title: Should implementing methods have JavaDoc commentary if the interface they implement has JavaDoc commentary
body: <p>Assume I have an interface as follows.</p>
  
  <pre><code>public interface MyInterface{
  
   /**
   * This method prints hello
   */
    void sayHello();
  
    /**
    * This method prints goodbye
    */
    void sayGoodBye();
  }
  </code></pre>
  
  <p>A concrete class implements these methods. Now do the methods in the concrete class also needs to define the javadocs on top of its method definition? I see some people just copying the same javadoc definition to the concrete class's implemented methods. I don't see this as a good practice because if we are to change the doc definition we need to change it in multiple places. </p>
  
  <p>what is the standard practice for this?</p>