java利用反射扩展任意数组的方法

package com.company;
import java.lang.reflect.Array;
import java.util.Arrays;
/**
 * java利用反射扩展任意数组的方法
 */
public class TestReflect {
    public static void main(String[] args) {
        int[] arr = {1,2,3,4,5};
        int[] o = (int[]) exprendArrayLength(arr, 8);
        System.out.println(Arrays.toString(o));
    }
    public static Object exprendArrayLength(Object a, int newLength){
        Class<?> aClass = a.getClass();
        if(!aClass.isArray()){
            return  null;
        }
        Class<?> componentType = aClass.getComponentType();
        int length = Array.getLength(a);
        Object newArray = Array.newInstance(componentType, newLength);
        System.arraycopy(a,0,newArray,0,Math.min(length,newLength));
        return newArray;
    }
}