vtkPlanes not making planes

Development
#1

I’m attempting to make a vtkPlanes object with the following Java code:

vtkPlanes planes = new vtkPlanes();
planes.SetPoints(planePoints);
planes.SetNormals(planeNormals);

Where planePoints is a vtkPoints object and planeNormals is a vtkDataArray. When I call planes.GetNumberOfPlanes(), it always returns 0. What am I missing? Is there something I need to do to make it forms the planes? As usual the documentation is less than informative. Thanks for any information you can provide.

#2

Not quite sure about the Java implementation of vtk, but typically in C++ I need to call a update function to make sure the output is as configured.
Does

planes.update();

exist, or work?

#3

I think I figured it out - for some reason vtkDataArray is initializable when it really shouldn’t be - you have to use something like vtkDoubleArray or vtkFloatArray