Re: Create new thread from Web Service

From:

=?ISO-8859-1?Q?Arne_Vajh=F8j?= <arne@vajhoej.dk>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 14 Jan 2009 18:53:59 -0500

Message-ID:

<496e7b0e$0$90262$14726298@news.sunsite.dk>

ShaneLM wrote:

Hi, I'm new to java web services and am trying to understand the
context in which they are run. Any pointers to the web service
lifecycle (specifically through Axis2) would be awesome.

My specific problem is that I'm trying to create a web service that
spawns a background process that will keep running after the web
service call completes. So far my research has given 2 possible
methods.

1) Create a new thread during the service call. My worries are that
this will get killed as soon as the web service returns, or that I
won't be able to maintain a handle on it when I want to kill the
thread later.

2) Use the Axis2 framework to develop an asynchronous service, as
described here http://www.ibm.com/developerworks/webservices/library/ws-axis2/

Would these methods work? Which would you recommend?

In either method, what's the best way to exchange data between this
background process and any future web service calls?

I don't know those features of Axis2. The first two are client side
and not relevant for your question. The third could be a solution
for you.

If you start a thread, then the thread will not be stopped when
the call returns and you will be able to get the data via some
global data structure - like a singleton.

But in general it is bad practice to start threads inside the
web container. The may sys admin have spend time tuning the
number of threads in the container.

The true Java EE way is to have the call put the job in a message
queue and have a MDB do the processing.

Arne