Interface

 Interface - lerde body-siz metodlar by default public abstract olur.

package main.example9;

public interface Worker {

    public abstract void work();
}

Interface - lerde variable-lar public static final olur. 

public static final String name = "Parvin";

Interface - lerde body-li metodlar yazmaq mumkundur. By default public olurlar.
package main;

public interface Runnable {
    public static final String name = "Parvin";

    public abstract void foo();

    public default void foo2() {
        System.out.println("foo2 in Runnable");
    }
}