title: Best way to store date and time in Sqlite database in Android to perform date operations easily
body: <p>I want to store date and time that user picks through date picker and time picker on Android. By reading various thread I came to conclusion to store date and time in INTEGER format. So I'm converting them to long values using following function but when I'm converting them back to Date it is giving me wrong Date.</p>
  
  <pre><code>private DatePickerDialog.OnDateSetListener startDatePickerListener = new DatePickerDialog.OnDateSetListener(){
  
      @Override
      public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
          String dateText = getTimeString(year,monthOfYear,dayOfMonth);
          //Converting Date to long so that can be stored in DB
          long date = Utility.getDateLong(year,monthOfYear,dayOfMonth);
          taskModel.setStartDate(date);
          startDateView.setText(dateText);
      }
  };
  
   public static long getDateLong(int year, int month, int day){
      Calendar cal = new GregorianCalendar(year, month, day);
      long timeStamp = (cal.getTimeInMillis()+cal.getTimeZone().getOffset(cal.getTimeInMillis()))/1000;
      return timeStamp;
  }
  </code></pre>
  
  <p>To convert long value back to Date I'm using the below function :</p>
  
  <pre><code>public static String getDateFromLongValue(long d){
      Date date = new Date(d);
      DateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy");
      String formattedDate = dateFormat.format(date);
      return formattedDate;
  }
  </code></pre>
  
  <p>But this is giving me the different date then the entered value. Is there any other way to do this. I basically need to compare dates and to find the time elapsed between two dates?</p>