implement Serializable for ThresholdedRandomCutForestState

[ylwu-amzn]

Signed-off-by: Yaliang Wu ylwu@amazon.com

#297

Description of changes:
implement Serializable for ThresholdedRandomCutForestState

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[jotok]

Per the recommendation in the Javadocs for Serializable, we should explicitly define the serialVersionUID constant to the classes that implement Serializable.
https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/io/Serializable.html

[jotok]

Can we create an example based on the existing serialization examples that serializes and deserializes a forest and validates that the deserialized forest produces outputs that are consistent with the original forest?
https://github.com/aws/random-cut-forest-by-aws/blob/main/Java/examples/src/main/java/com/amazon/randomcutforest/examples/serialization/ProtostuffExample.java

[ylwu-amzn]

Per the recommendation in the Javadocs for Serializable, we should explicitly define the serialVersionUID constant to the classes that implement Serializable. https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/io/Serializable.html

Thanks, will add. BTW, will evaluate other serialization lib later and may change the serialization way in MLCommons. Currently use ObjectOutputStream is mainly to keep consistent with current code and save effort to unblock some work.

[ylwu-amzn]

existing serialization examples that serializes and deserializes a forest and validates that the deserialized forest produces outputs that are consistent wi

Sure, will add

[ylwu-amzn]

Can anyone help take a look and approve if no more comments? @jotok @sudiptoguha

[ylwu-amzn]

Ran ObjectStreamExample on Mac successfully.

dimensions = 10, numberOfTrees = 50, sampleSize = 256, precision = FLOAT_32
Object output stream size = 326809 bytes
Looks good!