What are the correct data types for contours and moments?

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I have a running program for the Lego in C++. Now, I find out that LeJos for the Mindstorm EV3 only has an engine for Java for Eclipse. So, I need to convert my running C++ program to Java in Eclipse to have a link to the EV3. But, I am lost in the data structures. List, Array, Array-of-List, Mat, Array-of-Mat, Mat-of-Point, whatever... I have converted most of the code, but am stuck on the following...

Someone must know how to do this. THANK YOU

  //            vector<Moments> mu(  contours.size()  );                //  C++
   List<MatOfPoint> contours = new ArrayList<MatOfPoint>(); 
   ArrayList mu = new ArrayList<contours.size()>  ();
   Imgproc.cvtColor(dst, dst, Imgproc.COLOR_BGR2GRAY);
   Imgproc.threshold(dst, dst, 0, 255, Imgproc.THRESH_BINARY_INV | Imgproc.THRESH_OTSU);
   Imgproc.findContours(
     dst,                          //  Image              
     contours,                     //  Contours      
     hierarchy,                    //  Hierarchy                    
     Imgproc.RETR_TREE,     //int - Contour retrieval mode: RETR_LIST, RETR_CCOMP
     Imgproc.CHAIN_APPROX_NONE);//int -ContourapproximantionMethod:CHAIN_APPROX_SIMPLE, CHAIN_APPROX_NONE
    HighGui.imshow("After findContours.   Press any key ...", dst);
    HighGui.waitKey();
    int SumOfMoments = 0;
    int Mass = 0;

    for (int i = 0; i < contours.size(); i++)      //  From C++
    {                                              //  From C++
        mu[i] = moments(contours[i], false);       //  From C++
        SumOfMoments += mu[i].m10;                 //  From C++
        Mass += mu[i].m00;                         //  From  C++
    }