title: How to increment time by 1 hour
body: <p>I have two time values. one for the previous login time and one for the current login time. 
  I have to increase previous time login by one hour. I have used the date format hh:mm:ss.
  This is my code snippet. </p>
  
  <pre><code>Date previous_time, current_time;
  
    if(previous_time.before(current_time)){
    Log.i("Time Comparision"," true");
   }
  </code></pre>
  
  <p>so instead of the above mentioned if condition, I have to add one hour to the previous_time and do the if condition. How to achieve this?</p>