java的arraylist排序示例(arraylist用法)

写了一个java数组排序示例，这里分享给大家共同学习

package com.yonyou.test;
import java.util.arraylist;
import java.util.collections;
import java.util.comparator;
import java.util.list;
public class test {
 public static void main(string[] args) {
  student zlj = new student("丁晓宇", 21);
  student dxy = new student("赵四", 22);
  student cjc = new student("张三", 11);
  student lgc = new student("刘武", 19);
  list<student> studentlist = new arraylist<student>();
  studentlist.add(zlj);
  studentlist.add(dxy);
  studentlist.add(cjc);
  studentlist.add(lgc);
  system.out.println("按照年齡排序：");
  collections.sort(studentlist, new sortbyage());
  for (student student : studentlist) {
   system.out.println(student.getname() + " / " + student.getage());
  }
  system.out.println(" ========= ");
  system.out.println("按照姓名排序");
  collections.sort(studentlist, new sortbyname());
  for (student student : studentlist) {
   system.out.println(student.getname() + " / " + student.getage());
  }
 }
}
class sortbyage implements comparator {
 public int compare(object o1, object o2) {
  student s1 = (student) o1;
  student s2 = (student) o2;
  if (s1.getage() > s2.getage())
   return 1;
  else if (s1.getage() == s2.getage()) {
   return 0;
  }
  return -1;
 }
}
class sortbyname implements comparator {
 public int compare(object o1, object o2) {
  student s1 = (student) o1;
  student s2 = (student) o2;
  if(s1.getname().compareto(s2.getname()) < 0)
   return -1;
  else if (s1.getname().compareto(s2.getname()) > 0) {
   return 1;
  }
  return 0;
 }
}
class student{
 private int age;
 private string name;
 public int getage() {
  return age;
 }
 public void setage(int age) {
  this.age = age;
 }
 public string getname() {
  return name;
 }
 public void setname(string name) {
  this.name = name;
 }
 public student(string name,int age) {
  this.age = age;
  this.name = name;
 }
}