方法一：实现Comparable接口排序package collsort.comparable; 

package com.cvicse.sort.comparable;

public class Cat implements Comparable<Cat> {

private int age;

private String name;

public Cat(int age, String name) {

this.age = age;

this.name = name;

}

public int getAge() {

return age;

}

public void setAge(int age) {

this.age = age;

}

......

public int compareTo(Cat o) {

return this.getAge() - o.getAge();

}

......

}

通过实现Comparable接口实现个性化排序测试。排序测试，Collection.sort(list)升序排列Collections.sort(list, Collections.reverseOrder());降序排列；Collections.reverse(list);反转排序，先输出列表最后一个元素

public class TestComparable {

public static void main(String args[]) {

test();

test2();

}

public static void test() {

......

List<Cat> listCat1 = new ArrayList<Cat>();

Cat cat1 = new Cat(34, "hehe");

Cat cat2 = new Cat(12, "haha");

Cat cat3 = new Cat(23, "leizhimin");

Cat cat4 = new Cat(13, "lavasoft");

listCat1.add(cat1);

listCat1.add(cat2);

listCat1.add(cat3);

......

System.out.println("调用Collections.sort(List<T> list)listCat2升序排序：");

Collections.sort(listCat1);

System.out.println("降序排列元素:");

Collections.sort(listCat1, Collections.reverseOrder());

System.out.println("Collections.reverse 从列表中最后一个元素开始输出:");

Collections.reverse(listCat1);

......

}

/**

* 针对数组的排序

*/

public static void test2() {

String[] strArray = new String[] { "z", "a", "C" };

System.out.println("数组转换为列表");

List<String> list = Arrays.asList(strArray);

System.out.println("顺序排序列表");

Collections.sort(list);

System.out

.println("按String实现的Comparator对象String.CASE_INSENSITIVE_ORDER排序----");

Collections.sort(list, String.CASE_INSENSITIVE_ORDER);

System.out.println("倒序排序列表");

Collections.sort(list, Collections.reverseOrder());

......

}

}

方法二：实现Comparator接口排序

public class Person {

private int age;

private String name;

......

public int getAge() {

return age;

}

public void setAge(int age) {

this.age = age;

}

......

}

实现了Comparator接口，重写了compare方法

import java.util.Comparator;

public class PersonComparator implements Comparator<Person> {

public int compare(Person o1, Person o2) {

return o1.getAge() - o2.getAge();

}

}

测试方法

public class TestComparator {

public static void main(String args[]) {

test1();

}

public static void test1() {

System.out.println("升序排序测试:");

List<Person> listPerson = new ArrayList<Person>();

Person person1 = new Person(34, "lavasoft");

Person person2 = new Person(12, "lavasoft");

Person person3 = new Person(23, "leizhimin");

Person person4 = new Person(13, "sdg");

listPerson.add(person1);

listPerson.add(person2);

listPerson.add(person3);

Comparator<Person> ascComparator = new PersonComparator();

System.out.println("排序后集合为:");

// 利用Collections类静态工具方法对集合List进行排序

Collections.sort(listPerson, ascComparator);

System.out.println("\n降序排序测试:");

// 从升序排序对象产生一个反转(降序)的排序对象

Comparator<Person> descComparator = Collections

.reverseOrder(ascComparator);

System.out.println("利用反转后的排序接口对象对集合List排序并输出:");

Collections.sort(listPerson, descComparator);

outCollection(listPerson);

}

}