11.public static void append(List list) { list.add(”0042”); }
12.public static void main(String[] args) {
13.List<Integer> intList = new ArrayList<Integer>();
14.append(intList);
15.System.out.println(intList.get(0));
16. }
‘What is the result?
A. 42
B.0042
C. Anexception is thrown at runtime.
D.Compilation fails because of an error in line 13.
E.Compilation fails because of an error in line 14.
Answer:B
Question 178
Givena pre-generics implementation of a method:
11.public static int sum(List list) {
12.int sum = 0;
13.for ( Iterator iter = list.iterator(); iter.hasNext(); ) {
14.int i = ((Integer)iter.next()).intValue();
15.sum += i;
16. }
17.return sum;
18. }
Whichthree changes must be made to the method sum to use
generics?(Choose three.)
A.remove line 14
B.replace line 14 with “int i = iter.next();”
C.replace line 13 with “for (int i : intList) {“
D.replace line 13 with “for (Iterator iter : intList) {“
E.replace the method declaration with “sum(List<int> intList)”
F.replace the method declaration with “sum(List<Integer> intList)”
Answer:ACF
Question 179
Given:
classA{}
classB extends A {}
classC extends A {}
classD extends B {}
Whichthree statements are true? (Choose three.)
A. Thetype List<A> is assignable to List.
B. Thetype List<B> is assignable to List<A>.
C. Thetype List<Object> is assignable to List<?>.
D. Thetype List<D> is assignable to List<? extends B>.
E. Thetype List<? extends A> is assignable to List<A>.
F. Thetype List<Object> is assignable to any List reference.
G. Thetype List<? extends B> is assignable to List<? extends A>.
Answer:CDG
Question 180
Given:
11.public void addStrings(List list) {
12.list.add(”foo”);
13.list.add(”bar”);
14. }
Whatmust you change in this method to compile without warnings?
A. addthis code after line 11:
list =(List<String>) list;
B.change lines 12 and 13 to:
list.add<String>(”foo”);
list.add<String>(”bar”);
C.change the method signature on line 11 to:
publicvoid addStrings(List<? extends String> list) {
D.change the method signature on line 11 to:
publicvoid addStrings(List<? super String> list) {
E. Nochanges are necessary. This method compiles without warnings.
Answer:D
Question 181
Given:
1.public class Test {
2. public <T extends Comparable> T findLarger(T x,T y) {
3.if(x.compareTo(y) > 0) {
4.return x;
5. } else{
6.return y;
7. }
8. }
9. }
and:
22.Test t = new Test();
23. //insert code here
Whichtwo will compile without errors when inserted at line 23?
(Choosetwo.)
A.Object x = t.findLarger(123, “456”);
B. intx = t.findLarger(123, new Double(456));
C. intx = t.findLarger(123, new Integer(456));
D. intx = (int) t.findLarger(new Double(123), new Double(456));
Answer:AC
Question 182
Given:
11. //insert code here
12.private N min, max;
13.public N getMin() { return min; }
14.public N getMax() { return max; }
15.public void add(N added) {
16. if(min == null || added.doubleValue() <min.doubleValue())
17.min = added;
18. if(max == null ||added.doubleValue() > max.doubleValue())
19.max = added;
20. }
21. }
Whichtwo, inserted at line 11, will allow the code to compile? (Choose
two.)
A.public class MinMax<?> {
B.public class MinMax<? extends Number> {
C.public class MinMax<N extends Object> {
D.public class MinMax<N extends Number> {
E.public class MinMax<? extends Object> {
F.public class MinMax<N extends Integer> {
Answer:DF
Question 183
Aprogrammer must create a generic class MinMax and the type
parameterof MinMax must implement Comparable. Which
implementationof MinMax will compile?
A.class MinMax<E extends Comparable<E>> {
Emin=null;
E max=null;
publicMinMax() { }
publicvoid put(E value) { /* store min or max */ }
}
B.class MinMax<E implements Comparable<E>> {
Emin=null;
Emax=null;
publicMinMax() { }
publicvoid put(E value) { /* store min or max */ }
}
C. class MinMax<E extends Comparable<E>> {
<E> E min = null;
<E> E max = null;
public MinMax() { }
public<E> void put(E value) { /* store min or max */ }
}
D. class MinMax<E implementsComparable<E>> {
<E> E min = null;
<E> E max = null;
public MinMax() { }
public<E> void put(E value) { /* store min or max */ }
}
Answer:A
Question 184
Given:
1.public class Drink implements Comparable {
2.public String name;
3.public int compareTo(Object o) {
4.return 0;
5. }
6. }
and:
20.Drink one = new Drink();
21.Drink two = new Drink();
22.one.name= “Coffee”;
23.two.name= “Tea”;
23.TreeSet set = new TreeSet();
24.set.add(one);
25.set.add(two);
Aprogrammer iterates over the TreeSet and prints the name of each
Drinkobject.
