类集HashSet

HashSet

import java.util.HashSet;

public class TreeSetDemo1 {

public static void main(String[] args) {

HashSet<Dog> ts = new HashSet<Dog>();
ts.add(new Dog("1", 33));
ts.add(new Dog("2", 2));
ts.add(new Dog("2", 44));
ts.add(new Dog("2", 12));
ts.add(new Dog("3", 13));
ts.add(new Dog("4", 14));
System.out.println(ts);
}

}

class Dog{
private String name;
private int age;

public Dog(String name, int age) {
this.name = name;
this.age = age;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public int getAge() {
return age;
}

public void setAge(int age) {
this.age = age;
}

public String toString() {
return (this.name + ":" + this.age);
}
public boolean equals(Object obj){
//首先判断是不是我们要判断的类型
if(!(obj instanceof Dog)){
return false;
}
//判断是不是不同名字，但是指向了同一个
if(this == obj ){
return true;
}
//判断是不同的对象，但是值确是一样
Dog d = (Dog)obj;
if(this.age == d.getAge()&&this.getName()==d.getName()){
return true;
}else{
return false;
}

}

public int hashCode(){
return this.name.hashCode();
//return this.name.hashCode()*this.age;
}

}