zengequal.java

苏州大学java学习的ppt课件

/* 曾海 2004-10 判断对象相等实例，超越了equals  hascode*/

public class  ZengEqual
{
	public static void main(String[] args) 
	{
		A a1 = new A(2);
		A a2  = new A(3);
		A a3 = new A(3);
       if ( a1.equals(a2))
		System.out.println("equal!");
		else
		System.out.println("No");
	}
}

class A
{
 public int number=0;
 public A(int i){
	   number=i;
 }
	public int hashCode(){
		return number;
	}
    public boolean equals(Object obj) {
   
     if ( ((A)obj).number==number)
		 return true;
     else
		 return false;
	};
}