Whatis the result?
A. Tea
B.Coffee
C.Coffee
Tea
D.Compilation fails.
E. Thecode runs with no output.
F. Anexception is thrown at runtime.
Answer:B
Question 185
Given:
11.List list = // more code here
12.Collections.sort(list, new MyComparator());
Whichcode will sort this list in the opposite order of the sort in line
12?
A.Collections.reverseSort(list, new MyComparator());
B.Collections.sort(list, new MyComparator());
list.reverse();
C.Collections.sort(list, new InverseComparator(
newMyComparator()));
D.Collections.sort(list, Collections.reverseOrder(
newMyComparator()));
Answer:D
Question 186
Given:
int[]myArray=newint[] {1, 2,3,4, 5};
Whatallows you to create a list from this array?
A.List myList = myArray.asList();
B.List myList = Arrays.asList(myArray);
C.List myList = new ArrayList(myArray);
D.List myList = Collections.fromArray(myArray);
Answer:B
Question 187
Given:
13.public static void search(List<String> list) {
14.list.clear();
15.list.add(”b”);
16.list.add(”a”);
17.list.add(”c”);
18.System.out.println(Collections.binarySearch(list, “a”));
19. }
Whatis the result of calling search with a valid List implementation?
A. 0
B. 1
C. 2
D. a
E. b
F. c
G. Theresult is undefined.
Answer:G
Question 188
Given:
1.import java.util.*;
2.
3.public class LetterASort {
4.public static void main(String[] args) {
5.ArrayList<String> strings = new ArrayList<String>();
6.strings.add(’aAaA”);
7.strings.add(”AaA”);
8.strings.add(’aAa”);
9.strings.add(”AAaa”);
10.Collections.sort(strings);
11.for (String s: strings) { System.out.print(s + “ “); }
12. }
13. }
Whatis the result?
A.Compilation fails.
B.aAaA aAa AAaa AaA
C.AAaa AaA aAa aAaA
D. AaAAAaa aAaA aAa
E. aAaAaA aAaA AAaa
F. Anexception is thrown at runtime.
Answer:C
Question 189
Given:
ArrayLista = new ArrayList();
containingthe values {“1”, “2”, “3”, “4”,“5”, “6”, “7”,“8”}
Whichcode will return 2?
A.Collections. sort(a, a.reverse());
intresult = Collections.binarySearch(a, “6”);
B.Comparator c = Collections.reverseOrder();
Collections.sort(a,c);
intresult = Collections.binarySearch(a, “6”);
C.Comparator c = Collections.reverseOrder();
Collections.sort(a,c);
intresult = Collections.binarySearch(a, “6”,c);
D.Comparator c = Collections.reverseOrder(a);
Collections.sort(a,c);
intresult = Collections.binarySearch(a, “6”,c);
E.Comparator c = new InverseComparator(new Comparator());
Collections.sort(a);
intresult = Collections.binarySearch(a, “6”,c);
Answer:C
Question 190
Given:
34.HashMap props = new HashMap();
35.props.put(”key45”, “somevalue”);
36.props.put(”key12”, “someother value”);
37.props.put(”key39”, “yetanother value”);
38.Set s = props.keySet();
39. //insert code here
What,inserted at line 39, will sort the keys in the props HashMap?
A.Arrays.sort(s);
B. s =new TreeSet(s);
C.Collections.sort(s);
D. s =new SortedSet(s);
Answer:B
Question 191
Givenclasses defined in two different files:
1.package util;
2.public class BitUtils {
3.public static void process(byte[]) { /* more code here */ }
4. }
1.package app;
2.public class SomeApp {
3.public static void main(String[] args) {
4.byte[] bytes = new byte[256];
5. //insert code here
6. }
7. }
Whatis required at line 5 in classSomeApp to use the process method
ofBitUtils?
A.process(bytes);
B.BitUtils.process(bytes);
C.util.BitUtils.process(bytes);
D.SomeApp cannot use methods in BitUtils.
