JDK1.8对List指定字段进行排序

import java.util.ArrayList;

import java.util.Collections;

import java.util.Comparator;

import java.util.List;

import com.wubei.demo.bean.Order;

public class ListStreamTest {

public static void main(String[] args) {

List<Order> orderList = new ArrayList<Order>();

orderList.add(order);

orderList.add(order1);

orderList.add(order2);

orderList.add(order3);

orderList.add(order4);

//1.jdk8 lambda排序，带参数类型

orderList.sort(( Order ord1, Order ord2) -> ord2.getOrderId().compareTo(ord1.getOrderId()));

//2.jdk8 lambda排序，不带参数类型

orderList.sort(( ord1, ord2) -> ord2.getOrderId().compareTo(ord1.getOrderId()));

//3.jdk8 升序排序，Comparator提供的静态方法

Collections.sort(orderList, Comparator.comparing(Order::getOrderId));

//4.jdk8 降序排序，Comparator提供的静态方法

Collections.sort(orderList, Comparator.comparing(Order::getOrderId).reversed());

//5.jdk8 组合排序，Comparator提供的静态方法，先按orderId排序，orderId相同的按userId排序

Collections.sort(orderList, Comparator.comparing(Order::getOrderId).reversed().thenComparing(Order::getUserId));

orderList.stream().forEach(str -> System.out.println(str.getOrderId()+"/" + str.getUserId()));

//6 jdk8对List<Map<String,Object>> data进行排序

Collections.sort(data , (o1, o2) -> o2.get("approval_time").toString().compareTo(o1.get("approval_time").toString()));

}

}