public class Test2 { public static void main(String[] args) { int [] its = {1,2,3}; int [] it2 = {4,5,6}; its = Arrays.copyOf(its, its.length+it2.length); //该操作只是将原来数组容量变大了,并没有进行复制 //复制的话,只能使用System.arrayCopy()进行 System.out.println(its.length); } }