E.import util.BitUtils.*; process(bytes);
Answer:C
Question
Givenclasses defined in two different files:
1.package util;
2.public class BitUtils {
3.private static void process(byte[] b) { }
4. }
1. packageapp;
2.public class SomeApp {
3.public static void main(String[] args) {
4.byte[] bytes = new byte[256];
5. //insert code here
6. }
7. }
Whatis required at line 5 in classSomeApp to use the process method
ofBitUtils?
A.process(bytes);
B.BitUtils.process(bytes);
C.app.BitUtils.process(bytes);
D.util.BitUtils.process(bytes);
E.import util.BitUtils. *; process(bytes);
F.SomeApp cannot use the process method in BitUtils.
Answer:F
Question 193
Givenclasses defined in two different files:
1. packagepackageA;
2.public class Message {
3.String getText() { return “text”; }
4. }
and:
1.package packageB;
2.public class XMLMessage extends packageA.Message {
3.String getText() { return “<msg>text</msg>”; }
4.public static void main(String[] args) {
5.System.out.println(new XMLMessage().getText());
6. }
7. }
Whatis the result of executing XMLMessage.main?
A.text
B.<msg>text</msg>
C. Anexception is thrown at runtime.
D.Compilation fails because of an error in line 2 of XMLMessage.
E.Compilation fails because of an error in line 3 of XMLMessage.
Answer:E
Question 194
Givena file GrizzlyBear.java:
1.package animals.mammals;
2.
3.public class GrizzlyBear extends Bear {
4.void hunt() {
5.Salmon s = findSalmon();
6.s.consume();
7. }
8. }
andanother file, Salmon.java:
1.package animals.fish;
2.
3.public class Salmon extends Fish {
4.void consume() { /* do stuff */ }
5. }
Assumeboth classes are defined in the correct directories for theft
packages,and that the Mammal class correctly defines the
findSalmon()method. Which two changes allow this code to compile
correctly?(Choose two.)
A. addpublic to the start of line 4 inSalmon.java
B. addpublic to the start of line 4 inGrizzlyBear.java
C. addimport animals.mammals.*; at line 2 inSalmon.java
D. addimport animals.fish.*; at line 2 inGrizzlyBear.java
E. addimport animals.fish.Salmon.*; at line 2 in GrizzlyBear.java
F. addimport animals.mammals.GrizzlyBear.*;at line 2 in Salmon.java
Answer:AD
Question 195
Givena class Repetition:
1.package utils;
2.
3.public class Repetition {
4.public static String twice(String s) { return s + s; }
5. }
andgiven another class Demo:
1. //insert code here
2.
3.public class Demo {
4.public static void main(String[] args) {
5.System.out.println(twice(”pizza”));
6. }
7. }
Whichcode should be inserted at line 1 of Demo.java to compile and
runDemo to print “pizzapizza”?
A.import utils.*;
B.static import utils.*;
C.import utils.Repetition.*;
D.static import utils.Repetition. *;
E.import utils.Repetition.twice();
F.import static utils.Repetition.twice;
G.static import utils.Repetition.twice;
Answer:F
Question 196
Given:
11.interface DeclareStuff{
12.public static final int EASY = 3;
13.void doStuff(int t); }
14.public class TestDeclare implements DeclareStuff {
15.public static void main(String [] args) {
16.int x=5;
17.new TestDeclare().doStuff(++x);
18. }
19.void doStuff(int s) {
20. s+= EASY + ++s;
21.System.out.println(”s “ + s);
22. }
23. }
Whatis the result?
A. s14
B. s16
C. s10
D.Compilation fails.
E. Anexception is thrown at runtime.
Answer:D
Question 197
Given:
1.interface DoStuff2 {
2.float getRange(int low, int high); }
3.
4.interface DoMore {
5.float getAvg(int a, int b, int c); }
6.
7.abstract class DoAbstract implements DoStuff2, DoMore { }
8.
9.class DoStuff implements DoStuff2 {
10.public float getRange(int x, int y) { return 3.14f; } }
11.
12.interface DoAll extends DoMore {
13.float getAvg(int a, int b, int c, int d); }
Whatis the result?
A. Thefile will compile without error.
B.Compilation fails. Only line 7 contains an error.
C.Compilation fails. Only line 12 contains an error.
D.Compilation fails. Only line 13 contains an error.
E.Compilation fails. Only lines 7 and 12 contain errors.
