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On 17/04/2011 02:31, Esteban Aliverti wrote:
<blockquote
cite="mid:BANLkTin8d4D43TVmFYPe9AB9yf_AZ5kuJA@mail.gmail.com"
type="cite">
<p>Thanks pablo (aka baunax)!<br>
I agree that resource -> file: is not always possible. But
what about resource -> URL? After all, i'm converting
resources to URLs.</p>
</blockquote>
The URL will have a pointer to the file inside of the jar.<br>
<a class="moz-txt-link-freetext" href="http://www.exampledepot.com/egs/java.net/JarUrl.html">http://www.exampledepot.com/egs/java.net/JarUrl.html</a><br>
<br>
Mark<br>
<blockquote
cite="mid:BANLkTin8d4D43TVmFYPe9AB9yf_AZ5kuJA@mail.gmail.com"
type="cite">
<p>Best regards,<br>
</p>
<div class="gmail_quote">El abr 16, 2011 5:18 p.m., "Pablo
Nussembaum" <<a moz-do-not-send="true"
href="mailto:baunax@gmail.com">baunax@gmail.com</a>>
escribió:<br type="attribution">
> Sorry "IF I *wasn't* clear" :-P<br>
> <br>
> On 04/16/2011 05:11 PM, Pablo Nussembaum wrote:<br>
>> Sorry if I was clear. The problem when you do:
ClassLoader.getResource( "resource.path" ) is the the resource
can be inside a war the in WEB-INF/classes and the war could be
NOT exploded in<br>
>> container that's is deployed, so the translation to
something like <a class="moz-txt-link-freetext" href="file://">file://</a> is NOT reliable.<br>
>><br>
>> On 04/16/2011 05:05 PM, Mauricio Salatino wrote:<br>
>>> I'm still thinking about that mapping and those
assumptions<br>
>>><br>
>>> On Sat, Apr 16, 2011 at 5:05 PM, Mauricio Salatino
<<a moz-do-not-send="true" href="mailto:salaboy@gmail.com">salaboy@gmail.com</a>
<mailto:<a moz-do-not-send="true"
href="mailto:salaboy@gmail.com">salaboy@gmail.com</a>>>
wrote:<br>
>>><br>
>>> Can you? or Can't you?<br>
>>><br>
>>><br>
>>><br>
>>> On Sat, Apr 16, 2011 at 4:24 PM, Pablo Nussembaum
<<a moz-do-not-send="true" href="mailto:baunax@gmail.com">baunax@gmail.com</a>
<mailto:<a moz-do-not-send="true"
href="mailto:baunax@gmail.com">baunax@gmail.com</a>>>
wrote:<br>
>>><br>
>>> Esteban,<br>
>>> You can assume that a resource that was obtained
from the classpath exists in your filesystem, for instance it
can be a file inside a jar or war that are not exploded. In
other words you<br>
>>> can't always convert an URL to <a class="moz-txt-link-rfc2396E" href="file://">"file://"</a>.<br>
>>><br>
>>> -- <br>
>>> Bauna<br>
>>><br>
>>><br>
>>> On 04/15/2011 08:52 AM, Esteban Aliverti wrote:<br>
>>>> Hi Guys,<br>
>>>><br>
>>>> I want to discuss a problem I have found when
using the combination of knowledge agent + classpathResources.<br>
>>>> I will try to describe what am I doing first to
give you some context. <br>
>>>> I'm deploying drools-camel-server in a Tomcat 7
container. Inside the WEB-INF/classes directory I have some DRL
files that I want to use.<br>
>>>> My knowledge-services.xml file declares the
following kagent:<br>
>>>><br>
>>>> <drools:kagent id="kagent1" kbase="kbase1"
new-instance="false"><br>
>>>> <drools:resources> <br>
>>>> <drools:resource type="DRL"
source="*classpath*:simple.drl"/><br>
>>>> ... <br>
>>>> </drools:resources><br>
>>>> </drools:kagent><br>
>>>><br>
>>>> When spring parses this configuration file it
creates a KnowledgeAgent instance with a ChangeSet containing
all the listed resources.<br>
>>>> The next step is to start
ResourceChangeNotifierService and ResourceChangeScannerService.
