Extract Params from metadata, and set them in the instance.
The params included in
skipParams won't be set. This is useful if some
params don't implement org.apache.spark.ml.param.Param.jsonDecode()
and need special handling.
Helper for OpPipelineStageWriter which extracts the JSON to save.
OpPipelineStageWriter for details on what this includes.
Parse metadata JSON string produced by DefaultParamsWriter.getMetadataToSave().
JSON string of metadata
If non empty, this is checked against the loaded metadata.
IllegalArgumentException if expectedClassName is specified and does not match metadata