Adding days to a date in Java
JavaDateJava Problem Overview
How do I add x days to a date in Java?
For example, my date is 01/01/2012, using dd/mm/yyyy as the format.
Adding 5 days, the output should be 06/01/2012.
Java Solutions
Solution 1 - Java
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
Calendar c = Calendar.getInstance();
c.setTime(new Date()); // Using today's date
c.add(Calendar.DATE, 5); // Adding 5 days
String output = sdf.format(c.getTime());
System.out.println(output);
Solution 2 - Java
java.time
With the Java 8 Date and Time API you can use the LocalDate class.
LocalDate.now().plusDays(nrOfDays)
See the Oracle Tutorial.
Solution 3 - Java
Calendar cal = Calendar.getInstance();
cal.set(Calendar.DAY_OF_MONTH, 1);
cal.set(Calendar.MONTH, 1);
cal.set(Calendar.YEAR, 2012);
cal.add(Calendar.DAY_OF_MONTH, 5);
You can also subtract days like this: Calendar.add(Calendar.DAY_OF_MONTH, -5);
Solution 4 - Java
Here is some simple code that prints the date five days from now:
DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
Calendar c = Calendar.getInstance();
c.add(Calendar.DATE, 5);
System.out.println(dateFormat.format(c.getTime()));
Example output:
16/12/2021
See also: Calendar#add
Solution 5 - Java
If you're using Joda-Time (and there are lots of good reasons to - a simple, intuitive API and thread safety) then you can do this trivially:
new LocalDate().plusDays(5);
to add 5 days to today's date, for example.
EDIT: My current advice would be to now use the Java 8 date/time API
Solution 6 - Java
Simple, without any other API:
To add 8 days to the current day:
Date today = new Date();
long ltime = today.getTime()+8*24*60*60*1000;
Date today8 = new Date(ltime);