I discover H2O thanks to the R community where I found a post about the connection of this tool with R. Besides the interest for Machine Learning and Statistics (Data Science) which has been increasing during this year (yes, I did not do anything with it: but I need to learn before, and I take years to do it ;-( ), I was intrigued by the fact that it is implemented in Java, is said to be fast, has connection to R, Scala and Python, and has among the advisors Joshua Bloch, so, I guess, it should be REALLY good Java from which to learn. Obviously I did add it to my previous overviews of Java and R tools for hydrologists.
If they are really good as they promised, there are several things that we can copy from them: the connection to R, their class to read data, their strategies for doing math.
The tool is open source, information and download can be found at H2O site. During the H2O conference, the famous statisticians Trevor Hastie and John Chambers gave interesting talks that can be found here.