普通java类(排序)实现Comparable接口重写CompareTo方法

package test; 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) { // 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; } }

package test; import java.util.ArrayList; import java.util.Collections; import java.util.List; public class Test2 { public static void main(String[] args) { Field f1 = new Field("tony", 11); Field f2 = new Field("jack", 11); Field f3 = new Field("tom", 11); Field f4 = new Field("jason", 44); List<Field> list = new ArrayList<Field>(); list.add(f1); list.add(f3); list.add(f4); list.add(f2); Collections.sort(list); for (Field o : list) { System.out.println(o.getAge() + "-->" + o.getName()); } } }