FULL PRODUCT VERSION :
java version "1.6.0_10-beta"
Java(TM) SE Runtime Environment (build 1.6.0_10-beta-b25)
Java HotSpot(TM) Client VM (build 11.0-b12, mixed mode, sharing)


ADDITIONAL OS VERSION INFORMATION :
Linux riemann 2.6.18.8-0.1-default #1 SMP Fri Mar 2 13:51:59 UTC 2007 i686 athlon i386 GNU/Linux


A DESCRIPTION OF THE PROBLEM :
List<Integer> list = new ArrayList<Integer>();
list.add(0);
list.add(1);
list.add(2);
list.add(3);
List<Integer> subList = list.subList(0,2);
list.add(4);
System.out.println(": "+subList.size());

yields

Exception in thread "main" java.util.ConcurrentModificationException
at java.util.SubList.checkForComodification(AbstractList.java:752)
at java.util.SubList.size(AbstractList.java:625)
at eu.simuline.arithmetics.left2right.SumMultArgs1.main(SumMultArgs1.java

although i think it must not.
adding elements to the backed list does not modify the sublist
and in particular not its size.



STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
just hack in the code in the description.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
no exception
ACTUAL -
Exception in thread "main" java.util.ConcurrentModificationException
at java.util.SubList.checkForComodification(AbstractList.java:752)
at java.util.SubList.size(AbstractList.java:625)
at eu.simuline.arithmetics.left2right.SumMultArgs1.main(SumMultArgs1.java


ERROR MESSAGES/STACK TRACES THAT OCCUR :
see above

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
class Test {

    public static void main(String[] args) {
List<Integer> list = new ArrayList<Integer>();
list.add(0);
list.add(1);
list.add(2);
list.add(3);
List<Integer> subList = list.subList(0,2);
list.add(4);
System.out.println(": "+subList.size());

    }
}

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

CUSTOMER SUBMITTED WORKAROUND :

i did not find any workaround.