重写equals方法

 1 package object;
 2 
 3 public class Test {
 4     public static void main(String[] args) {
 5         Person person1=new Person();
 6         person1.setName("ZTT");
 7         
 8         Person person2=new Person();
 9         person2.setName("ZTT");
10         
11         System.out.println(person1.name.equals(person2.name));//结果:true
12         
13     }
14 }

我们都知道equals比较的是内容，很明显上面的结果是true.

然而equals方法的参数对象是Object,那Person也是对象，如果直接使得person.equals(person2)结果又如何呢，答案是false,因为在equals方法中用的是==，比较的是地址，让我们重写Person的equals方法

使得结果为true.

重写equals方法：

 1 package object;
 2 
 3 public class Person {
 4     public String getName() {
 5         return name;
 6     }
 7     public void setName(String name) {
 8         this.name = name;
 9     }
10     public int getAge() {
11         return age;
12     }
13     public void setAge(int age) {
14         this.age = age;
15     }
16     String name;
17     int age;
18     
19     @Override
20     public boolean equals(Object obj) {
21         Person person=(Person)obj;
22         /*if(person.name.equals(name)&&person.age==age){
23             return true;
24         }
25         return false;*/
26         return person.name.equals(name)&&person.age==age;
27         
28     }
29     
30 }

 1 package object;
 2 
 3 public class Test {
 4     public static void main(String[] args) {
 5         Person person1=new Person();
 6         person1.setName("ZTT");
 7         person1.setAge(10);
 8         
 9         Person person2=new Person();
10         person2.setName("ZTT");
11         person2.setAge(10);
12         
13         System.out.println(person1.equals(person2));//结果:true
14         
15     }
16 }