一.通过Comparable 接口，实现自然排序

import java.lang.reflect.Array;
import java.util.Arrays;


public class ComparableTest {
    public static void main(String[] args) {
        // 重写Comparable接口的规则
        String [] arr = new String[]{"BB","ff","de","AA"};
        Arrays.sort(arr);
        System.out.println(Arrays.toString(arr));
        //
        Goods[] goods = new Goods[4];
        goods[0] = new Goods("huaweimouse",45.9);
        goods[1] = new Goods("lemouse",45.1);
        goods[2] = new Goods("xiaomimouse",48.9);
        goods[3] = new Goods("luojimouse",100.5);
        Arrays.sort(goods);
        System.out.println(Arrays.toString(goods));
    }

}
// 1.实现Comparable接口类
class Goods implements Comparable {
    private  String name;
    private  Double price;
    public Goods(String name,Double price){
        this.name =name;
        this.price =price;
    }

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

    public void setPrice(Double price) {
        this.price = price;
    }

    public String getName() {
        return name;
    }

    public Double getPrice() {
        return price;
    }
    public String toString(){
        return "Goods"+"["+this.name+","+this.price+"]";
    }
    // 2.重写compareTo 方法，指明商品比较大小的方法
    @Override
    public int compareTo(Object o) {
        if (o instanceof Goods ){
            Goods goods = (Goods)o;
            if (this.pricegoods.price){
                return 1;
            }else{
                return 0;
            }
//            // 方式二
//            return Double.compare(this.price,goods.price);
        }else{
            throw new RuntimeException("传入的数据类型不一致！");
        }
    }
}

二.通过Comparator接口，实现定制排序

import java.lang.reflect.Array;
import java.util.Arrays;
import java.util.Comparator;

import org.junit.Test;

public class ComparableTest {
    public static void main(String[] args) {
        // 重写Comparable接口的规则
//        String[] arr = new String[]{"BB", "ff", "de", "AA"};
        String [] arr = new String[]{"BB","FF","DD","AA"};
//        Arrays.sort(arr);
//        System.out.println(Arrays.toString(arr));
        //
        Goods[] goods = new Goods[4];
        goods[0] = new Goods("huaweimouse", 45.9);
        goods[1] = new Goods("lemouse", 45.1);
        goods[2] = new Goods("xiaomimouse", 48.9);
        goods[3] = new Goods("luojimouse", 100.5);
//        Arrays.sort(goods);
//        System.out.println(Arrays.toString(goods));

    }
    @Test
    public void testGood(){

        Goods[] goods = new Goods[4];
        goods[0] = new Goods("huaweimouse", 45.9);
        goods[1] = new Goods("lemouse", 45.1);
        goods[2] = new Goods("xiaomimouse", 48.9);
        goods[3] = new Goods("luojimouse", 100.5);
        Arrays.sort(goods,new Comparator(){
            @Override
            public int compare(Object o1, Object o2) {
                if (o1 instanceof Goods && o2 instanceof Goods){
                    Goods s1 =(Goods)o1;
                    Goods s2 =(Goods)o2;
//                    return Double.compare(s1.getPrice(),s2.getPrice());// 从小到大排
                    return -Double.compare(s1.getPrice(),s2.getPrice());// 从大到小排
//
                }else{
                    throw new RuntimeException("输入的数据类型有误");

                }
            }
        });

        System.out.println(Arrays.toString(goods));
    }
}


class TestComparator{

}
// 1.实现Comparable接口类
class Goods implements Comparable {
    private  String name;
    private  Double price;
    public Goods(String name,Double price){
        this.name =name;
        this.price =price;
    }

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

    public void setPrice(Double price) {
        this.price = price;
    }

    public String getName() {
        return name;
    }

    public Double getPrice() {
        return price;
    }
    public String toString(){
        return "Goods"+"["+this.name+","+this.price+"]";
    }
    // 2.重写compareTo 方法，指明商品比较大小的方法
    @Override
    public int compareTo(Object o) {
        if (o instanceof Goods ){
            Goods goods = (Goods)o;
            if (this.pricegoods.price){
                return 1;
            }else{
                return 0;
            }
//            // 方式二
//            return Double.compare(this.price,goods.price);
        }else{
            throw new RuntimeException("传入的数据类型不一致！");
        }
    }
}