Share a connection pool across multiple jvms

hi every1,
we've got several (core)java modules, each running in its own JVM (somtimes even on seperate machines, though on the same LAN) & each module interacts with a DB. we could maintain a seperate connection pool for each module & utilize it to increase the throughput.
along with these core modules we also have Tomcat which hosts the webbased frontend to our app, ofcourse in which we have implemented a ConnectionPool & use it to access the DB. This GUI-app is also hosted on the same LAN as the core modules & so is the DB server (mysql).
the question is... is it possible that somehow the core modules could 'use' the connection pool in Tomcat?
thanks,
-ksm

well... its not about backwards or forwards here. in our app both the core & GUI work independently. the GUI is just for the data-load, config etc...
since we needed to implement a connection pool for our core modules, all i was wondering is that if it would be possible to utilize the already made pool, the on which we made in Tomcat?

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<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee"
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<resource-ref>
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$CATALINA_HOME/webapps/DBTest/META-INF/context.xmlSince I would eventually like to package each webapp in its own war file, I prefer the second option above. This will enable me to place the context.xml file within the .war file. Currently, however, I am not using .war files.
For the DBTest webapp I have the following <context> element in webapps/DBTest/META-INF/context.xml:
<context path="/DBTest" docBase="/DBTest" debug="1">
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javax.servlet.ServletException: Unable to get connection, DataSource invalid: "org.apache.commons.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'null', cause: No suitable driver"
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</html>Now I know that this is a very long and detailed question and that it is unlikely that anyone is even going to read down this far, let alone take the time to study all that XML, but if anyone is able to tell me why this setup does not allow global connection pooling, I will be pretty *@&$**% impressed. I only wish I had duke dollars to give.
Jon

Okay, I went back and double checked that I can get the DBTest example working. It is described here: http://jakarta.apache.org/tomcat/tomcat-5.0-doc/jndi-datasource-examples-howto.html
I was not able to get it working exactly according to the tutorial, though. I was required to put the <context> element not in the conf/server.xml but in conf/Catalina/localhost/DBTest.xml. Then, with the DBTest/WEB-INF/web.xml as above, I was able to get the DBTest example working. The output of test.jsp (described above also) is the following:
Results
Foo hello
Bar 12345I would like to be able to put the <context> element in webapps/DBTest/META-INF/context.xml (as I think should be allowed) because then I would be able to include it in a war file that encompassed the entire web application. If I am forced to put the <context> element in a subdirectory of the conf directory, then I cannot include it in a war file and I will be unable to just drop my war files in the webapps directory and go. Instead I will have to drop my war files in the webapps directory, then go and fiddle around with the xml files in conf/Catalina/localhost/
But if I move the <context> element into webapps/DBTest/META-INF/context.xml then the example stops working. When I put it back in conf/Catalina/localhost/DBTest.xml everything is fine again.
Ok, no big deal. I guess my war file deployment will just have to be a little more complicated.
But what if I want the resource to be global??? If I remove the <Resource> and <ResourceParams> elements from the webapp-specific <context> element and put them in the <GlobalNamingResource> element in the conf/server.xml file I should have a global resource, right? I did this, then added a resource link to the <context> element (see above), however, the example stops working. I have tried both with and without the <resource-ref> element in web.xml.
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868844 wrote:
how many types of connection pool? i heard about some connection pool like super user,mega user,general but am not aware of that if any one please explain it what is it?Comming back to your question regarding different type of users in the connection pool, I believe you are talking about the user of the database and his priviliges. You will need to use a database account with create priviliges, if you want to be able to create tables, write back etc in the database. If it is all about reading the data from the database then all you need a regular database account with read priviliges.
Hope your question is answered.
Please award points if helpful.
Thanks,
-Amith.

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Edited by: 817804 on 2010-12-2 下午11:33

hi guys,
Recently, I have a requirement that I need create a connection pool with oracle database, for the application, there are many database users, I want to make those users share a connection pool. But how could I do?
So I create some news database users and grant those users connection through a proxy user id, and define connection string in my program as below:
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As my assumption, the above two connection string should share a connection pool which was created by proxy user id and proxy password. But as a result, those connections returned different sessionid, it means that they did not share same connection pool(I use sys_context('userenv', 'sessionid') to trace and check whether they use a same connection pool).
Could anybody give me advice?
Note that database version is 9i.
Edited by: 817804 on 2010-12-2 下午11:33

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