title: clone() not visible
body: <p>I have a class:</p>
  
  <pre><code>public class CounterBag&lt;T extends Additive&lt;T&gt; &amp; Cloneable &amp; Serializable&gt; {
      private T cntData;
  
      // c'tor, accessors equals and hashcode... 
      public T getCounterData() {
         return cntData;
      }
  }
  </code></pre>
  
  <p>other class <code>Service</code> has a member of type <code>Set&lt;CounterBag&gt;</code>.
  Now inside the <code>Service</code> I want to lookup for specific <code>CounterBag</code> and return a clone of its <code>cntData</code> member.</p>
  
  <p>When inside the lookup method of the <code>Service</code> class I detect the instance of the <code>CounterBag</code> in the set and try to the following:</p>
  
  <pre><code>return counterBag.getCounterData().clone();
  </code></pre>
  
  <p>the <code>clone()</code> seems not to be visible.</p>
  
  <p>I wonder what needs to be done to make the <code>clone()</code> visible? </p>