I'm using Java 1.6, tomcat 6.0.16/6.0.20 and axis2 1.4.1. I can't get my
servlets to talk to Oracle. All I get is "[ERROR] Cannot create JDBC driver of
class '' for connect URL 'null'"
I have tried to get answers on the tomcat users list and the Axis2 users list,
but after 2 weeks, I'm very little further forward and I think I'm going to
have to dig into the source code to find out where the problem lies. I would
appreciate some pointers to which bits of the source code are most relevant.
I have created a mimimal servlet purely to investigate this problem.
The code is
package com.example.dbservlet;
import java.lang.Exception;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.sql.DataSource;
public class DBServlet
{
private static final String DB_NAME = "jdbc/TestDatabase";
private static final String CONTEXT_NAME = "java:/comp/env";
public DBServlet()
{}
private Connection getConnection ()
throws Exception, SQLException
{
Context initContext = new InitialContext();
Context envContext = (Context) initContext.lookup(CONTEXT_NAME);
DataSource ds = (DataSource)envContext.lookup(DB_NAME);
return ds.getConnection();
}
public String getTime() throws Exception, SQLException
{
String time = "";
Connection conn = getConnection();
PreparedStatement stat = conn.prepareStatement(
"SELECT TO_CHAR( SYSDATE, 'YYYY-MM-DD HH24:MI FROM DUAL" );
ResultSet rSet = stat.executeQuery();
if( rSet.next() )
{
time = rSet.getString(1);
}
stat.close();
rSet.close();
return time;
}
}
In servlet-example/webapps/axis2/META-INF/context.xml I have
<Context>
<Resource name="jdbc/TestDatabase" auth="Container"
type="javax.sql.DataSource"
driverClassName="oracle.jdbc.OracleDriver"
url="jdbc:oracle:thin:@frogfoot:1521:w2"
username="********" password="********"
maxActive="20" maxIdle="10"
maxWait="-1"/>
</Context>
In servlet-example/webapps/axis2/WEB-INF/web.xml I have
...
<resource-ref>
<description>Oracle Test Datasource</description>
<res-ref-name>jdbc/TestDatabase</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
...
When I try to call getTime() the full traceback is
[ERROR] Cannot create JDBC driver of class '' for connect URL 'null'
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at
org.apache.axis2.rpc.receivers.RPCUtil.invokeServiceClass(RPCUtil.java:165)
at
org.apache.axis2.rpc.receivers.RPCMessageReceiver.invokeBusinessLogic(RPCMessageReceiver.java:102)
at
org.apache.axis2.receivers.AbstractInOutMessageReceiver.invokeBusinessLogic(AbstractInOutMessageReceiver.java:40)
at
org.apache.axis2.receivers.AbstractMessageReceiver.receive(AbstractMessageReceiver.java:100)
at org.apache.axis2.engine.AxisEngine.receive(AxisEngine.java:176)
at
org.apache.axis2.transport.http.HTTPTransportUtils.processHTTPPostRequest(HTTPTransportUtils.java:275)
at
org.apache.axis2.transport.http.AxisServlet.doPost(AxisServlet.java:133)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
at
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
at java.lang.Thread.run(Thread.java:619)
Caused by: org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create JDBC
driver of class '' for connect URL 'null'
at
org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1150)
at
org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:880)
at com.example.dbservlet.DBServlet.getConnection(DBServlet.java:44)
at com.example.dbservlet.DBServlet.getTime(DBServlet.java:51)
... 25 more
Caused by: java.lang.NullPointerException
at sun.jdbc.odbc.JdbcOdbcDriver.getProtocol(JdbcOdbcDriver.java:507)
at sun.jdbc.odbc.JdbcOdbcDriver.knownURL(JdbcOdbcDriver.java:476)
at sun.jdbc.odbc.JdbcOdbcDriver.acceptsURL(JdbcOdbcDriver.java:307)
at java.sql.DriverManager.getDriver(DriverManager.java:253)
at
org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1143)
... 28 more
[ERROR] Cannot create JDBC driver of class '' for connect URL 'null'
org.apache.axis2.AxisFault: Cannot create JDBC driver of class '' for connect
URL 'null'
at
org.apache.axis2.rpc.receivers.RPCMessageReceiver.invokeBusinessLogic(RPCMessageReceiver.java:158)
at
org.apache.axis2.receivers.AbstractInOutMessageReceiver.invokeBusinessLogic(AbstractInOutMessageReceiver.java:40)
at
org.apache.axis2.receivers.AbstractMessageReceiver.receive(AbstractMessageReceiver.java:100)
at org.apache.axis2.engine.AxisEngine.receive(AxisEngine.java:176)
at
org.apache.axis2.transport.http.HTTPTransportUtils.processHTTPPostRequest(HTTPTransportUtils.java:275)
at
org.apache.axis2.transport.http.AxisServlet.doPost(AxisServlet.java:133)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
at
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
I have used strace to see whether it is accessing the context.xml file and it
seems to be checking for it's existence, but not trying t open it, as I see a
stat() call, but no open()
/tmp/catalina.trace.3726:stat64("/home/neil/wirefast/dev/tomcat6/servlet-example/webapps/axis2/META-INF/context.xml",
{st_mode=S_IFREG|0644, st_size=343, ...}) = 0
Neil Youngman
