Functional Programming in Java

Delegating Using Lambda Expressions

We used lambda expressions and the strategy pattern to separate a concern from a method. We can also use them to separate a concern from a class. From a reuse point of view, delegation is a better design tool than inheritance. With delegation it’s easier to vary the implementation we rely on, and we can plug in a different behavior more dynamically. This can help vary the behavior of classes independent of the behavior of the parts they depend on, and make the design more flexible without forcing a deep class hierarchy.

Creating a Delegate

Rather than delegating part of the responsibility to another class, we can delegate it to lambda expressions and method references. This will further reduce class proliferation. ...