两个值相同的Integer对象的比较

package com.jj.test;

import java.util.Objects;

public class ObjectEqualsTest {
    public static final Integer COUNT_NONE = 0;
    public static void main(String[] args){
        Integer a=new Integer(0);
        boolean bool = Objects.equals(a,COUNT_NONE);
        a.equals(COUNT_NONE);
        System.out.println(a==COUNT_NONE);/*1*/
        System.out.println(bool);/*2*/
        System.out.println(a.equals(COUNT_NONE));/*3*/
    }
}

false
true
true

  public static boolean equals(Object a, Object b) {
        return (a == b) || (a != null && a.equals(b));
    }

public boolean equals(Object obj) {
        if (obj instanceof Integer) {
            return value == ((Integer)obj).intValue();
        }
        return false;
    }