What is the Library available for the construction of each Pipeline Steps?
The following article show how you can use H2O to import data, perform some data munging such as join tables etc and perform the machine learning on given data frame. You will learn to build GBM model first and perform prediction. You will also learn to perform grid search with hyperparameters and then get the leader model. Overall it is a complete Scala example to perform machine learning with H2O in Scala.
This article shows how you can use H2O POJO and MOJO models to perform scoring in Scala: