why we need interface instead of class and what we are achieving from interface
<p>As we know that we can declare only the method signature and also can not create the instance of a Interface. then why we need interface. Unnecessary its loading into JVM. This is also one performance degradation. We are creating the interface and several classes implementing that interface and defining all the methods of the interface. Actually what we achieved from this interface. Could you please give me some example.</p>
