java基础小程序

public class ClassMain {
public static void main(String args[]) {
/********第一段*******************/
ClassE a = new ClassE();
ClassE b = new ClassE();

a.i=1;
b.i=2;
b=a;
b.i=3;

System.out.println(a.i);

/********第二段*******************/
ClassE c = new ClassE();
ClassMain cm = new ClassMain();
c.i=1;
cm.revalue(c);
System.out.println(c.i);

String s1 = new String();
String s2 = new String();

/********第三段*******************/
s1="a";
s2="b";
s1=s2;
s2="c";
System.out.println(s1);

}

public void revalue(ClassE c) {
ClassE d = new ClassE();
d.i=2;
c=d;
d.i=3;
}
}
class ClassE {
int i=0;
} 

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