自然排序Comparable
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对于自定义类进行排序要实现Comparable接口，重写compareTo() 方法,如果不重写，像使用Arrays.sort()排序就会报错

package com.che.lambda; import java.util.Objects; /** * @author cheyuhang on 2021/4/23 */public class Goodimplements Comparable{private String name; private Double price; public Good(String name, Double price) {this.name = name; this.price = price; }public Good() {}public String getName() {return name; }public void setName(String name) {this.name = name; }public Double getPrice() {return price; }public void setPrice(Double price) {this.price = price; }@Overridepublic boolean equals(Object o) {if (this == o) return true; if (o == null || getClass() != o.getClass()) return false; Good good = (Good) o; return Objects.equals(name, good.name) && Objects.equals(price, good.price); }@Overridepublic int hashCode() {return Objects.hash(name, price); }@Overridepublic String toString() {return "Good{" +"name='" + name + '\'' +", price=" + price +'}'; }@Overridepublic int compareTo(Object o) {if (o instanceof Good){//判断传递参数是否属于商品Good good=(Good) o; if(this.price >good.price){return 1; }else if(this.price
定制排序Comparator 【Java基础之Comparable与Comparator概述】使用场景：当类没有实现Comparable接口或者实现了Comparable接口，但不符合我期望的排序规则时进行使用

@Testpublic void test02() {Good[] arr=new Good[5]; arr[0] =new Good("zhangsan",234.0); arr[1] =new Good("lisi",2343.0); arr[2] =new Good("wangwu",2354.0); arr[3] =new Good("zhaoliu",2334.0); arr[4] =new Good("tianqi",2347.0); System.out.println(Arrays.toString(arr)); Arrays.sort(arr, new Comparator