Is this javax.naming.NamingException related to error generated by Tomcat 7.0?

[Mark Curlette]

Hello,

I am new to Tomcat , and I tried to create a school project using eclipse and Tomcat 7.0.

I received a javax.naming.NamingException: Cannot create resource instance with root cause which I think it may relate to the Tomcat server. I tried to solve it but with my limited understanding of the Tomcat server, i was not able to find a good explanation for the problem.

So i hope if you could guide me to why did i have this kind of error and how to resolve it.

My simple jsp is calling a resource reference which i declared in the web.xml file

<%@ page import="javax.naming.InitialContext,commonj.timers.TimerManager" %>  
 <%  

System.out.println("\n\n\t ---------------1-------------");  

TimerManager timerManager = null;  

 try {  

InitialContext initContext = new InitialContext();  

timerManager = (TimerManager) initContext.lookup("java:comp/env/timer/TestTimer");  

System.out.println("\n\n\t I am able to Lookup: "+timerManager);  

 out.println("<b><font color=GREEN>\"timer/TestTimer\" Created Using DD</font> I am able to Lookup:</b>"+timerManager);  

}  

catch (Throwable anException)  

{  

throw new RuntimeException(anException);  

}  

 %> 

My web.xml file which contains the above resource reference as following

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>Listenering</display-name>
  
 

<resource-ref>  

        <res-ref-name>timer/TestTimer</res-ref-name>  

         <res-type>commonj.timers.TimerManager</res-type>  

         <res-auth>Container</res-auth>  

         <res-sharing-scope>non-shareable</res-sharing-scope>  

   </resource-ref>  
  
  
  
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
</web-app>

I don't know why it gave the error since the jsp is calling a resource reference, and the resource reference is defined in the web.xml. The error is as followed:

Jul 24, 2013 2:25:35 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [jsp] in context with path [/Listenering] threw exception [java.lang.RuntimeException: javax.naming.NamingException: Cannot create resource instance] with root cause
javax.naming.NamingException: Cannot create resource instance
	at org.apache.naming.factory.ResourceFactory.getObjectInstance(ResourceFactory.java:146)
	at javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:321)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:826)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:145)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:814)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:145)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:814)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:145)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:814)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:159)
	at org.apache.naming.SelectorContext.lookup(SelectorContext.java:158)
	at javax.naming.InitialContext.lookup(InitialContext.java:411)
	at org.apache.jsp.NewFile_jsp._jspService(NewFile_jsp.java:68)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:419)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:391)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:562)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:395)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:250)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:166)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
	at java.lang.Thread.run(Thread.java:722)

I read some related article and it suggested that I need to declare the resource ref in context.xml. I don't why since I already declared it in web.xml. Is is not enough for Tomcat 7 to recognize?

If i declare it again in context.xml, then should it be exacly the same as I declared it in web.xml ?? such as the following :

<resource-ref>  

        <res-ref-name>timer/TestTimer</res-ref-name>  

         <res-type>commonj.timers.TimerManager</res-type>  

         <res-auth>Container</res-auth>  

         <res-sharing-scope>non-shareable</res-sharing-scope>  

   </resource-ref>  

Thanks so much in advance for your consideration.

Tom

[Tim Holloway]

I'm going to let Bear growl at you for using scriptlets in the first place. Here's some info on JNDI and Tomcat.

You define a JNDI resource in web.xml, that is true. Here's one of mine:

    <env-entry>
        <description>ETS Polling Interval, in milliseconds.</description>
        <env-entry-name>ets/pollInterval</env-entry-name>
        <env-entry-type>java.lang.String</env-entry-type>
        <env-entry-value>600000</env-entry-value>
    </env-entry>

You can optionally set an override in the Tomcat Context definition, but the syntax is different:

    <Environment name="ets/pollInterval" value="4000000"
         type="java.lang.String" override="false"/>

Note that the "override" attribute in Context indicates when web.xml overrides the Context, so it's the reverse of what you might think.

[Mark Curlette]

Hello Tim,

Thanks for the pointer, I add the resource name reference to my context.xml but somehow Tomcat still gave me the error message saying that " javax.naming.NamingException: Cannot create resource instance with root cause".

