Tomcat与Jetty JNDI Lookup

Question

I use Spring to configure my Java Web App and in my Spring configuration I obtain a datasource via JNDI for Jetty as follows:

<jee:jndi-lookup id="dataSource" jndi-name="jdbc/myDataSource" />

but this won't work with Tomcat. With Tomcat I have to do this:

<jee:jndi-lookup id="dataSource" jndi-name="java:comp/env/jdbc/myDataSource" />

Whats the best way to solve this? I am already using JNDI as a way to externalize configuration, so I can't externalize my externalized configuration! At the same time I absolutely loath the idea of having two separate Spring configuration files. HELP!!!

Answer 1

I found an answer here , but I thought it was a bit complicated, but it did give me the idea to use the very cool ServerDetector class that blogger had found.

Once I can dynamically figure what type of server I am running in, I was able to use the Spring expression language to do the rest of the work:

<jee:jndi-lookup id="myAppDataSource" 
    jndi-name="#{ (AppServerType == 'Jetty' ? 'jdbc/' : 'java:comp/env/jdbc/') + 
                  'myAppDataSource' }" />

Easy!

Answer 2

After some experimenting, I figured out I could just force Jetty to use the same JNDI path as Tomcat. The following snippet is from my jetty-env.xml file:

 <New id="myDataSource" class="org.mortbay.jetty.plus.naming.Resource">
  <!-- We MUST specify the entire JNDI path here to force compliance with the Tomcat/J2EE convention -->
  <Arg>java:comp/env/jdbc/myDataSource</Arg>
  <Arg>
   <New class="com.atomikos.jdbc.nonxa.AtomikosNonXADataSourceBean">
    <Set name="uniqueResourceName">sbeDatabase</Set>
                 ...............
   </New>
  </Arg>
 </New>

Not sure if this is ideal, but it works.

Update :

It works if you put your jetty-env.xml file inside the WAR...but for whatever reason, one you move this configuration outside the WAR and into a context fragment file in Jetty's "contexts" directory then it throws an exception:

Check it out: http://jira.codehaus.org/browse/JETTY-273

Answer 3

The cleanest way to do it is to configure your configuration. ;)

Use a Spring property place holder. See

http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/beans.html#beans-factory-placeholderconfigurer

The basic idea is that you just put a placeholder in your spring config with a property, and then it reads matching property from a properties file. You generate the properties file in your build process. Ive seen it done where the build tool (ant) reads an environment variable and then creates a properties file appropriate for the environment based of a skeleton file populated with tokens.