How to pass custom object between KNIME DataTable

Hi,

I am new to KNIME and I am developing some plugin for doing spatial operations in KNIME. I did not find any easy application to understand how to pass a custom object between KNIME Plugin. For example one of my plugin should generate a output table of Geometry objects. Which I can use the input port of my another Plugin. I am struggling to understand an easy way to map custom object ( e.g. Geometry) in DataCell.

 

Also how I can ontain the source code of some existing KNIME node easily. So, I can navigate directly from the node to view its source.

Thank you

Source code: https://tech.knime.org/forum/knime-developers/showing-source-code-of-existing-knime-nodes

Example Port Object:

For simple key-value type objects, look at org.knime.base.data.normalize.NormalizerPortObject (Geometry sounds as if a key-value map would suffice?)

Otherwise org.knime.base.node.preproc.correlation.pmcc.PMCCPortObjectAndSpec

Hope this helps,
  Bernd