title: Adding seconds to a Date
body: <p>I need add a certain time in seconds to my Date. For this, I'm making it:</p>
  
  <pre><code>Date startTime = dayStart(dateSelected);    
  startTime.setSeconds(startTime.getSeconds()+30);
  </code></pre>
  
  <p>But, for this way I get this alerts:</p>
  
  <p>Multiple markers at this line <br/><br/>
  - The method setSeconds(int) from the type Date is deprecated<br/>
  - The method getSeconds() from the type Date is deprecated</p>
  
  <p>What's the better way to don't get these deprecated alerts?</p>