F. Compilationfails. Only lines 7 and 13 contain errors.
G.Compilation fails. Lines 7, 12, and 13 contain errors.
Answer:A
Question 198
Given:
11.public class Counter {
12.public static void main(String[] args) {
13.int numArgs = /* insert code here */;
14. }
15. }
andthe command line:
javaCounter one fred 42
Whichcode, inserted at line 13, captures the number of arguments
passedinto the program?
A.args.count
B.args.length
C.args.count()
D.args.length()
E.args.getLength()
Answer:B
Question 199
Givena correctly compiled class whose source code is:
1.package com.sun.sjcp;
2.public class Commander {
3.public static void main(String[] args) {
4. //more code here
5. }
6. }
Assumethat the class file is located in /foo/com/sun/sjcp/, the current
directoryis /foo/, and that the classpath contains “.“ (current
directory).
Whichcommand line correctly runs Commander?
A. java Commander
B. java com. sim. sjcp.Commander
C. java com/sun/sjcp/Commander
D. java -cp com.sun.sjcp Commander
E. java -cp com/sun/sjcp Commander
Answer:B
Question 200
Giventhe command line java Pass2 and:
15.public class Pass2 {
16.public void main(String [] args) {
17.intx=6;
18.Pass2 p = new Pass2();
19.p.doStuff(x);
20.System.out.print(” main x = “+ x);
21. }
22.
23.void doStuff(int x) {
24.System.out.print(” doStuffx = “+ x++);
25. }
26. }
Whatis the result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C.doStuffx = 6 main x = 6
D.doStuffx = 6 main x = 7
E.doStuffx = 7 main x = 6
F.doStuffx = 7 main x = 7
Answer:B
Question 201
Given:
15.public class Yippee {
16.public static void main(String [] args) {
17.for(int x = 1; x < args.length; x++) {
18.System.out.print(args[x] +“ “);
19. }
20. }
21. }
andtwo separate command line invocations:
javaYippee
javaYippee 1234
Whatis the result?
A. Nooutput is produced.
123
B. Nooutput is produced.
234
C. Nooutput is produced.
1234
D. Anexception is thrown at runtime.
123
E. Anexception is thrown at runtime.
234
F. Anexception is thrown at rijntime.
1234
Answer:B
Question 202
Given:
12.public class Yippee2 {
13.
14.static public void main(String [] yahoo) {
15.for(int x= 1; x<yahoo.length; x++) {
16.System.out.print(yahoo[x] + “ “);
17. }
18. }
19. }
andthe command line invocation:
javaYippee2 a b c
Whatis the result?
A.a b
B.b c
C.a bc
D.Compilation fails.
E. Anexception is thrown at runtime.
Answer:B
Question 203
Given:
11.public class Commander {
12.public static void main(String[] args) {
13.String myProp = /* insert code here */
14. System.out.println(myProp);
15. }
16. }
andthe command line:
java-Dprop.custom=gobstopper Commander
Whichtwo, placed on line 13, will produce the output gobstopper?
(Choosetwo.)
A.System.load(”prop.custom”);
B.System.getenv(”prop.custom”);
C.System.property(”prop.custom”);
D.System.getProperty(”prop.custom”);
E.System.getProperties().getProperty(”prop.custom”);
Answer:DE
Question 204
Clickthe Exhibit button.
11.class Payload {
12.private int weight;
13.public Payload(int wt) { weight = wt; }
13.public void setWeight(mt w) { weight = w; }
15.public String toString { return Integer.toString(weight); }
16. }
17.
18.public class TestPayload {
19.static void changePayload(Payload p) {
20. /*insert code here */
21. }
22.
23.public static void main(String[] args) {
24.Payload p = new Payload();
25.p.setWeight(1024);
26.changePayload(p);
27.System.out.println(”The value of p is “+ p);
28. }
29. }
Whichstatement, placed at line 20, causes the code to print “The
valueof p is 420.”?
A.p.setWeight(420);
B.p.changePayload(420);
C. p =new Payload(420);
D.Payload.setWeight(420);
E. p =Payload.setWeight(420);
F. p =new Payload();
p.setWeight(420);
Answer:A
Question 205
Clickthe Exhibit button.
1.public class Item {
2.private String desc;
3. publicString getDescription() { return desc; }
4.public void setDescription(String d) { desc = d; }
5.
