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How to setup connection pool with GWT / Jetty in eclipse?

Sorry if this question seems repetitive, but I was unable to clarify a workable solution from the search results for existing posts.

I have a web application that uses a JDBC connection pool. The connection pool resource is defined in the war file of the meta-inf / context.xml file. When I deploy the war file to tomcat, this file is copied (and renamed to match the name of my war file) to the tomcat conf / catalina / localhost folder. My code gets the connection datasource object like this:

Context envCtx = (Context) new InitialContext().lookup("java:comp/env");
datasource = (DataSource) envCtx.lookup("jdbc/MYDB");

and my context.xml has the following resource:

<Resource name="jdbc/MYDB" 
      auth="Container" 
      type="javax.sql.DataSource"
      driverClassName="com.microsoft.sqlserver.jdbc.SQLServerDriver"
      username="username" 
      password="password" 
      url="jdbc:sqlserver://myremote.database.server:1433;databaseName=testdb"
      />

This all works well when the war file is deployed to tomcat.

However, during development in eclipse and due to GWT dependencies, I often have to debug using the GWT embedded in the jetty container.

When I do this, the InitialContext () call ends with the message:

javax.naming.NoInitialContextException: Need to specify class name in environment or system property, or as an applet parameter, or in an application resource file:  java.naming.factory.initial

I tried using jetty-env.xml in war web-inf but that didn't work either (same error), maybe syntax error in jetty-env.xml file or something.

Here is my pier:

<?xml version="1.0"?>
<!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "http://www.eclipse.org/jetty/configure.dtd">
<Configure id="Server" class="org.eclipse.jetty.server.Server">
<New id="OTMFTDB" class="org.eclipse.jetty.plus.jndi.Resource">
    <Arg></Arg>
    <Arg>jdbc/MYDB</Arg>
    <Arg>
        <New class="net.sourceforge.jtds.jdbcx.JtdsDataSource">
            <Set name="User">username</Set>
            <Set name="Password">password</Set>
            <Set name="DatabaseName">testdb</Set>
            <Set name="ServerName">myremote.database.server</Set>
            <Set name="PortNumber">1433</Set>
        </New>
    </Arg>
</New>
</Configure>

Lastly, if I change the name of jetty-env.xml to jetty-web.xml, then I get a 503 HTML error when I try to connect the browser. (eclipse shows the following error: [WARN] Failed to start context com.g oogle.gwt.dev.shell.jetty.JettyLauncher $ WebAppContextWithReload @ 111a20c {/, E: \ dev \ src \ servers \ webservice \ war} java.lang .ClassNotFoundException: org.eclipse.jetty.server.Server)

So, I believe jetty-env was not loaded but jetty-net, but my jetty is clearly interfering with the jetty-env settings for jetty.

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You are missing org.eclipse.jetty.server.Server, but I think it is not the correct class. GWT 2.5.1 uses jetty 6.1.11 and according to that is the org.eclipse.jetty package from Jetty 7, not 6!

I had a similar problem and solved it by adding the jetty-naming and jetty-plus libraries project to the project. This is a maven project, so I added it to the pom.xml:

<dependency>
    <groupId>org.mortbay.jetty</groupId>
    <artifactId>jetty-naming</artifactId>
    <version>6.1.11</version>
</dependency>
<dependency>
    <groupId>org.mortbay.jetty</groupId>
    <artifactId>jetty-plus</artifactId>
    <version>6.1.11</version>
</dependency>

Without maven, you can download jetty-naming and jetty-plus banks from the internet.

My resource is PostgreSQL JDBC driver. Everything now works - in host mode - the resource config loaded from jetty-web.xml. And when I create a war and deploy to Tomcat, the resource is obtained from context.xml.

context.xml:

<?xml version="1.0" encoding="UTF-8"?>
<Context antiJARLocking="true" path="/web">
    <Resource auth="Container" driverClassName="org.postgresql.Driver"
        maxActive="100" maxIdle="30" maxWait="200" name="jdbc/postgres"
        username="testuser" password="testpass" type="javax.sql.DataSource"
        url="jdbc:postgresql://localhost:5433/resolver" />
</Context>


Jetty-web.xml:

<?xml version="1.0"  encoding="ISO-8859-1"?>
<!DOCTYPE Configure PUBLIC "-//Mort Bay Consulting//DTD Configure//EN" "http://jetty.mortbay.org/configure.dtd">
<Configure class="org.mortbay.jetty.webapp.WebAppContext">
    <New id="GWT_HOSTED_MODE_DB" class="org.mortbay.jetty.plus.naming.Resource">
        <Arg>java:/comp/env/jdbc/postgres</Arg>
        <Arg>
            <New class="org.apache.commons.dbcp.BasicDataSource">
                <Set name="driverClassName">org.postgresql.Driver</Set>
                <Set name="url">jdbc:postgresql://localhost:5433/resolver</Set>
                <Set name="username">testuser</Set>
                <Set name="password">testpass</Set>
            </New>
        </Arg>
    </New>
</Configure>

Also my web.xml contains this link:

<resource-ref>
    <description>Postgres Connection pool datasource</description>
    <res-ref-name>jdbc/postgres</res-ref-name>
    <res-type>javax.sql.DataSource</res-type>
    <res-auth>Container</res-auth>
</resource-ref>

The data source is loaded like this (simplified):

DataSource dataSource = (DataSource) new InitialContext().lookup("java:/comp/env/jdbc/postgres");
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While I'm not familiar with your pier problem, I know that you can use your own servlet container instead of the GWT servlet container using the -noserver flag. It works great and allows me to use any other server in hosted mode.



http://code.google.com/webtoolkit/doc/latest/DevGuideCompilingAndDebugging.html#How_do_I_use_my_own_server_in_development_mode_instead_of_GWT

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