What connectionpool should be used?

FesterWim · **Posted:** Wed Jan 07, 2004 3:54 am

When running hibernate the output shows something like "using build-in connection pool (not recommended)". Do I need to implement this myself (never done that, so probably it would be worse then the build-in one) or are there any (open-source) alternatives?

regards,

Wim

emmanuel · **Posted:** Wed Jan 07, 2004 4:09 am

Your app server connection pooling mecanism (if available)
c3p0 http://sourceforge.net/projects/c3p0
apache dbcp http://jakarta.apache.org/commons/dbcp/

FesterWim · **Posted:** Wed Jan 07, 2004 4:15 am

I don't use an app server, so I'll try with the apache connectionpool. Thanks!

emmanuel · **Posted:** Wed Jan 07, 2004 5:42 am

FYI, people here usually recommend c3p0 (and it's now in LGPL). I don't have opinion, I use Weblogic connection pool.

drj · **Posted:** Wed Jan 07, 2004 6:24 am

Just to clear things up a little...

FesterWim wrote:

I don't use an app server, so I'll try with the apache connectionpool. Thanks!

You don't need to have a fully-fledged application server (as in JBoss, Websphere, Weblogic etc...) to take advantage of the connection pooling. Tomcat (I am using 4.1.29) is configurable to make use of connection pooling. An example context (using apache dbcp) is listed below:

Code:

<Context path="/myApp" 
       reloadable="true" 
       docBase="C:\dev\eclipse\workspace\myApp"
       workDir="C:\dev\eclipse\workspace\myApp\work"
       debug="5">        

   ....
   
  <Resource name="jdbc/DataSource" auth="Container" 
    type="javax.sql.DataSource"/>

  <ResourceParams name="jdbc/DataSource">
    <parameter>
      <name>factory</name>
      <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
    </parameter>


    <!-- Maximum number of dB connections in pool. Make sure you
         configure your mysqld max_connections large enough to handle
         all of your db connections. Set to 0 for no limit.
         -->
    <parameter>
      <name>maxActive</name>
      <value>100</value>
    </parameter>

    <!-- Maximum number of idle dB connections to retain in pool.
         Set to 0 for no limit.
         -->
    <parameter>
      <name>maxIdle</name>
      <value>30</value>
    </parameter>

    <!-- Maximum time to wait for a dB connection to become available
         in ms, in this example 10 seconds. An Exception is thrown if
         this timeout is exceeded.  Set to -1 to wait indefinitely.
         -->
    <parameter>
      <name>maxWait</name>
      <value>10000</value>
    </parameter>

    <!-- MySQL dB username and password for dB connections  -->
    <parameter>
     <name>username</name>
     <value>user-xxxx</value>
    </parameter>
    <parameter>
     <name>password</name>
     <value>password-xxxx</value>
    </parameter>

    <!-- Class name for MyQSL JDBC driver -->
    <parameter>
       <name>driverClassName</name>
       <value>com.mysql.jdbc.Driver</value>
    </parameter>

    <!-- The JDBC connection url for connecting to your MySQL dB.
         The autoReconnect=true argument to the url makes sure that the
         mm.mysql JDBC Driver will automatically reconnect if mysqld closed the
         connection.  mysqld by default closes idle connections after 8 hours.
         -->
    <parameter>
      <name>url</name>
      <value>jdbc:mysql://localhost/myappDB?autoReconnect=true</value>
    </parameter>
  </ResourceParams>
    
  .... 

  </ResourceParams>

   
</Context>

Regards
Justin

paulwrussell · **Joined:** Mon May 23, 2005 4:32 am **Posts:** 4

Sorry, I am new to j2ee.

where should that file be placed? And what should it be named?

mox601 · **Posted:** Thu May 26, 2005 6:42 am

if you have configured the connection pooling with tomcat, could you post it here with some basic istructions? thanx