6.public static void modifyDesc(Item item, String desc) {
7.item = new Item();
8.item.setDescription(desc);
9. }
10.public static void main(String[] args) {
11.Item it = new Item();
12.it.setDescription(”Gobstopper”);
13.Item it2 = new Item();
14.it2.setDescription(”Fizzylifting”);
15.modifyDesc(it, “Scrumdiddlyumptious”);
16.System.out.println(it.getDescription());
17.System.out.println(it2.getDescription());
18. }
19. }
Whatis the outcome of the code?
A.Compilation fails.
B.Gobstopper
Fizzylifting
C.Gobstopper
Scrumdiddlyumptious
D.Scrumdiddlyumptious
Fizzylifltng
E.Scrumdiddlyumptious
Scrumdiddlyumptious
Answer:B
Question 206
Given:
11.public class ItemTest {
12.private final mt id;
13.public ItemTest(int id) { this.id = id; }
14.public void updateId(int newId) { id = newId; }
15.
16.public static void main(String[] args) {
17.ItemTest fa = new ItemTest(42);
18.fa.updateId(69);
19.System.out.println(fa.id);
20. }
21. }
Whatis the result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C. Theattribute id in the Item object remains unchanged.
D. Theattribute id in the Item object is modified to the new value.
E. Anew Item object is created with the preferred value in the id
attribute.
Answer:A
Question 207
Clickthe Exhibit button.
10.class Inner {
11.private int x;
12.public void setX( int x) { this.x = x; }
13.public int getX() { return x; }
14. }
15.
16.class Outer {
17.private Inner y;
18.public void setY( Inner y) { this.y = y; }
19.public Inner getY() { return y; }
20. }
21.
22.public class Gamma {
23.public static void main( String[] args) {
24.Outer o = new Outer();
25.Inner i = new Inner();
26.int n=10;
27. i.setX(n);
28.o.setY(i);
29. //insert code here
30.System.out.println( o.getY().getX());
31. }
32. }
Whichthree code fragments, added individually at line 29, produce the
output100? (Choose three.)
A. n =100;
B.i.setX( 100);
C.o.getY().setX( 100);
D. i =new Inner(); i.setX( 100);
E.o.setY( i); i = new Inner(); i.setX( 100);
F. i =new Inner(); i.setX( 100); o.setY( i);
Answer:BCF
Question 208
Clickthe Exhibit button.
10.class Foo {
11.private int x;
12.publicFoo(intx){this.x=x; }
13.public void setX( int x) { this.x = x; }
14.public int getX() { return x; }
15. }
16.
17.public class Gamma {
18.
19.static Foo fooBar( Foo foo) {
20.foo = new Foo( 100);
21.return foo;
22. }
23.
24.public static void main( String[] args) {
25. Foofoo = new Foo( 300);
26.System.out.print( foo.getX() + “-“);
27.
28.Foo fooFoo = fooBar( foo);
29.System.out.print( foo.getX() + “-“);
30.System.out.print( fooFoo.getX() + “-“);
31.
32.foo = fooBar( fooFoo);
33.System.out.print( foo.getX() + “-“);
34.System.out.prmt( fooFoo.getX());
35. }
36. }
Whatis the output of this program?
A.300-100-100-100-100
B.300-300-100-100-100
C.300-300-300-100-100
D.300-300-300-300-100
Answer:B
Question 209
Given:
11.public void genNumbers() {
12.ArrayList numbers = new ArrayList();
13.for (int i=0; i<10; i++) {
14.int value = i * ((int) Math.random());
15.Integer intObj = new Integer(value);
16.numbers.add(intObj);
17. }
18.System.out.println(numbers);
19. }
Whichline of code marks the earliest point that an object referenced
byintObj becomes a candidate for garbage collection?
A.Line 16
B.Line 17
C.Line 18
D.Line 19
E. Theobject is NOT a candidate for garbage collection.
Answer:D
Question 210
Given:
11.rbo = new ReallyBigObject();
12. //more code here
13.rbo = null;
14. /*insert code here */
Whichstatement should be placed at line 14 to suggest that the virtual
machineexpend effort toward recycling the memory used by the
objectrbo?
A.System.gc();
B.Runtime.gc();
C.System.freeMemory();
D. Runtime.getRuntime().growHeap();
E.Runtime.getRuntime().freeMemory();
Answer:A
Question 211
Given:
11.class Snoochy {
12.Boochybooch;
13.public Snoochy() { booch = new Boochy(this); }
14. }
15.
