New features in Java 8

Java 8, released on March 8, 2014, brought arguably two of the most significant features since Java 5, released in 2004--lambdas and streams. With functional programming gaining popularity in the JVM world, especially with the help of languages such as Scala, Java adherents had been clamoring for more functional-style language features for several years. Originally slated for release in Java 7, the feature was dropped from that release, finally seeing a stable release with Java 8.

While it can be hoped that everyone is familiar with Java's lambda support, experience has shown that many shops, for a variety of reasons, are slow to adopt new language versions and features, so a quick introduction might be helpful.

Lambdas

The term lambda, which has its roots in lambda calculus, developed by Alonzo Church in 1936, simply refers to an anonymous function. Typically, a function (or method, in more proper Java parlance), is a statically-named artifact in the Java source:

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