Why interfaces in java
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/416331/java-interfaces">Java Interfaces?</a>  </p>
</blockquote>



<p>I am not the newest to java but there is one thing in it that I could not understand till date that what is exactly the purpose solved by an interface? I know that in order to attach the multiple inheritance with java it can be used but that should not be the soul reason. And most of the other goals of an interface can be served by the abstract class. Even the books do not give a sufficient answer. </p>
