Lambdas have been the biggest change in the language since generics were introduced in Java 5. This was a fundamental change that impacted many of the APIs to follow. Anonymous classes are very useful to pass code around, but they come at the cost of readability as they lead to some boilerplate code (think Runnable or ActionListener). Those wanting to write clean code that is readable and void of any boilerplate would appreciate what lambda expressions have to offer.
In general, lambda expressions can only be used where they will be assigned to a variable whose type is a functional interface. The arrow token (->) is called the lambda operator. A functional interface is simply an interface having exactly ...
