Java for Data Science

Using Java 8 streams

The release of Java 8 came with a number of important enhancements to the language. The two enhancements of interest to us include lambda expressions and streams. A lambda expression is essentially an anonymous function that adds a functional programming dimension to Java. The concept of streams, as introduced in Java 8, does not refer to IO streams. Instead, you can think of it as a sequence of objects that can be generated and manipulated using a fluent style of programming. This style will be demonstrated shortly.

As with most APIs, programmers must be careful to consider the actual execution performance of their code using realistic test cases and environments. If not used properly, streams may not actually provide performance ...