java基础-equals和==

public boolean equals(Object obj) {        return (this == obj);    }

public class Person {private String name;public Person(String name) {super();this.name = name;}public String getName() {return name;}public void setName(String name) {this.name = name;}}

public class TestObject {public static void main(String[] args) {Person p1 = new Person("李");Person p2 = new Person("李");System.out.println(p1 == p2);System.out.println(p1.equals(p2));String a = "123";String b = new String("123");System.out.println(a==b);System.out.println(a.equals(b));}}

System.out.println(p1 == p2);  false
p1和p2的对象是不一样的，所以为false
System.out.println(p1.equals(p2)); false
该比较为object的判断，实质是==判断，若要只是比较内容相等，那么Person对象就得重写equals方法
System.out.println(a==b); false
a和b的对象是不一样的，所以为false
System.out.println(a.equals(b)); //true
string的方法里就已经重写了equals方法，所以为true