Round 2 feedback

Michael Nascimento misterm at
Wed Feb 13 06:29:10 PST 2013

On Sun, Feb 10, 2013 at 10:42 AM, Patrick Wright <pdoubleya at> wrote:
>> - Here is my greatest concern so far: parallel streams in their current
>> form will cause Java EE applications to fail miserably. In such
>> environments, threads cannot be freely created and all types of leaks and
>> exceptions can happen if one calls a method in a non-container managed
>> thread. Since calling parallelStream is cheap, I guess people will do it
>> often and it will be hard for Java EE developers to find out if any
>> third-party Java SE 8 code is safe to call or not - and enterprise
>> developers unaware of such restrictions, which are unfortunately the
>> majority, will be puzzled by never seen exceptions or erratic behaviour in
>> production. My suggestion would be to add a parameter to parallelStream
>> and
>> parallel which is an abstraction to thread management,  forcing people to
>> think about it. Then one can construct a wrapper over the
>> container-specific API for now and Java EE 8 can provide the standardized
>> one;
> It seems this is rather an ideal use for a Checkstyle rule or similar
> style-enforcer, e.g. to find calls to .parallelXXX and forbid them?

Well, not really since it can be in an "innocent" library somewhere or
in the future even inside the VM library code itself.


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