List集合对象中的排序，随机显示

 List<User> students = new ArrayList<User>();  
         
         User user1 = new User();
         user1.setAge(112);
         user1.setUserName("小米");
         user1.setMoney(118.55);
         students.add(user1);  
         
         User user2 = new User();
         user2.setAge(82);
         user2.setUserName("小王");
         user2.setMoney(88.55);
         students.add(user2); 
         
         User user3 = new User();
         user3.setAge(100);
         user3.setUserName("小李");
         user3.setMoney(110.65);
         students.add(user3); 
         
         User user4 = new User();
         user4.setAge(99);
         user4.setUserName("小赵");
         user4.setMoney(99.5);
         students.add(user4); 
              
            Collections.sort(students, new Comparator<User>() {  
                  @Override
                public int compare(User o1, User o2) {
                      //降序
                      /*if(o1.getMoney()>o2.getMoney()){
                          return -1;
                      }
                      if(o1.getMoney()<o2.getMoney()){
                          return 1;
                      }
                      return 0;*/
                          
                      //升序
                          if(o1.getMoney()>o2.getMoney()){
                              return 1;
                          }
                          if(o1.getMoney()<o2.getMoney()){
                              return -1;
                          }
                          return 0;
                      
                     /*int i = o1.getAge() - o2.getAge();  
                     return i;*/
                }  
            });  
            for(User stu : students){  
                System.out.println("score:" + stu.getUserName() + ":age:" + stu.getAge()+":money:"+stu.getMoney());  
            }  

简单类型list排序

List<Integer> nums = new ArrayList<Integer>();  
        nums.add(3);  
        nums.add(5);  
        nums.add(1);  
        nums.add(0);  
        System.out.println(nums);  
        Collections.sort(nums);  
        System.out.println(nums);

 list集合随机显示（实体类）

 List<Integer> list = new ArrayList<Integer>();
            for (int i = 0; i < 5; i++) {
                list.add(i);
            }
            Collections.shuffle(list);
            for(Integer yy:list){
                 System.out.println("随机："+yy);
            }