title: How can interface achieve 100% abstraction in Java?
body: <p>I have this conceptual query.
  We say <strong>Interface</strong> is used to achieve 100% abstraction i.e. hide all the implementation.</p>
  
  <p>But in Interface, all the methods are declared abstract. 
  There is no implementation. </p>
  
  <p><strong><em>And when the other class implements the same interface then there is no more abstraction as the implementation is defined in the class which implements it.</em></strong></p>
  
  <p>Please throw some light on it.</p>