Java - Creating a list of dates

Question

I am having trouble figuring a problem i have. I have to create a banking system which stores data of incoming and out going expenses, so far i have created an Array of objects each of which saves the Name, amount, and a number of weeks, eg 4. If i know that this expense happens every 4 weeks how can i auto generate dates starting from the 1st of this year to the end, for example, wage +4000, 1/1/12, wage +4000, 29/1/12 and so on?

How do i auto generate a list of dates if i know it should happen every X amount of weeks?

Answer 1

Here is an improvement on @Héctor van den Boorn answer.

Calendar date= Calendar.getInstance();
ArrayList<Calendar> dates = new ArrayList<>();

for (int i=0; i<10; i++)
{
  date.add(Calendar.WEEK_OF_YEAR, 4);
  // Create new instance of cal
  Calendar tmp= Calendar.getInstance();
  //Makes its inner values the same
  tmp.setTime(date.getTime());
  // Add unique instance to list
  dates.add(tmp);
}

Answer 2

You can use the Java Calendar class.

Calendar date= Calendar.getInstance();
ArrayList<Calendar> dates = new ArrayList<>();

for (int i=0; i<10; i++)
{
  date.add(Calendar.WEEK_OF_YEAR, 4);
  dates.add(date);
}