title: Convert date to different timezone
body: <p>I am trying to obtain a simple conversion from one time zone into another using Java Date and Calendar. I am trying to run the following code</p>
  
  <pre><code>    Calendar instance = Calendar.getInstance(TimeZone.getTimeZone("Europe/London"));
      Date date = instance.getTime();
      System.out.println(date);
  
      GregorianCalendar instance2 = new GregorianCalendar(TimeZone.getTimeZone("Europe/Athens"));
      instance2.setTime(instance.getTime());
      System.out.println(instance2.getTime());
  </code></pre>
  
  <p>but that still returns the same date, rather than +1 hour... The whole problem seems trivial but i cannot find any simple answer to this. Thanks in advance for your help.</p>