Skip to main content

Posts

Showing posts with the label method expressions

Java 8 - Method references

This article is in continuation to my other posts on Functional Interfaces , static and default methods and Lambda expressions . Method references are the special form of Lambda expression . When your lambda expression are doing nothing other than invoking existing behaviour (method), you can achieve same by referring it by name. :: is used to refer to a method. Method type arguments are infered by JRE at runtime from context it is defined. Types of method references Static method reference Instance method reference of particular object Instance method reference of an arbitrary object of particular type Constructor reference Static method reference When you refer static method of Containing class. e.g. ClassName::someStaticMethodName class MethodReferenceExample { public static int compareByAge(Employee first, Employee second) { return Integer.compare(first.age, second.age); } } Comparator compareByAge = MethodReferenceExample::compareByAge; Instanc