Android-OpenCV camera orientation issue

First I get into JavaCameraView.java class in the OpenCV Library

and then in the initializeCamera add the following lines just before mCamera.startPreview();

            setDisplayOrientation(mCamera, 90);

            mCamera.setPreviewDisplay(getHolder());

The first function implemented like this

protected void setDisplayOrientation(Camera camera, int angle){

    Method downPolymorphic;

    try

    {

        downPolymorphic = camera.getClass().getMethod("setDisplayOrientation", new Class[] { int.class });

        if (downPolymorphic != null)

            downPolymorphic.invoke(camera, new Object[] { angle });

    }

    catch (Exception e1)

    {

        e1.printStackTrace();

    }

} 

Reference : https://stackoverflow.com/questions/16669779/opencv-camera-orientation-issue