FULL PRODUCT VERSION :
java version "1.8.0_60"
Java(TM) SE Runtime Environment (build 1.8.0_60-b27)
Java HotSpot(TM) 64-Bit Server VM (build 25.60-b23, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
I want my Java program to add weeks in year to a given week, which is in "yyyyww" format.

For example I have "201701" which indicates 1st week of the year 2017. I want to add 2 weeks to this value. So I use "add" method of java.util.Calendar class (more details mentioned in source code). I get 201703. Perfect till now.

If I add 1 week to 201752 then I get 201801. Perfect.

But when I add 1 week to 201852 then I get 201801. Oops!


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
201901
ACTUAL -
201801

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
final String startWeek = "201852";

SimpleDateFormat sdf = sdf = new SimpleDateFormat("yyyyww");

Calendar calStart = Calendar.getInstance();

calStart.setTime(sdf.parse(startWeek));

calStart.add(Calendar.WEEK_OF_YEAR, 1);

System.out.println(sdf.format(calStart.getTime()));

---------- END SOURCE ----------