title: java calculate time between two timestamps
body: <p>I need to calculate the time passed between two dates.</p>
  
  <p>The catch here is that I need to show it as YouTube does with its video comments timestamps. That is, to show it by just the largest measure.</p>
  
  <p>For example,</p>
  
  <ul>
  <li>if the time is 50 seconds ago it should say 50 seconds ago.</li>
  <li>if the time is more than one minute it should say one minute ago/ten minutes ago etc..</li>
  <li>if the time difference is 1 hour 30 mins it should show: an hour ago.</li>
  <li>if the time is one and a half week than it should say one week ago. </li>
  <li>if the time is more than a month it should say one month ago/two months ago etc...</li>
  <li>and so on and so on..</li>
  </ul>
  
  <p>So what is the best way to handle this?
  Should I make a method with <code>case</code> or <code>if</code> statements that would return something like this? Or is there a better approach (maybe a library which already does something like it)?</p>