java中的equals工具包和hashcode

package com.te.jdkapi;

import com.sun.xml.internal.ws.api.model.wsdl.WSDLOutput;

import java.util.Objects;

/*
学习equals的方法
 */
public class Study_Equels {
    public static void main(String[] args) {
        Animal a1 = new Animal();
        Animal a2 = new Animal();
        System.out.println(a1==a2);
    }

}

class Animal {
    private String name;
    private int age;

    @Override
    public boolean equals(Object o) {
        if (o instanceof Animal){ // 返回True，当前比较两个对象类型相同
            // 比较两个对象的属性值是否相同
            Animal st = (Animal) o;  // 将传递过来的Object类向下强转为Animal类
            if (this.name == st.name && this.age == st.age){
                return true;
            }
        }
        return false;
    }

    @Override
    public int hashCode() {
        return Objects.hash(name, age);
    }

    public Animal() {
    }
    public Animal(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;
    }
}

通常java自带的equals方法不满足我们的需要，需要重写。我们不需要通过hashcode来判断两个类是否相等