Static methods added in interfaces in java 1.8

Question

As we know that in java 1.8 static methods are allowed in interfaces , I have seen some answers like static methods defined in interface from jdk 1 8 why did they need to do so
but I am not satisfied.
Furthermore I think it may cause problems like :

 public interface MyInterface{
      public static void myMethod();
    }

  class MyClass{
    MyInterface.myMethod();  // since myMethod is static but a huge error is waiting for us here ?
  }

But I still think there is a way out of this since this is added by professionals , so can anyone please explain how oracle solves this issue and what is the need to add this ?
Thank you in adavance.

I have not used java 1.8 so I never knew that static methods in java needs to be defined not just declared , I always thought of the Interfaces as a Pure Abstract Class I think that's why the idea of defining a method seemed strange to me . Thank you for your help ! .

I don't have much experience in 1.8, but `public static void myMethod();` got to be a syntax error. Static methods must be defined, not just declared. — , Sep 19 '14 at 12:47
"abstract" means: "Implements no functionality", and "static" means: "There is functionality even if you don't have an object instance". And that's a logical contradiction. You can't have an `abstract static` method. — Narmer, Sep 19 '14 at 13:00
@Narmer That is why I thought Interfaces shouldn't have static methods — user3921830, Sep 19 '14 at 13:02
You can have a static method in an interface (as per Java 8) as long as you implement it in the interface. — Narmer, Sep 19 '14 at 13:02

Abhiroop Sarkar · Accepted Answer · 2014-09-19T12:56:30.973

Talking about "what is the need to add" static methods:

Quoting from http://www.informit.com/articles/article.aspx?p=2191423

Before Java 8 made it possible to declare static methods in interfaces, it was common practice to place these methods in companion utility classes. For example, the java.util.Collections class is a companion to the java.util.Collection interface, and declares static methods that would be more appropriate in the relevant Java Collections Framework interfaces. You no longer need to provide your own companion utility classes. Instead, you can place static methods in the appropriate interfaces, which is a good habit to cultivate.

Also static methods in interfaces are good for providing utility methods like null check, collection sorting etc. And importantly it provides security by denying implementation classes from overriding it.

Thank you ! understood the concept – user3921830 Sep 19 '14 at 13:05 — user3921830, Sep 19 '14 at 13:05

score 0 · Answer 2 · answered Sep 19 '14 at 12:45

0

There's no problem here, the static method is owned by class, not it's members, so the only error here is the fact you didn't defined the method itselt (just declared it, which is not allowed with static methods).

answered Sep 19 '14 at 12:45

Dmitry Ginzburg

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Static methods added in interfaces in java 1.8

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