InputModifierClassesInsideOfInterfaces.java

package com.puppycrawl.tools.checkstyle.checks.modifier;

public interface InputModifierClassesInsideOfInterfaces {

    // Class inside of interface can be abstract and non abstract, but always public static.
    abstract class A {}

    class B {}

    // All classes inside interfaces are public static classes, and static modifier is redundant.
    static class C { // violation
        public static boolean verifyState( A a ) {
            return true;
        }
    }

    public class E {} // violation

    // Enums are static implicit subclasses of Enum class.
    public enum Role1 { // violation
        ADMIN,
        EDITOR,
        VANILLA;
    }

    static enum Role2 { // violation
        ADMIN,
        EDITOR,
        VANILLA;
    }
}