code: public static Matrix getRotationJAMA(Matrix4d transform) {
  
  		Matrix rot = new Matrix(3, 3);
  		for (int i = 0; i < 3; i++) {
  			for (int j = 0; j < 3; j++) {
  				rot.set(j, i, transform.getElement(i, j)); // transposed
  			}
  		}
  		return rot;
  	}
docs: Convert a transformation matrix into a JAMA rotation matrix. Because the
  JAMA matrix is a pre-multiplication matrix and the Vecmath matrix is a
  post-multiplication one, the rotation matrix is transposed to ensure that
  the transformation they produce is the same.
  
  @param transform
  Matrix4d with transposed rotation matrix
  @return rotation matrix as JAMA object