[List Exercise] Traverse the collection and sort by price from low to high,

package com.zhang.list_;import java.util.ArrayList;import java.util.List;public class ListTestBook {public static void main(String[] args) {List list = new ArrayList();list.add(new Books("Three Kingdoms",200));list.add(new Books("Journey to the West",81));list.add(new Books("Water Margin",108));for (Object o :list) {System.out.println(o);}System.out.println("======After sorting========");sort(list);for (Object o :list) {System.out.println(o);}}public static void sort(List list){for (int i = 0;i < list.size()-1;i++){for (int j = 0;j < list.size()-1-i;j++){//Take out the object Book and downcastBooks book1 = (Books) list.get(j);Books book2 = (Books) list.get(j+1);if (book2.getPrice() < book1.getPrice()){list.set(j,book2);list.set(j+1,book1);}}}}}class Books{public Books() {}@Overridepublic String toString() {return "name:"+name+",price:"+price;}private String name;private int price;public Books(String name, int price) {this.name = name;this.price = price;}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getPrice() {return price;}public void setPrice(int price) {this.price = price;}}