比较器Comparator与自定义排序

package com.yin2na.example;import java.util.List;import java.util.ArrayList;import java.util.Collections;import java.util.Comparator;public class SortTest {public static void main(String[] args) {List<Student> list = new ArrayList<Student>();list.add(new Student("yin2na", 24));list.add(new Student("susanbear", 22));list.add(new Student("doing", 20));list.add(new Student("Jesus", 2011));System.out.println("原顺序：");for(Student stu : list){System.out.println(stu);}System.out.println("默认顺序：");Collections.sort(list);for(Student stu : list){System.out.println(stu);}System.out.println("反序：");Collections.sort(list, Collections.reverseOrder());//Collections.reverseOrder()返回一个比较器Comparatorfor(Student stu : list){System.out.println(stu);}System.out.println("自定义顺序：");Collections.sort(list, new Comparator<Student>(){//匿名内部类public int compare(Student stu1, Student stu2){if (stu1.getName().length() > stu2.getName().length()){return 1;}else if (stu1.getName().length() < stu2.getName().length()){return -1;}else{return 0;}}});for(Student stu : list){System.out.println(stu);}}}class Student implements Comparable<Student>{private String name;private int age;public Student(String name, int age){this.name = name;this.age = age;}public String getName(){return name;}public int compareTo(Student stu){if (this.age > stu.age){return 1;}else if (this.age < stu.age){return -1;}else{return 0;}}@Overridepublic String toString(){return name + " is " + age;}}