Java Object类 instanceof关键字 练习：判断是否…

package com.swift;

public class Same_Person_Test {

    public static void main(String[] args) {
        /*
         * Object判断是否是同一人
         */
        Person per1=new Person("zhangsan",30);
        Person per2=new Person("lisi",27);
        Person per3=new Person("lisi",27);
        
        System.out.println(per3.equals(per2));
        System.out.println(per1.equals(per2));
        System.out.println(per2.equals(per2));
    }

}

class Person{
    private String name;
    private int 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;
    }
    public Person(String name, int age) {
        super();
        this.name = name;
        this.age = age;
    }
    
    public boolean equals(Object obj) {
        if(this==obj) {
            return true;
        }
        if(obj instanceof Person) {
            Person per=(Person) obj;
            return this.getName().equals(per.getName())&&this.getAge()==per.getAge();
        }
        return false;
        
    }
    
}

package com.swift;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.ListIterator;

public class Same_Person_Test {

    public static void main(String[] args) {
        /*
         * Object判断是否是同一人 集合按照人的年龄排序，如果年龄相同按名字的字母顺序升序
         */
        Person[] per =new Person[5];
        per[1]=new Person("zhangsan",30);
        per[2]=new Person("lisi",27);
        per[3]=new Person("wangwu",19);
        per[4]=new Person("wangliu",19);
        per[0]=new Person("tianqi",37);
        List<Person> list=new ArrayList<Person>();
        for(Person person:per) {
            list.add(person);
        }
        
        System.out.println(per[3].equals(per[2]));
        System.out.println(per[1].equals(per[2]));
        System.out.println(per[2].equals(per[2]));
        
        Collections.sort(list, new Comparator<Person>() {

            @Override
            public int compare(Person arg0, Person arg1) {
                int num=arg0.getAge()-arg1.getAge();
                return num==0?arg0.getName().compareTo(arg1.getName()):num;
            }
        });
        
        ListIterator it=list.listIterator();
        while(it.hasNext()) {
            Person p=(Person) it.next();
            System.out.println(p.toString());
        }
    }

}

class Person{
    private String name;
    private int 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;
    }
    public Person(String name, int age) {
        super();
        this.name = name;
        this.age = age;
    }
    
    public boolean equals(Object obj) {
        if(this==obj) {
            return true;
        }
        if(obj instanceof Person) {
            Person per=(Person) obj;
            return this.getName().equals(per.getName())&&this.getAge()==per.getAge();
        }
        return false;
    }
    @Override
    public String toString() {
        return "Person [name=" + name + ", age=" + age + "]";
    }
    
    
}