I did not know why it did not work as it should. Please take a look to see if you could find anything unusual.

Thanks so much in advance for all of your help!!

Tom

my web.xml again is as following :

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>Listenering</display-name>
  
 

<resource-ref>  

        <res-ref-name>timer/TestTimer</res-ref-name>  

         <res-type>commonj.timers.TimerManager</res-type>  

         <res-auth>Container</res-auth>  

         <res-sharing-scope>Shareable</res-sharing-scope>  

   </resource-ref>  
  
  
  
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
</web-app>

My context.xml is as the following:

<?xml version="1.0" encoding="UTF-8"?>
<Context>

    <!-- Default set of monitored resources -->
    <WatchedResource>WEB-INF/web.xml</WatchedResource>

    <!-- Uncomment this to disable session persistence across Tomcat restarts -->
    <!--
    <Manager pathname="" />
    -->

    <!-- Uncomment this to enable Comet connection tacking (provides events
         on session expiration as well as webapp lifecycle) -->
    <!--
    <Valve className="org.apache.catalina.valves.CometConnectionManagerValve" />
    -->

<Resource name="timer/TestTimer" auth="Container"
            type="commonj.timers.TimerManager"/>
</Context>

and finally the following run time exception error saying it can not create the resource reference

SEVERE: Servlet.service() for servlet [jsp] in context with path [/Listenering] threw exception [java.lang.RuntimeException: javax.naming.NamingException: Cannot create resource instance] with root cause
javax.naming.NamingException: Cannot create resource instance
	at org.apache.naming.factory.ResourceFactory.getObjectInstance(ResourceFactory.java:146)
	at javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:321)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:826)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:145)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:814)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:145)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:814)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:145)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:814)
	at org.apache.naming.NamingContext.lookup(NamingContext.java:159)
	at org.apache.naming.SelectorContext.lookup(SelectorContext.java:158)
	at javax.naming.InitialContext.lookup(InitialContext.java:411)
	at org.apache.jsp.NewFile_jsp._jspService(NewFile_jsp.java:68)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:419)
	at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:391)
	at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:562)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:395)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:250)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:166)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
	at java.lang.Thread.run(Thread.java:722)

[Tim Holloway]

Why are you using resource-ref? That's commonly used to reference factory objects.

[Mark Curlette]

Thank you very much Tim. You are absolutely right. I got rid of resource reference and replace it with your env-entry and it worked well.
I was able to Lookup: 4000000 from both of my jsp and eclipse console.

I would like to ask you an additional question if you don't mind relating to a class project which simply print out a stock quote and email in every ten minutes. It requires using the servlet context listener.

I would like to ask you please check my logic and please correct me if you spot any flaw in my logic.

Thanks so much for all of your helps.

I plan to do the following :

1. Create MyServletContextListener

package org.minh;

import java.io.IOException;

import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import commonj.timers.TimerManager;

/**
 * Servlet implementation class MyServletContextListener
 */
@WebServlet("/MyServletContextListener")
public class MyServletContextListener implements ServletContextListener {
	private static final long serialVersionUID = 1L;
	     
  
	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	

	@Override
	public void contextDestroyed(ServletContextEvent arg0) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void contextInitialized(ServletContextEvent contextEvent){
		// TODO Auto-generated method stub
		
		InitialContext itx = null;
		TimerManager timerManager;
			
				
		
		
		
			
			try {
				itx = new InitialContext ();
				timerManager = (TimerManager) itx.lookup("java:comp/env/timer/TestTimer");
				System.out.println ("Manager is " + timerManager);
				StockQuoteTimerListener stockQuote = new StockQuoteTimerListener("AAA", "[e-mail]");
				
				System.out.println ("===> Stock quote is " + stockQuote);
				
				timerManager.schedule(stockQuote, 1000 * 60);
				
			} catch (NamingException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		
		
		
	
		
		
	}

}

My question is that can i replace the resource ref in the above code with the env-entry ? Please correct me if i am wrong because I think i need the resource refereence to get to the timer instance of the QuoteTimerListener in the code below.