16.class Boochy {
17.Snoochy snooch;
18.public Boochy(Snoochy s) { snooch = s; }
19. }
Andthe statements:
21.public static void main(String[] args) {
22.Snoochy snoog = new Snoochy();
23.snoog = null;
24. //more code here
25. }
Whichstatement is true about the objects referenced by snoog,
snooch,and booch immediately after line 23 executes?
A.None of these objects are eligible for garbage collection.
B.Only the object referenced by booch is eligible for garbage
collection.
C.Only the object referenced by snoog is eligible for garbage
collection.
D. Onlythe object referenced by snooch is eligible for garbage
collection.
E. Theobjects referenced by snooch and booch are eligible for garbage
collection.
Answer:E
Question 212
Given:
1.public class GC {
2.private Object o;
3.private void doSomethingElse(Object obj) { o = obj; }
4.public void doSomething() {
5.Object o = new Object();
6.doSomethingElse(o);
7. o =new Object();
8.doSomethingElse(null);
9.o=null;
10. }
11. }
Whenthe doSomething method is called, after which line does the
Objectcreated in line 5 become available for garbage collection?
A.Line 5
B.Line 6
C.Line 7
D.Line 8
E.Line 9
F.Line 10
Answer:D
Question 213
Whichtwo are true? (Choose two.)
A. Afinalizer may NOT be invoked explicitly.
B. Thefinalize method declared in class Object takes no action.
C.super.finalize() is called implicitly by any overriding finalize method.
D. Thefinalize method for a given object will be called no more than
onceby the garbage collector.
E. Theorder in which finalize will be called on two objects is based on
theorder in which the two objects became finalizable.
Answer:BD
Question 214
Aclass games.cards.Poker is correctly defined in the jar file Poker.jar.
A userwants to execute the main method of Poker on a UNIX system
usingthe command:
javagames.cards.Poker
Whatallows the user to do this?
A. putPoker.jar in directory /stuff/java, and set the CLASSPATH to
include/stuff/java
B. putPoker.jar in directory /stuff/java, and set the CLASSPATH to
include/stuff/java/*.jar
C. PutPoker.jar in directory /stuff/java, and set the CLASSPATH to
include/stuff/java/Poker.jar
D. putPoker.jar in directory /stuff/java/games/cards, and set the
CLASSPATHto include /stuff/java
E. putPoker.jar in directory /stuff/java/games/cards, and set the
CLASSPATHto include /stuffijava/*.jar
F. putPoker.jar in directory /stuff/java/games/cards, and set the
CLASSPATHto include /stuff/java/Poker.jar
Answer:C
Question 215
Clickthe Exhibit button.
Giventhe fully-qualified class names:
com.foo.bar.Dog
com.foo.bar.blatz.Book
com.bar.Car
com.bar.blatz.Sun
Whichgraph represents the correct directory structure for a JAR file
fromwhich those classes can be used by the compiler and JYM?
A. Jar A
B. Jar B
C. Jar C
D. Jar D
E. Jar E
Answer: A
Question 216
Adeveloper is creating a class Book that needs to access class Paper.
ThePaper class is deployed in a JAR named myLib.jar. Which three,
takenindependently, will allow the developer to use the Paper class
whilecompiling the Book class? (Choose three.)
A. TheJAR file is located at $JAVA_HOME/jre/classes/myLib.jar.
B. TheJAR file is located at $JAVA_HOME/jre/lib/ext/myLib.jar.
C. TheJAR file is located at /foo/myLib.jar and a classpath
environmentvariable is set that includes /foo/myLib.jar/Paper.class.
D. TheJAR file is located at /foo/myLib.jar and a classpath
environmentvariable is set that includes /foo/myLib.jar.
E. TheJAR file is located at /foo/myLib.jar and the Book class is
compiledusing javac -cp /foo/myLib.jar/Paper Book.java.
F. TheJAR file is located at /foo/myLib.jar and the Book class is
compiledusing javac -d /foo/myLib.jar Book.java.
G. TheJAR file is located at /foo/myLib.jar and the Book class is
compiledusing javac -classpath /foo/myLib.jar Book.java.
Answer:BDG
Question 217
Given:
1. packagecom.company.application;
2.
3.public class MainClass {
4.public static void main(String[] args) { }
5. }
AndMainClass exists in the /apps/com/company/application directory.
