Error confguring multiple contexts/data sources in Tomcat 5

[Neelesh A Korade]

Hello

I am using Tomcat 5.5.27. I have two web applications- App1 and App2. Below are some details-

App1 Data Source JNDI name - jdbc/DW_Pool

App1 web context name - tdwebapps

App2 Data Source JNDI name - jdbc/SQLPool_DW

App2 web context name - tdreports

My context.xml and server.xml are given at the end of this post.

When I start Tomcat with these configurations and try to access my application, I see the following error in the log-

Aug 25, 2009 10:14:12 PM org.eclipse.birt.report.data.oda.jdbc.JndiDataSource getConnection
INFO: javax.naming.NameNotFoundException: Name jdbc is not bound in this Context
Aug 25, 2009 10:14:12 PM org.eclipse.birt.data.engine.odaconsumer.ConnectionManager openConnection
SEVERE: Cannot open connection.


My questions are-
1) Where am I going wrong? How to get rid of this exception?
2) I referred to the Tomcat config documentation given at- http://tomcat.apache.org/tomcat-5.5-doc/config/index.html
However, I have not been able to understand the significance of Context.xml file exactly. If we can configure contrexts, resources etc. in server.xml file, what purpose does the Context.xml file serve?

My Context.xml file-

<?xml version="1.0" encoding="UTF-8"?>
<Context path="/" reloadable="true" crossContext="true">
	<Resource 
		name="jdbc/DW_Pool" 
		auth="Container" 
		type="javax.sql.DataSource"
		factory="org.apache.tomcat.dbcp.dbcp.BasicDataSourceFactory"
		maxActive="10" 
		maxIdle="10" 
		maxWait="10000"
		username="tempuser" 
		password="welcome" 
		driverClassName="net.sourceforge.jtds.jdbc.Driver"
		url="jdbc:jtds:sqlserver://hostname:1433/Database1"
	/>
	<Resource 
		name="jdbc/SQLPool_DW" 
		auth="Container" 
		type="javax.sql.DataSource"
		factory="org.apache.tomcat.dbcp.dbcp.BasicDataSourceFactory"
		maxActive="10" 
		maxIdle="10" 
		maxWait="10000"
		username="tempuser" 
		password="welcome" 
		driverClassName="net.sourceforge.jtds.jdbc.Driver"
		url="jdbc:jtds:sqlserver://hostname:1433/Database2"
    	/>
   
</Context>
 

My server.xml file-

  
<?xml version="1.0" encoding="UTF-8"?>
<Server>
  <Listener className="org.apache.catalina.core.AprLifecycleListener"/>
  <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener"/>
  <Listener className="org.apache.catalina.storeconfig.StoreConfigLifecycleListener"/>
  <Listener className="org.apache.catalina.mbeans.ServerLifecycleListener"/>
  <GlobalNamingResources>
    <Environment
      name="simpleValue"
      type="java.lang.Integer"
      value="30"/>
    <Resource
      auth="Container"
      description="User database that can be updated and saved"
      name="UserDatabase"
      type="org.apache.catalina.UserDatabase"
      pathname="conf/tomcat-users.xml"
      factory="org.apache.catalina.users.MemoryUserDatabaseFactory"/>
  </GlobalNamingResources>
  <Service
      name="Catalina">
    <Connector
        port="8080"
        redirectPort="8443"
        minSpareThreads="25"
        connectionTimeout="20000"
        maxSpareThreads="75"
        maxThreads="150">
    </Connector>
    <Connector
        port="8009"
        redirectPort="8443"
        protocol="AJP/1.3">
    </Connector>
    <Engine
        defaultHost="localhost"
        name="Catalina">
      <Realm className="org.apache.catalina.realm.UserDatabaseRealm"/>
      <Host
          appBase="webapps"
          name="localhost">
        <Context
            crossContext="true"
            path="/tdreports"
            reloadable="true">
          <Resource
            name="jdbc/SQLPool_DW"
            type="javax.sql.DataSource"
            password="welcome"
            driverClassName="net.sourceforge.jtds.jdbc.Driver"
            maxIdle="5"
            maxWait="5000"
            username="tempuser"
            url="jdbc:jtds:sqlserver://hostname:1433/Database2"
            maxActive="100"/>
        </Context>
        <Context
            crossContext="true"
            path="/tdwebapps"
            reloadable="true">
          <Resource
            auth="Container"
            name="jdbc/DW_Pool"
            type="javax.sql.DataSource"
            driverClassName="net.sourceforge.jtds.jdbc.Driver"
            password="welcome"
            maxIdle="10"
            maxWait="10000"
            username="tempuser"
            url="jdbc:jtds:sqlserver://hostname:1433/Database1"
            maxActive="10"
            factory="org.apache.tomcat.dbcp.dbcp.BasicDataSourceFactory"/>
        </Context>
      </Host>
    </Engine>
  </Service>
</Server>

[Tim Holloway]

Context.xml allows you to define the context for a single webapp in a discrete file. Effectively, all the context files are merged into server.xml. But by physically separating them, you can redeploy a single webapp without changing server.xml itself, which would require restarting the entire server.

As a fat-fingered user type, there's another benefit. If you damage server.xml, the entire Tomcat server may become unusable. So by editing only a single context file, you only put that particular webapp at risk.

Use of a separate context file became the preferred way to define a webapp context starting in Tomcat 4 and continuing to the present day. You can also include a copy of the context as META-INF/context.xml (I may have that mis-capitalized) in your WAR, which allows you to make "drag and drop" WARs complete with JNDI and other container definitions that normally would be external to the war.

[Neelesh A Korade]

Thank you Tim. That was helpful.

Could someone help me out with the data source lookup exception I am seeing?

[Tim Holloway]

I didn't see anything obvious, although if you define it twice (once in context and once globally), that might cause problems.

The only other thing is that you also have to define the resource in web.xml, if I'm not mistaken:

    <resource-ref id="datasource">
        <description>DB Connection</description>
        <res-ref-name>jdbc/DW_Pool</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
    </resource-ref>