为什么改变值后,无法删除?
package mytest;
import java.util.HashSet;
import java.util.Set;
public class Key {
int i;
public Key(int i) {
this.i = i;
}
public int hashCode() {
return i;
}
public boolean equals(Object obj) {
return i == ((Key)obj).i;
}
public static void main(String[] args) {
Set<Key> set = new HashSet<Key>();
Key k1 = new Key(1);
Key k2 = new Key(2);
set.add(k1);
set.add(k2);
System.out.println("原来:"+set);
set.remove(k1);
System.out.println("删除k1后:"+set);
k2.i = 1;
System.out.println("改变k2.i为1后:"+set);
boolean f = set.remove(k2);//这里为什么失败?
System.out.println("是否删除k2?:"+f);
System.out.println("删除操作后:"+set);
k2.i = 2;
System.out.println("改变k2.i为2后:"+set);
f = set.remove(k2);
System.out.println("是否删除k2?:"+f);
System.out.println("删除操作后:"+set);
}
}