Functional Programming in Java, 2nd Edition

Wrapping Up

Efficiency got a boost in Java with the introduction of lambdas; we can be lazy and postpone the execution of code until we need it. We can delay the initialization of heavyweight resources and easily implement the virtual proxy pattern. Likewise, we can delay the evaluation of method arguments to make the calls more efficient. The real heroes of the improved JDK are the Stream interface and the related classes. We can exploit their lazy behaviors to create infinite collections with just a few lines of code. That means highly expressive, concise code to perform complex operations that we couldn’t even imagine in Java before.

In the next chapter we’ll look at the roles lambda expressions play in optimizing recursions.

Footnotes