Question

OK so what if i have a method like:

Object[] myTest(int[] a, double[] b){
   return new Object[]{a,b};
}

Now How can i cast the result Object to int[] and double[]?

Like if i use:

int[] array1 = (int[]) myTest(a,b)[0];
double[] array2 = (double[]) myTest(a,b)[1];

But this does not work. Or is there any efficient method to do this job?

Answer 1

Not sure why you’re having difficulty: on Java 6 this works as expected.

Try compiling this class and running it:

public class t1
{
    public static void main(String[] args) throws Exception
    {
    int[] a = new int[1];
    double[] b = new double[1];

    int[] array1 = (int[]) myTest(a,b)[0];
    double[] array2 = (double[]) myTest(a,b)[1];
    System.err.println(array1);
    System.err.println(array2);
    }

    static Object[] myTest(int[] a, double[] b){
    return new Object[]{a,b};
    }
}

it will print out

[I@3e25a5
[D@19821f

That’s the autoboxing taking place, but will still work.