What is the purpose of a static method in interface from Java 8?

Question

Why are static methods supported from Java 8? What is the difference between the two lines in main method in below code?

package sample;
public class A {
    pub         


        

Answer 1

There are mainly two reasons for static method inside interfaces: create instances of those interfaces (and the code is clearly where it has to be); like Predicate::isEqual that would create a Predicate based provided Object; or Comparator::comparing, etc. And the second reason would be utility methods that are general per all those types; like Stream::of

Still an interface has to be clear and does not have to create additional clutter in the API. Even the jdk code has Collectors - static factory methods, but a Collector interface at the same time for example. Those methods could be merged into Collector interface, but that would make the interface more clunky than it has to be.