JDBC connection error on a share Tomcat host

[Chan Yan]

Hello everyone,
I use a Shared Tomcat Java hosting to host my site and have below error message:

org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'null'
org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:780)
org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:540)
com.swlAdminJ.bo.AdminLoginBO.findByName(AdminLoginBO.java:30)
com.swlAdminJ.action.login.LoginSubmitAction.execute(LoginSubmitAction.java:30)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
 

But I don't have any problem to run on my local computer (I use Tomcat 5.5.25), and my site runs well on the local computer.

When I read doc on 'http://tomcat.apache.org/tomcat-5.5-doc/jndi-resources-howto.html'. I found this paragraph in the page:

In addition, the names and values of all <env-entry> elements included in the web application deployment descriptor (/WEB-INF/web.xml) are configured into the initial context as well, overriding corresponding values from conf/server.xml only if allowed by the corresponding <Environment> element (by setting the override attribute to "true").


Does anyone know how to this 'override' attribute to "true"? where is it suppose to be? Is it the issue to cause the error?

Thanks in advance.

----------
Here is my context.xml (under '/public_html/META-INF/') and part of web.xml (under '/public_html/WEB-INF/'). I have a test.jsp to test the connection. I found the error occurs at this line in class DBTest.java

conn = ds.getConnection();
-----------------

<?xml version="1.0" encoding="UTF-8"?>
<Context >
  <Resource
    name="jdbc/myDataSource"
    auth="Container"
    description="DB Connection"
    type="javax.sql.DataSource"
    driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql://localhost/mydb?relaxAutoCommit=true"
    username="myusername"
    password="mypassword"   
    maxActive="20"
    maxIdle="2"
    maxWait="5000"
    validationQuery="select 1"
    />
  <WatchedResource>WEB-INF/web.xml</WatchedResource>
  <WatchedResource>META-INF/context.xml</WatchedResource>
</Context>
 
 
 
 
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
version="2.4" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee   
<a href="http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">" target="_blank" rel="nofollow">http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"></a>
<resource-ref>
<description>DB Connection</description>
<res-ref-name>jdbc/myDataSource</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref> 
......
</web-app>
 
 
package com.test;
 
import javax.naming.*;
import javax.sql.*;
import java.sql.*;
 
public class DBTest 
{
  String foo = "Not working";
  
    
  public void init() {
    try{
        Connection conn = null;
        Statement stmt = null;
        Context initContext = new InitialContext();
        foo = "after initContext";
        if(initContext == null ) 
        {
        foo = "after initContext == null";
        throw new Exception("Boom - No Context");
        }
        Context envCtx = (Context)initContext.lookup("java:comp/env");
        foo = "after env";
        DataSource ds = (DataSource) envCtx.lookup("jdbc/myDataSource");
        foo = "after ds";
       
        
      if (ds == null)
      foo = "ds == null";
      else
      {
    foo = "before conn";
        conn = ds.getConnection();
        foo = "after conn";      
        if(conn != null)  
        {
            foo = "Got Connection "+conn.toString();
            stmt = conn.createStatement();
            foo = "after stmt";
            ResultSet rst = stmt.executeQuery("select CATEGORY_NAME from link_category "+
            "where CATEGORY_ID =103");
            foo = "after rst";
            if(rst.next()) 
            {
               foo=rst.getString("CATEGORY_NAME");
            }
            conn.close();
        }
        else
        foo = "conn == null";
      }
            
    }catch(Exception e) 
    {
      e.printStackTrace();
      //foo = e.toString();
    }
 }
 
 public String getFoo() { return foo; }
 
}
 
<html>
  <head>
    <title>DB Test</title>
  </head>
  <body>
 
  <%
    com.test.DBTest tst = new com.test.DBTest();
    tst.init();
  %>
 
<h2>Results</h2>
    Foo <%= tst.getFoo() %><br/>
 
  </body>
</html>
 
<html>
  <head>
    <title>DB Test</title>
  </head>
  <body>
 
  <%
    com.test.DBTest tst = new com.test.DBTest();
    tst.init();
  %>
 
<h2>Results</h2>
    Foo <%= tst.getFoo() %><br/>
 
  </body>
</html>
 

[ October 15, 2007: Message edited by: Bear Bibeault ]

[Bear Bibeault]

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bear
JavaRanch Sheriff
[ October 15, 2007: Message edited by: Bear Bibeault ]