List<Object>使用Object的某个属性进行排序（正序，倒序）

package com.test;

public class User {
	private String name;
	private Integer orderNo;
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Integer getOrderNo() {
		return orderNo;
	}
	public void setOrderNo(Integer orderNo) {
		this.orderNo = orderNo;
	}
	
}

 

对List<User>进行排序：

 

package com.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) {
				User user1 =new User();
				user1.setName("c");
				user1.setOrderNo(3);
				User user2 =new User();
				
				user2.setName("c");
				user2.setOrderNo(1);
				User user3 =new User();
				user3.setName("b");
				user3.setOrderNo(2);
                List<User> list = new ArrayList<User>();
				list.add(user1);
				list.add(user2);
				list.add(user3);
				Collections.sort(list,new Comparator<User>(){
					public int compare(User arg0, User arg1){
						return arg1.getOrderNo().compareTo(arg0.getOrderNo());
					}
				});
				//倒序结果：
				/*c:3
				b:2
				c:1*/
				for(User u:list){
					System.out.println(u.getName()+":"+u.getOrderNo());
					
				}
				
				//正序结果
				/*c:1
				b:2
				c:3*/
				Collections.sort(list,new Comparator<User>(){
					public int compare(User arg0, User arg1){
						return arg0.getOrderNo().compareTo(arg1.getOrderNo());
					}
				});
				for(User u:list){
					System.out.println(u.getName()+":"+u.getOrderNo());
					
				}
	}

}

 

补充float型的属性比较，其他类型的属性也可以类似：

User three = new User();
		three.setMoney(0.9562F);
		three.setName("three");
		User four = new User();
		four.setMoney(1.12F);
		four.setName("four");
		List<User> userList = new ArrayList<>();
		userList.add(first);
		userList.add(two);
		userList.add(three);
		userList.add(four);
		/**
		 * 1倒序
		 */
		Collections.sort(userList,new Comparator<User>(){
			public int compare(User arg0, User arg1){
				 return arg1.getMoney()>= arg0.getMoney()? 1:-1;
			}
		});
		for(User u:userList){
			System.out.println(u);
		}
		
                /**
		 * -1正序
		 */
		Collections.sort(userList,new Comparator<User>(){
			public int compare(User arg0, User arg1){
				 return arg1.getMoney()>= arg0.getMoney()? -1:1;
			}
		});

注意：不同的jdk版本（jdk7以后貌似有点变化，这里的不能用>=符号），所以这样写：

/**
		 * 正序 jdk7以后建议使用
		 * Comparison method violates its general contract!
		 */
		Collections.sort(userList,new Comparator<User>(){
			public int compare(User arg0, User arg1){
				if(arg1.getMoney()>arg0.getMoney()){
					return -1;
				}else if(arg1.getMoney()== arg0.getMoney()){
					return 0;
				}else {
					return 1;
				}
				// return arg1.getMoney()>= arg0.getMoney()? -1:1;
			}
		});