Help With Connection Pool

[Luke Shannon]

Hello;

I am trying to get a connection pool running in my application. I get the error:

javax.naming.NameNotFoundException: Name jdbc is not bound in this Context

Not sure what is going on here. Am I not getting a reference to the datasource in the correct way? Have I configured one of the files wrong? Any tips would be awesome.

Here is all my code.

server.xml (this context appears in the host tag)

<Context path="/PlayGround" docBase="E:\applications\eclipse\eclipse\workspace\PlayGround" reloadable="true">
 
  <Logger className="org.apache.catalina.logger.FileLogger"
      prefix="localhost_MyWebApp." suffix=".txt" timestamp="true"/>
 
  <Resource name="jdbc/PlayGround" auth="Container"
      type="javax.sql.DataSource"/>
 
  <ResourceParams name="jdbc/PlayGround">
    <parameter>
      <name>factory</name>
      <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
    </parameter>
 
    <!--
      | The JDBC connection URL for connecting to your MySQL DB.
      | The autoReconnect=true argument to the URL makes sure that the
      | 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>jjdbc:mysql://127.0.0.1/findworkstesting?autoReconnect=true</value>
    </parameter>
 
    <!--
      | MySQL username and password for DB connections.
      +-->
    <parameter>
      <name>username</name>
      <value>tester</value>
    </parameter>
    <parameter>
      <name>password</name>
      <value>t3st1ng</value>
    </parameter>
 
    <!--
      | Class name for MySQL JDBC driver.
      +-->
    <parameter>
      <name>driverClassName</name>
      <value>com.mysql.jdbc.Driver</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>50</value>
    </parameter>
 
    <!--
      | Maximum number of idle DB connections to retain in pool.
      | Set to 0 for no limit.
      +-->
    <parameter>
      <name>maxIdle</name>
      <value>10</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>
  </ResourceParams>
</Context>

Web.xml

<web-app xmlns="http://www.w3.org/2001/xml.xsd" version="2.4">
<!-- TESTING SERVLETS -->
<servlet>
<servlet-name>ConnectionTest</servlet-name>
<servlet-class>DB.ConnectionTest</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>ConnectionTest</servlet-name>
<url-pattern>/code/ConnectionTest.do</url-pattern>
</servlet-mapping>
<resource-ref>
<description>Playground Datasource.</description>
<res-ref-name>jdbc/PlayGround</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
</web-app>

Servlet Code:

protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
StringBuffer results = new StringBuffer();
try {
Context ctx = new InitialContext();
DataSource ds = (DataSource)ctx.lookup("jdbc/PlayGround");
Connection con = ds.getConnection();
PreparedStatement auctions = con.prepareCall("SELECT * FROM auction");
ResultSet rs = auctions.executeQuery();
while (rs.next()) {
results.append(rs.getString("8words"));
}
} catch (NamingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
PrintWriter out = response.getWriter();
out.print("The Result Of The Test Call Is:");
out.print(results.toString());
}

[ August 24, 2005: Message edited by: Luke Shannon ]

[Tom Blough]

I don't know if it is just a typo, but you have an extra "j" in the URL:

<parameter>
   <name>url</name>
      <value>jjdbc:mysql://127.0.0.1/findworkstesting?autooReconnect=true</value>
</parameter>

What server (Tomcat?) and version are you running under?

Cheers,
[ August 24, 2005: Message edited by: Tom Blough ]

[Luke Shannon]

Hi Tom;

Testing this under Tomcat 5, but it might have to run in Tomcat 4 (not sure how hard it will be to upgrade the server yet).

I found this tutorial:

http://jakarta.apache.org/tomcat/tomcat-4.1-doc/jndi-datasource-examples-howto.html

Based on that I made the following changes to my servlet method:

protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
StringBuffer results = new StringBuffer();
try {
Context ctx = new InitialContext();
DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/ConPool");
Connection con = ds.getConnection();
PreparedStatement auctions = con.prepareStatement("SELECT * FROM auction");
ResultSet rs = auctions.executeQuery();
while (rs.next()) {
results.append(rs.getString("eightWords"));
}
} catch (NamingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
PrintWriter out = response.getWriter();
out.print("The Result Of The Test Call Is:");
out.print(results.toString());
}

Everything work fine now :-)

Thanks,

Luke