<div>
Agreed with CEHJ, it's an implementation.<br />
<br />
prsubject, <br />
please refer <b><a href="http://www.javaworld.com/javaworld/javaqa/2001-04/03-qa-0420-abstract.html?page=1" rel="ugc">http://www.javaworld.com/javaworld/javaqa/2001-04/03-qa-0420-abstract.html?page=1</a></b> for more understanding.
</div>


Agreed with CEHJ, it's an implementation.

prsubject,
please refer http://www.javaworld.com/javaworld/javaqa/2001-04/03-qa-0420-abstract.html?page=1 [http://www.javaworld.com/javaworld/javaqa/2001-04/03-qa-0420-abstract.html?page=1] for more understanding.

<div>
<div class="content wysiwyg-content">
Generally when anyone says when or why do we use Interface instead of extending from class, the answer immideately given is Java doesn't support multiple inheritence hence we use interface. Some people say that it is bookish and the more better answer is if we do not have a clear idea about the code that goes into that function we frame the interface if not we can go for abstract class. <br />
<br />
My question is if we do not have a clear idea about the functionality how come we could design the interface.
</div>
</div>


Generally when anyone says when or why do we use Interface instead of extending from class, the answer immideately given is Java doesn't support multiple inheritence hence we use interface. Some people say that it is bookish and the more better answer is if we do not have a clear idea about the code that goes into that function we frame the interface if not we can go for abstract class. 

My question is if we do not have a clear idea about the functionality how come we could design the interface.

Interface vs Abstract Class

Java is a platform-independent, object-oriented programming language and run-time environment, designed to have as few implementation dependencies as possible such that developers can write one set of code across all platforms using libraries. Most devices will not run Java natively, and require a run-time component to be installed in order to execute a Java program.

Java

Java Enterprise Edition (Java EE) is a specification defining a collection of Java-based server and client technologies and how they interoperate. Java EE specifies server and client architectures and uses profiles to define technology sets targeted at specific classes of applications. All Java EE profiles share a set of common features, such as naming and resource injection, packaging rules and security requirements.