java对象排序（Comparable）详细实例

对象实现Comparable接口

public class Field implements Comparable<Field>{
    private String name;
    private int age;  

    public Field() {
    }
    public Field(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;
    }
    @Override
    public int compareTo(Field o) {
        // TODO Auto-generated method stub
         // 先按age排序
        if (this.age > o.getAge()) {
            return (this.age - o.getAge());
        }
        if (this.age < o.getAge()) {
            return (this.age - o.getAge());
        }  

        // 按name排序
        if (this.name.compareTo(o.getName()) > 0) {
            return 1;
        }
        if (this.name.compareTo(o.getName()) < 0) {
            return -1;
        }  

        return 0;
    }  

}  

测试test

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

public class Test {
    public static void main(String[] args) {
        Field f1 = new Field("tony", 19);
        Field f2 = new Field("jack", 16);
        Field f3 = new Field("tom", 80);
        Field f4 = new Field("jbson", 44);
        Field f5 = new Field("jason", 44);  

        List<Field> list = new ArrayList<Field>();
        list.add(f1);
        list.add(f3);
        list.add(f4);
        list.add(f2);
        list.add(f5);
        Collections.sort(list);  

        for (Field o : list) {
            System.out.println(o.getAge() + "-->" + o.getName());
        }
    }
}