JAVA

method reference in java

Java provides a feature called method
reference in Java 8. Method reference 
is used to refer method of functional interface.
  It is compact and easy form
  of lambda expression. Each time when 
  you are using lambda expression to just
  referring a method, you can replace your
  lambda expression with method reference.

Types of Method References:
- Reference to a static method.  Syntax ==> ContainingClass::staticMethodName  
- Reference to an instance method.  Syntax ==> containingObject::instanceMethodName  
- Reference to a constructor.  Syntax ==> ClassName::new  

method reference java

Sometimes, a lambda expression only calls an existing method. In those cases,
it looks clear to refer to the existing method by name. The method references 
can do this.