java HashMap 內存泄漏

import java.util.HashMap;
import java.util.Map;

public class HashMapOver {

    public static void main(String[] args) {
        Map<Person, Integer> map = new HashMap<Person, Integer>();
        Person p = new Person("zhangsan", 12);
        System.out.println(map.size());
        map.put(p, 1);
        System.out.println(p.hashCode());
        p.setName("lisi"); // 因為p.name參與了hash值的計算，修改了之后hash值發生了變化，所以下面刪除不掉
        map.remove(p);
        System.out.println(p.hashCode());
        System.out.println(map.size());
    }
}

class Person {
    private String name;
    private int age;

    public Person(String name, int age) {
        super();
        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;
    }

    @Override
    public boolean equals(Object obj) {
        // TODO Auto-generated method stub
        return super.equals(obj);
    }

    @Override
    public int hashCode() {
        return name.hashCode() * 123;
    }
}

 

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