Re: Tools/frameworks for Java multi-core programming?
Robert Klemme wrote:
anthonycwmak wrote:
I am trying to find tools/frameworks that help with writing Java
program that can utilize multi-core CPU. So far I only found
Java programs can "utilize" multi-core CPUs out of the box.
You need do nothing special.
jconcurr, JOMP, JAMP, Ateji, but they all either requires special
shell command to compile and run the programs, or, in Ateji's case
use a special file extension which is converted to java file. This
doesn't seem to be ideal if I require to build multi-core programs
that can be built on Maven or similar,
Why is that an issue? Typically you can include custom build procedures
in a build tool / framework.
and requires them to run on an
enterprise environment or application server.
If you are on an JEE application server that will usually take care of
the concurrency. You typically need to use those APIs the JEE spec or
AS at hand provides to not interfere with the framework in bad ways
(e.g. by breaking transactions). That does not seem like a bad option
although AS come with their own learning curve.
Besides writing concurrent programs, by using Java Concurrency API
directly, to utilize the multi-core, are there other easier/simpler
way to create Java enterprise applications that utlize multi-core
CPUs? Preferably, just annotate my POJOs to make them multi-core
capable?
"Making a POJO multi-core capable" is meaningless. Using concurrency is
more like an architectural property of your application (even though you
need to take care to use POJOs properly - but it's not enough to make
POJOs thread safe). At this point I am suspecting that someone told you
modern Java programs must use multiple cores and you want to get it done
easily. Unfortunately that won't work: you need to understand the
particular issues associated with concurrency to properly craft such
applications - even if you use a framework that takes away a large part
of the work from you.
As Robert said, if you're writing enterprise apps using Java EE, then the
threading is already done. You should pretty much never explicitly code
a Java EE component to spawn a thread.
Java SE is another matter. You do have to use thread calls to spawn threads.
Once you have at least two threads in a program (and all Java programs do),
then you are multi-core capable.
Java programs that use threads are already multi-core capable.
Boom, done.
What are you really after?
--
Lew