Arrays类操作数组的方法

package com.web;

import java.util.Arrays;

public class Test7 {
    
    
    public static void main(String[] args) {
    
    
        int[] arr = {
    
    2, 4, 1, 9, 2, 7};
        // 打印数组,输出地址值
        System.out.println("arr = " + arr);
        //arr = [I@5e2de80c
        // 数组内容转为字符串 ，排序前
        System.out.println(Arrays.toString(arr));//[2, 4, 1, 9, 2, 7]
        // 升序排序
        Arrays.sort(arr);
        //排序后
        System.out.println(Arrays.toString(arr));//[1, 2, 2, 4, 7, 9]

        // 反向遍历打印
        //必须i>=0,若i>0,则少输出一个arr[0] = 1
        for (int i = arr.length - 1; i >= 0; i--) {
    
    
            System.out.println("arr[" + i + "] = " + arr[i]);
        }
                /*
          arr[5] = 9
          arr[4] = 7
          arr[3] = 4
          arr[2] = 2
          arr[1] = 2
          arr[0] = 1
        */

        // 定义随机的字符串
        String line = "ysKUreaytWTRHsgFdSAoidq";
        char[] chars = line.toCharArray();
        // 升序排序
        Arrays.sort(chars);
        //错误示范
        System.out.println("chars = " + chars.toString());//chars = [C@1d44bcfa
        //正确示范
        System.out.println("chars = " + Arrays.toString(chars));//chars = [A, F, H, K, R, S, T, U, W, a, d, d, e, g, i, o, q, r, s, s, t, y, y]
        // 反向遍历打印不要写成了int i = chars.length
        for (int i = chars.length - 1; i >= 0; i--) {
    
    
            if (i==chars.length-1){
    
    
                System.out.print("chars = "+chars[i]+" ");
                //不加contine，多输出一个y
                //continue:结束本次循环，继续下一次循环
                //break:终止switch或者循环
                continue;
            }
            System.out.print(chars[i] + " ");
        }//chars = y y t s s r q o i g e d d a W U T S R K H F A
    }

}