title: "%02d" in android application code
body: <p>Application code is</p>
  
  <pre><code>DateTime startDate8 = DateTime.now(); 
  DateTime endDate8 = new DateTime(2014, 11, 5, 15, 0);
  
  Period period8 = new Period(startDate8, endDate8, PeriodType.dayTime());
  
  PeriodFormatter formatter8 = new PeriodFormatterBuilder()
      .appendMinutes()
      .toFormatter(); 
  
  tw.setText(String.format("%02d",formatter8.print(period8))); 
  </code></pre>
  
  <p>Application dont work.
  App has stopped unfortunately. What is problem in my code?</p>