import java.lang.reflect.Array;
public class Main {
public static void main(String[] argv) throws Exception {
int[] array = { 1, 2, 3 };
Object newArray = Array.newInstance(array.getClass().getComponentType(),
Array.getLength(array) * 2);
System.arraycopy(array, 0, newArray, 0, Array.getLength(array));
}
}