[java]数组复制的2种方式

package org.company.project.test;
import java.util.Arrays;
import java.util.Random;
import java.util.Scanner;
public class ArraysCopy {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("随机数组请输入长度：");
int n = sc.nextInt();
sc.close();

int[] arr = new int
;
Random ra = new Random();
for(int i=0;i
arr[i] = ra.nextInt(100);
}
System.out.println("arr:\n"+Arrays.toString(arr));

int[] arr1 = new int[n+1];
System.arraycopy(arr, 0, arr1, 0, arr.length);
System.out.println("arr扩容1个长度赋值给arr1：\n"+Arrays.toString(arr1));

arr = Arrays.copyOf(arr, n+2);
System.out.println("arr本身扩容2个长度：\n"+Arrays.toString(arr));
}
}