<br>
>>>> So far so good.<br>
>>>><br>
>>>> The problem:<br>
>>>> The problem I'm having is not directly related
to drools, but I think it is quite easy to provide a solution
for the people that is in my same situation.<br>
>>>><br>
>>>> ClassPathResource is the class that represents
a resource defined as "*classpath:"*<br>
>>>><br>
>>>> This class has 2 important methods:<br>
>>>><br>
>>>> public long getLastModified(){<br>
>>>> return this.classLoader.getResource( this.path
).openConnection().getLastModified();<br>
>>>> }<br>
>>>><br>
>>>> public InputStream getInputStream(){<br>
>>>> return this.classLoader.getResourceAsStream(
this.path );<br>
>>>> }<br>
>>>><br>
>>>><br>
>>>> The first method is used by
ResourceChangeScannerService to check whether the resource has
changed or not. It works fine. When the resource in the
filesystem changes, the scanner detects<br>
>>>> the change without any problem.<br>
>>>> The scanner ends up notifying the kagent about
the change, and the kagent passes the Resource to an instance of
KnowledgeBuilder. <br>
>>>> An here is when things fail.<br>
>>>> The kbuilder uses the second method of
ClassPathResource (getInputStream()) to get the content of the
resource. In the case of Tomcat (and probably some other
environments), it seems that<br>
>>>> the classloader (Tomcat's classloader) is using
a cache. So the InputStream returned doesn't reflect the current
state of the resource.<br>
>>>> Long story short: the agent is notified about a
change in the resource, but the change is never applied to the
kbase because the kbuilder is unable to get it :P<br>
>>>><br>
>>>> Solutions:<br>
>>>> The first solution is not to use classpath
resources :). You can use just url resources like <a class="moz-txt-link-freetext" href="http://">http://</a> or
<a class="moz-txt-link-freetext" href="file:/">file:/</a>. But honestly, when you have your rules inside your
webapp, it is much<br>
>>>> more comfortable and even manageable to avoid
the use of real paths.<br>
>>>><br>
>>>> What I was thinking about (I already have a
working prototype) is to create a new Resource type for these
cases. This resource type will let you define your resources
present in your<br>
>>>> classpath as usually but it will translate them
to URL Resource internally.<br>
>>>> So, in the example above: <br>
>>>><br>
>>>> <drools:resource type="DRL"
source="*URLClasspath*:simple.drl"/><br>
>>>><br>
>>>> is going to be translated (internally and in a
transparent way) to something like:
<a class="moz-txt-link-freetext" href="file:/usr/local/apache-tomcat-7/webapps/MyWebapp/WEB-INF/simple.drl">file:/usr/local/apache-tomcat-7/webapps/MyWebapp/WEB-INF/simple.drl</a>.<br>
>>>><br>
>>>> Opinions? <br>
>>>><br>
>>>> XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX<br>
>>>><br>
>>>> Esteban Aliverti<br>
>>>> - Developer @ <a moz-do-not-send="true"
href="http://www.plugtree.com">http://www.plugtree.com</a>
<<a moz-do-not-send="true" href="http://www.plugtree.com">http://www.plugtree.com</a>><br>
>>>> - Blog @ <a moz-do-not-send="true"
href="http://ilesteban.wordpress.com">http://ilesteban.wordpress.com</a><br>
>>>><br>
>>>><br>
>>>> _______________________________________________<br>
>>>> rules-dev mailing list<br>
>>>> <a moz-do-not-send="true"
href="mailto:rules-dev@lists.jboss.org">rules-dev@lists.jboss.org</a>
<mailto:<a moz-do-not-send="true"
href="mailto:rules-dev@lists.jboss.org">rules-dev@lists.jboss.org</a>>
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href="https://lists.jboss.org/mailman/listinfo/rules-dev">https://lists.jboss.org/mailman/listinfo/rules-dev</a><br>
>>><br>
>>> _______________________________________________<br>
>>> rules-dev mailing list<br>
>>> <a moz-do-not-send="true"
href="mailto:rules-dev@lists.jboss.org">rules-dev@lists.jboss.org</a>
<mailto:<a moz-do-not-send="true"
href="mailto:rules-dev@lists.jboss.org">rules-dev@lists.jboss.org</a>><br>
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href="https://lists.jboss.org/mailman/listinfo/rules-dev">https://lists.jboss.org/mailman/listinfo/rules-dev</a><br>
>>><br>
>>><br>
>>><br>
>>><br>
>>> -- <br>
>>> - CTO @ <a moz-do-not-send="true"
href="http://www.plugtree.com">http://www.plugtree.com</a> <br>
>>> - MyJourney @ <a moz-do-not-send="true"
href="http://salaboy.wordpress.com">http://salaboy.wordpress.com</a><br>
>>> - Co-Founder @ <a moz-do-not-send="true"
href="http://www.jbug.com.ar">http://www.jbug.com.ar</a><br>
>>> <br>
>>> - Salatino "Salaboy" Mauricio -<br>
>>><br>
>>><br>
>>><br>
>>><br>
>>> -- <br>
>>> - CTO @ <a moz-do-not-send="true"
href="http://www.plugtree.com">http://www.plugtree.com</a> <br>
>>> - MyJourney @ <a moz-do-not-send="true"
href="http://salaboy.wordpress.com">http://salaboy.wordpress.com</a><br>
>>> - Co-Founder @ <a moz-do-not-send="true"
href="http://www.jbug.com.ar">http://www.jbug.com.ar</a><br>
>>> <br>
>>> - Salatino "Salaboy" Mauricio -<br>
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