Assumethe CLASSPATH environment variable is set to “.“ (current
directory).Which two java commands entered at the command line
willrun MainClass? (Choose two.)
A.java MainClass if run from the /apps directory
B.java com.company.application.MainClass if run from the /apps
directory
C.java -classpath /apps com.company.application.MainClass if run
fromany directory
D.java -classpath . MainClass if run from the
/apps/com/company/applicationdirectory
E.java -classpath /apps/com/company/application:. MainClass if run
fromthe /apps directory
F.java com.company.application.MainClass if run from the
/apps/com/company/applicationdirectory
Answer:BC
Question 218
A UNIXuser named Bob wants to replace his chess program with a
newone, but he is hot sure where the old one is installed. Bob is
currentlyable to run a Java chess program starting from his home
directory/home/bob using the command:
java-classpath /test:/home/bob/downloads/* .jar games.Chess
Bob’sCLASSPATH is set (at login time) to:
/usr/lib:/home/bob/classes:/opt/java/lib:/opt/java/lib/*.jar
Whatis a possible location for the Chess.class file?
A./test/Chess.class
B./home/bob/Chess.class
C./test/games/Chess.class
D./usr/lib/games/Chess.class
E./home/bob/games/Chess.class
F.inside jarfile /opt/java/lib/Games.jar (with a correct manifest)
G.inside jarfile /home/bob/downloads/Games.jar (with a correct
manifest)
Answer:C
Question 219
Given:
11.public static void test(String str) {
12.if(str == null | str.lellgth() == 0) {
13.System.out.println(”String is empty”);
14. }else {
15.System.out.println(”String is not empty”);
16. }
17. }
Andthe invocation:
31.test(llull);
Whatis the result?
A. Auexception is thrown at runtime.
B.“String is empty” is printed to output.
C.Compilation fails because of au error in line 12.
D.“String is not empty” is printed to output.
Answer:A
Question 220
Given:
11.public static void test(String str) {
12.int check = 4;
13. if(check = str.length()) {
14.System.out.print(str.charAt(check -= 1) +“, “);
15. }else {
16.System.out.print(str.charAt(0) + “, “);
17. }
18. }
and theinvocation:
21.test(”four”);
22.test(”tee”);
23.test(”to”);
Whatis the result?
A. r, t, t,
B. r, e, o,
C. Compilation fails.
D. Anexception is thrown at runtime.
Answer:C
Question 221
Given:
10.public class MyClass {
11.
12.public Integer startingI;
13.public void methodA() {
14.Integer i = new Integer(25);
15.startingI = i;
16.methodB(i);
17. }
18.private void methodB(Integer i2) {
19. i2= i2.intValue();
20.
21. }
22. }
IfmethodA is invoked, which two are true at line 20? (Choose two.)
A. i2== startingI returns true.
B. i2== startingI returns false.
C.i2.equals(startingI) returns true.
D.i2.equals(startingI) returns false.
Answer:BC
Question 222
222.Given:
11.class Cup { }
12.class PoisonCup extends Cup { }
21.public void takeCup(Cup c) {
22.if(c instanceof PoisonCup) {
23.System.out.println(”Inconceivable!”);
24. }else if(c instanceof Cup) {
25.System.out.println(”Dizzying intellect!”);
26. }else {
27.System.exit(0);
28. }
29. }
Andthe execution of the statements:
Cupcup = new PoisonCup();
takeCup(cup);
Whatis the output?
A.Inconceivable!
B.Dizzying intellect!
C. Thecode runs with no output.
D. Anexception is thrown at runtime.
E.Compilation fails because of an error in line 22.
Answer:A
Question 223
Given:
11.String[] elements = { “for”, “tea”, “too” };
12.String first = (elements.length > 0)? elements[0] null;
Whatis the result?
A.Compilation fails.
B. Anexception is thrown at runtime.
C. Thevariable first is set to null.
D. Thevariable first is set to elements[0].
Answer:D
Question 224
Given:
42.public class ClassA {
43.public int getValue() {
44.intvalue=0;
45.boolean setting = true;
46.String title=”Hello”;
47. if(value || (setting && title == “Hello”)) { return 1; }
48. if(value == 1 & title.equals(”Hello”)) { return 2; }
49. }
50. }
And:
70.ClassA a = new ClassA();
71.a.getValue();
Whatis the result?
A. 1
B. 2
C.Compilation fails.
D. Thecode runs with no output.
E. Anexception is thrown at runtime.
Answer:C