List 对象排序 Demo

List 对象排序 Demo

 

项目目录结构：

 
简单POJO   Person.java

package com.royal.model;

public class Person {
	
	private String name;
	
	private int age;
	
	public Person(){
		
	}
	
	public Person (String name, int age){
		this.name = name;
		this.age = age;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public int getAge() {
		return age;
	}

	public void setAge(int age) {
		this.age = age;
	}

}

 

 

一个List对象排序的工具类

SortList.java

package com.royal.util;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

/**
 * 
 * @Description: TODO(List排序工具类) 
 *
 */
public class SortList<E> {

	public void sort(List<E> list, final String method, final String sort) {
		Collections.sort(list, new Comparator() {

			@Override
			public int compare(Object a, Object b) {
				int ret = 0;
				try {
					Method m1 = ((E) a).getClass().getMethod(method, null);
					Method m2 = ((E) b).getClass().getMethod(method, null);

					if (sort != null && "desc".equals(sort)) {
						// 倒序
						ret = m2.invoke(((E) b), null).toString().compareTo(m1.invoke(((E) a), null).toString());
					} else {
						// 正序
						ret = m1.invoke(((E) a), null).toString().compareTo(m2.invoke(((E) b), null).toString());
					}
				} catch (SecurityException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				} catch (NoSuchMethodException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				} catch (IllegalArgumentException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				} catch (IllegalAccessException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				} catch (InvocationTargetException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}

				return ret;
			}
		});
	}

}

 

工具类的测试使用

SortListClient.java

package com.royal.test;

import java.util.ArrayList;
import java.util.List;

import com.royal.model.Person;
import com.royal.util.SortList;

public class SortListClient {
	
	public static void main(String[] args){
		Person p1 = new Person("royal",18);
		Person p2 = new Person("萧_瑟",20);
		
		List<Person> personList = new ArrayList<Person>();
		personList.add(p1);
		personList.add(p2);
		
		SortList<Person> sortList = new SortList<Person>();
		
		System.out.println("-----原来的序列-----");
		for(Person p : personList){
			System.out.println(p.getName() + "\t" + p.getAge());
		}
		
		System.out.println("-----按age正序排序-----");
		sortList.sort(personList, "getAge", null);
		for(Person p : personList){
			System.out.println(p.getName() + "\t" + p.getAge());
		}
		
		System.out.println("-----按age倒序排序-----");
		sortList.sort(personList, "getAge", "desc");
		for(Person p : personList){
			System.out.println(p.getName() + "\t" + p.getAge());
		}
	}

}

 

 

测试结果：

 

参考：http://wenku.baidu.com/view/a19a50ea81c758f5f61f674a.html