title: Add 30 days to Date in java
body: <p>why when i add 30 days to today's day i got today's day - 30, and when i add 20 it adds??</p>
  
  <p>here is a sample </p>
  
  <pre><code>import java.text.DateFormat;
  import java.util.Date;
  
  public class DatePlus
  {
  
      public static void main(String[] args)
      {
          Date now = new Date();
          Date now1 = new Date();
          Date now2 = new Date();
          DateFormat currentDate = DateFormat.getDateInstance();
  
          Date addedDate1 = addDays(now2, 20);
          Date addedDate2 = addDays(now1, 30);
          System.out.println(currentDate.format(now));
          System.out.println(currentDate.format(addedDate1));
          System.out.println(currentDate.format(addedDate2));
      }
  
      public static Date addDays(Date d, int days)
      {
          d.setTime(d.getTime() + days * 1000 * 60 * 60 * 24);
          return d;
      }
  }
  </code></pre>
  
  <p>"this is the console"</p>
  
  <pre><code>Jul 30, 2012
  Aug 19, 2012
  Jul 10, 2012
  </code></pre>