2. Create a stock QuoteTimerListener which is called by the above MyServletContextListener

package org.minh;

import java.io.IOException;
import commonj.timers.Timer;
import commonj.timers.TimerListener;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class StockQuoteTimerListener
 */
@WebServlet("/StockQuoteTimerListener")
public class StockQuoteTimerListener implements TimerListener {
	private static final long serialVersionUID = 1L;
	private String ticker;
	private String email;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public StockQuoteTimerListener(String ticker, String email) {
        super();
        this.ticker = ticker;
        this.email = email;
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	

	@Override
	public void timerExpired(Timer timer) {
		// TODO Auto-generated method stub
		
		System.out.println ("Send ticker to " + this.ticker + "  to email : " + this.email);
		System.out.println ("Timer will run again " + timer.getScheduledExecutionTime());
		
		
	}

}

3. I have the web.xml defined as :

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>Listenering</display-name>
  
 <listener>
		<description>
		</description>
        <display-name>MyServletContextListener</display-name>
        <listener-class>org.emory.MyServletContextListener</listener-class>
	</listener>

<resource-ref>  

        <res-ref-name>timer/TestTimer</res-ref-name>  

         <res-type>commonj.timers.TimerManager</res-type>  

         <res-auth>Container</res-auth>  

         <res-sharing-scope>Shareable</res-sharing-scope>  

   </resource-ref>  
  
  <env-entry>  
        <description>ETS Polling Interval, in milliseconds.</description>  
        <env-entry-name>ets/pollInterval</env-entry-name>  
        <env-entry-type>java.lang.String</env-entry-type>  
        <env-entry-value>600000</env-entry-value>  
    </env-entry>  
  
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
</web-app>

4. and my content.xml is defined as

    <?xml version="1.0" encoding="UTF-8"?>  
    <Context>  
      
        <!-- Default set of monitored resources -->  
        <WatchedResource>WEB-INF/web.xml</WatchedResource>  
      
        <!-- Uncomment this to disable session persistence across Tomcat restarts -->  
        <!--  
        <Manager pathname="" />  
        -->  
      
        <!-- Uncomment this to enable Comet connection tacking (provides events  
             on session expiration as well as webapp lifecycle) -->  
        <!--  
        <Valve className="org.apache.catalina.valves.CometConnectionManagerValve" />  
        -->  
     <Environment name="ets/pollInterval" value="4000000"  
         type="java.lang.String" override="false"/>  


    <Resource name="timer/TestTimer" auth="Container"  
                type="commonj.timers.TimerManager"/>  
    </Context>  

[Tim Holloway]

Actually, we'd prefer that when you switch topics that you start a whole new thread. It makes it easier for people to follow.

As far as I can tell, you are attempting to use the ServletContextListener to invokes functions in a servlet. Only web requests ought to do that. What I'd recommend is that the ServletContextListener construct a separate business object to manage the timer-controlled process. And make it an independent thread. The ServletContextListener (unlike servlets) is allowed to spawn threads.

[Boy Thomas]

I am getting the same error.
context.xml
--------------------
<Environment name="ets/pollInterval" value="4000000"
type="java.lang.String" override="false"/>
<Resource name="timer/TestTimer" auth="Container"
type="commonj.timers.TimerManager"/>

web.xml
--------------------
<resource-ref>
<res-ref-name>timer/TestTimer</res-ref-name>
<res-type>commonj.timers.TimerManager</res-type>
<res-auth>Container</res-auth>
<res-sharing-scope>Shareable</res-sharing-scope>
</resource-ref>
<env-entry>
<description>ETS Polling Interval, in milliseconds.</description>
<env-entry-name>ets/pollInterval</env-entry-name>
<env-entry-type>java.lang.String</env-entry-type>
<env-entry-value>600000</env-entry-value>
</env-entry>

java class
--------------------
InitialContext ic = new InitialContext();
TimerManager tm = (TimerManager)ic.lookup
("java:comp/env/timer/TestTimer");
// Execute timer every 10 seconds starting immediately
tm.schedule (new MyTimerListener(), 0, 10*1000);
out.println("<h4>Timer scheduled!</h4>");

Any help is greatly appreciated.