arraycopy效率比较

import java.util.Date;public class TestArrayCopy {public static void main(String[] args) {Date d1 = new Date();int[] arr = new int[10000000];for(int i = 0; i < 10000000; i++) {arr[i] = i;}Date d2 = new Date();System.out.println(d2.getTime() - d1.getTime());int[] arr2 = new int[10000000];Date d3 = new Date();System.arraycopy(arr,0, arr2, 0, 10000000);Date d4 = new Date();System.out.println(d4.getTime() - d3.getTime());}}