Áù¡¢javaµÄÃæÏò¶ÔÏó³ÌÐòÉè¼Æ(Ïê½âequals·½·¨)

Áù¡¢javaµÄÃæÏò¶ÔÏó³ÌÐòÉè¼Æ(Ïê½âequals·½·¨)
/**
 * Ïê½âequals·½·¨. 
 */
class Equals
{
 private int i;
 public void setI(int i)
 {
  this.i = i;
 }
 public Equals()
 {
  i = 1;
 }
 public Equals(int i)
 {
  this.i = i;
 }
}
class ChangeEquals
{
 private int i;
 public void setI(int i)
 {
  this.i = i;
 }
 public ChangeEquals()
 {
  i = 1;
 }
 public ChangeEquals(int i)
 {
  this.i = i;
 }
 //¸²¸Ç¸¸ÀàµÄequals·½·¨,±È½ÏÁ½¸ö¶ÔÏóµÄ³ÉÔ±±äÁ¿iµÄÖµ
 //Èç¹ûÏàµÈ·µ»Øtrue,²»µÈ·µ»Øfalse.
 public boolean equals(Object obj)
 {
  ChangeEquals ce = null;;
  if(obj instanceof ChangeEquals)
  {
   ce = (ChangeEquals)obj;
   if(this.i == ce.i)
    return true;
   else
    return false;
  }
  return false;
 }
}
public class EqualsTest {
 /**
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub
  /*µ÷ÓÃÎÒÃÇ´´½¨µÄÀàµÄĬÈÏequals·½·¨*/
  System.out.println("µ÷ÓÃÎÒÃÇ´´½¨µÄÀàµÄĬÈÏequals·½·¨");
  Equals e1 = new Equals();//²ÉÓÃĬÈϹ¹Ôì»ú
  Equals e2 = new Equals();
  System.out.println(e2.equals(e1));//false;
  Equals e3 = new Equals(20);//²ÉÓôø²ÎÊýµÄ¹¹Ôì»ú
  Equals e4 = new Equals(20);
  System.out.println(e3.equals(e4));//false
  //ͨ¹ýÒÔÉÏʵÀýÖ¤Ã÷,EqualsÀàµÄ³ÉÔ±±äÁ¿i²¢²»ÊÇequals·½·¨ÅжϵÄÒÀ¾Ý.Ô­ÒòÈçÏÂ:
  /*
  ÎÒÃÇÏÈÀ´¿´¿´java.lang.ObjectÕâ¸öÀàÖеÄequals·½·¨.
  public boolean equals(Object obj)
  {
    return (this == obj);
  }//~~~³ö×ÔjavaµÄlang°ü
  Ob