java day07 初识Arrays工具类

package helloworld;

import java.util.Arrays;

import java.util.Scanner;

/**
 * 、
 * @Description
 * @author 
 * @date 2020年7月25日上午9:42:23
 */
public class HelloWorld {
    public static void main(String[] args) {
    	//1.boolean equals(int[] a, int[] b);判断两个数组是否相等
       int[] arr1 = new int[] {1,2,3,4};
       int[] arr2 = new int[] {1,3,2,4};
       boolean isEuqals = Arrays.equals(arr1, arr2);
       System.out.println(isEuqals);
       
       //2.String toString(int[] a);输出数组信息
       System.out.println(Arrays.toString(arr1));
       
       //3.void fill(int[] a,int val);将指定值填充到数组中去
       Arrays.fill(arr1, 10);
       System.out.println(Arrays.toString(arr1));
       
       //4.void sort(int[] a);对数组进行排序
       Arrays.sort(arr2);
       System.out.println(Arrays.toString(arr2));
       
       //5.int binarySearch(int[] a,int key);
       int[] arr3  = new int[] {3,23,2,4,5};
       int index = Arrays.binarySearch(arr3, 210);
       if(index >= 0) {
    	   System.out.println(index);
       }else {
    	   System.out.println("未找到！");
       }
    }
}