title: java SimpleDateFormat.parse a UTC time to Asia/Hong_Kong Time
body: <p>from web, the date is in Asia/Hong_Kong format (UTC+8), but when pass to WildFly server using JSON format, in server debug mode, the date string become UTC format.
  e.g.</p>
  
  <p>web:Mon Oct 12 2015 00:00:00 GMT+0800 (Hong Kong Standard Time)<br>
  WildFly server:2015-10-11T16:00:00.000Z</p>
  
  <p>I want to use java SimpleDateFormat to parse it back to Asia/Hong_Kong format, I try</p>
  
  <pre><code>    String dateUTC="2015-10-11T16:00:00.000Z";
  
      SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy-MM-dd");
      System.out.println("sdf1.parse(dateUTC)="+sdf1.parse(dateUTC));
  
      SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy-MM-dd");
      sdf2.setTimeZone(TimeZone.getTimeZone("UTC"));
      System.out.println("sdf2.parse(dateUTC)="+sdf2.parse(dateUTC));
      SimpleDateFormat sdf3 = new SimpleDateFormat("yyyy-MM-dd");
      sdf3.setTimeZone(TimeZone.getTimeZone("Asia/Hong_Kong"));
      System.out.println("sdf3.parse(dateUTC)="+sdf3.parse(dateUTC));
  </code></pre>
  
  <p>I want the output to be "2015-10-12" but fail, the output is </p>
  
  <blockquote>
    <p>sdf1.parse(dateUTC)=Sun Oct 11 00:00:00 HKT 2015<br>
    sdf2.parse(dateUTC)=Sun Oct 11 08:00:00 HKT 2015<br>
    sdf3.parse(dateUTC)=Sun Oct 11 00:00:00 HKT 2015    </p>
  </blockquote>
  
  <p>1) So how to make the output to be "2015-10-12"? (As Hong Kong is UTC+8)?</p>
  
  <p>2) any method to make the server can receive the web datetime in Asia/Hong_Kong format, but not in UTC datetime format? I try to set WildFly java_opts by setting VM arguments</p>
  
  <pre><code>-Duser.timezone=Asia/Hong_Kong
  </code></pre>
  
  <p>but no use, the server still receive the datetime as UTC format.</p>