SCJP真题库更新20
QUESTION 96
Given:
What is the result?
A. Compilation fails
B. Pi is approximately 3.
C. Pi is approximately 3.141593.
D. An exception is thrown at runtime.
Answer: ( D )
%d打印一个整数，要求接受一个整数 抛IllegalFormatConversionException
QUESTION 97
Given:
What is the result?
A. int Long
B. Short Long
C. Compilation fails
D. An exception is thrown at runtime.
Answer: ( A )
QUESTION 98
Chain these constructors to create objects to read from a file named "in" and to
write to a file named "out".
Answer: ( )
new BufferedReader( new FileReader( “in”));
new PrintWriter( new BufferedWriter( new FileWriter( “out”)));
QUESTION 99
Place the code fragments into position to use a BufferedReader to read in an entire text file.
Answer: ( )
class PrintFile{
public static void main(String[] args){
BufferedReader buffReader = null;
//more code here to initialize buffReader
try{
String temp;
while((temp=buffReader.readLine()) !=null){
System.out.println(temp);
}
}catch (IOException e){
e.printStackTrace();
}
}
}
QUESTION 100
Given this method in a class:
Which statement is true?
A. This code is NOT thread-safe.
B. The programmer can replace StringBuffer with StringBuilder with no other changes.
C. This code will perform poorly. For better performance, the code should be rewritten:
return "<" + this.name + ">";
D. This code will perform well and converting the code to use StringBuilder will not
enhance the performance.
Answer: ( B )