Comparable接口的实现：

今天项目用到进行金额排序，之前学过的java基础有点忘记，补充一下

没有实现Comparable接口时，取出来的值无法排序

public static void main(String[] args) {Good1[] arr1 = new Good1[5];arr1[0] = new Good1("大哥",10.0);arr1[1] = new Good1("二弟",40.0);arr1[2] = new Good1("三弟",200.0);arr1[3] = new Good1("四弟",900.0);arr1[4] = new Good1("五弟",60.0);System.out.println("====没有实现实现Comparab接口时输出====");System.out.println(Arrays.asList(arr1));}

运行得到的结果：

如果进行排序：

Good1[] arr1 = new Good1[5];arr1[0] = new Good1("大哥",10.0);arr1[1] = new Good1("二弟",40.0);arr1[2] = new Good1("三弟",200.0);arr1[3] = new Good1("四弟",900.0);arr1[4] = new Good1("五弟",60.0);Arrays.sort(arr1);System.out.println("====没有实现实现Comparab接口时输出====");System.out.println(Arrays.asList(arr1));

报错

实现接口进行排序：

Controller层的实现

public static void main(String[] args) {Good[] arr = new Good[5];arr[0] = new Good("大哥",10.0);arr[1] = new Good("二弟",40.0);arr[2] = new Good("三弟",200.0);arr[3] = new Good("四弟",900.0);arr[4] = new Good("五弟",60.0);Arrays.sort(arr);System.out.println("====实现Comparab接口时输出====");System.out.println(Arrays.asList(arr));}

实体类的实现

@Data
public class Good implements Comparable<Good>{private String name;private Double price;public Good(String name, Double price) {this.name = name;this.price = price;}//重写比较方法
//如果当前对象大于形参对象，返回1
//如果当前对象小于形参对象。返回-1
//如果相等，返回0@Overridepublic int compareTo(Good o) {if (this.price>o.price)return 1;else if (this.price<o.price)return -1;elsereturn 0;}
}

成功实现：

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复习时间：

2023/08/12