Java中"=="与equals()方法的区别

例如：int a1=1,a2=3;

boolean b1=a1==a2; //”==”的操作元为基本类型，b1值为false

String str1=”Hello”,str2=”World”;

boolean b2=str1==str2; //”==”的操作元为引用类型，b2的值为false

如：

class Creature {Creature() {}}class Animal extends Creature {Animal() {}}class Dog extends Animal {Dog() {}}class Cat extends Animal {Cat() {}}public class IntegerTest {public static void main(String[] args) {Dog dog = new Dog();Creature creature = dog;Animal animal = new Cat();System.out.println(dog == animal);System.out.println(dog == creature);}}结果为：falsetrue 

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5．只要两个对象都是同一个类的对象，并且它们变量属性相同，则结果为true,否则为false.

class TestInteger{private String name;TestInteger(String name){this.name=name;}boolean equal(Object o){if(this==o){return true;}if(!(o instanceof TestInteger)){return false;}final TestInteger other=(TestInteger)o;if(this.name.equals(other.name)){return true;}else{return false;}}}public class TestIntegerOne {public static void main(String[] args) {TestInteger person1=new TestInteger("Tom");TestInteger person2=new TestInteger("Tom");System.out.println(person1==person2);System.out.println(person1.equal(person2));}} 结果为：falsetrue

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