ContextListener

[Nabila Mohammad]

Hi!


I unable to run this simple program mentioned in HFSJ and cant figure out the mistake.
I keep getting the 404 resource not found error.

MyServletContextListener

package com.example;

import javax.servlet.*;
import javax.servlet.http.*;


class MyServletContextListener implements ServletContextListener

{

public void contextInitialized(ServletContextEvent e)
{
ServletContext sc=e.getServletContext();
String dogBreed=sc.getInitParameter("breed");
Dog d = new Dog(dogBreed);
sc.setAttribute("dog",d);

}



public void contextDestroyed(ServletContextEvent e)
{



}


}
    

ListenerTester.java

package com.example;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import com.example.Dog;


public class ListenerTester extends HttpServlet
{


public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{


response.setContentType("text/html");
PrintWriter out= response.getWriter();

out.println("Testing Context ATtributes set by Listener");
out.println("<br>");


Dog dog=(Dog) getServletContext().getAttribute("dog");
out.println("Dog's breed is" + dog.getBreed());

}
}    

Dog,java

    package com.example;



public class Dog
{

String breed;

public Dog(String breed)
{
this.breed=breed;
}

public String getBreed()
{
return breed;
}



}

web.xml

<web-app xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org./2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
version="2.4">


<servlet>
<servlet-name>ListenerTester</servlet-name>
<servlet-class>com.example.ListenerTester</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>ListenerTester</servlet-name>
<url-pattern>ListenTest.do</url-pattern>
</servlet-mapping>


<context-param>
<param-name>breed</param-name>
<param-value>My Little Poodle</param-value>
</context-param>


<listener>
<listener-class>
com.example.MyServletContextListener
</listener-class>
</listener>


</web-app>




    

[Ankit Garg]

Your application's deployment is failing. The url-pattern in web.xml must start with / so this line is creating the problem

<url-pattern>ListenTest.do</url-pattern>

[Bindu Lakhanpal]

Ankit Garg wrote:The url-pattern in web.xml must start with /

unless its an extension match(*.do) which must start with a * and not a /.

[Sai Surya]

Hi Nabila,

Can you post your JSP code here, I wanted to check how you are calling the servlet from JSP?

[Nabila Mohammad]

Hi there!


I am not using JSP . Just using servlets, exactly the way it is mentioned in HFSJ.
I had tried the same program earlier and it was perfectly fine. It is still running.. but some how this
one isn't !

I thought by adding "/"in <url-pattern>/ListenTest.do</url-pattern> , it should work , but its still giving me the same error.

[Nabila Mohammad]

My log.. if it's any help.

Sep 28, 2009 4:19:43 PM org.apache.coyote.http11.Http11BaseProtocol pause
INFO: Pausing Coyote HTTP/1.1 on http-8080
Sep 28, 2009 4:19:44 PM org.apache.catalina.core.StandardService stop
INFO: Stopping service Catalina
Sep 28, 2009 4:19:44 PM org.apache.coyote.http11.Http11BaseProtocol destroy
INFO: Stopping Coyote HTTP/1.1 on http-8080
Sep 28, 2009 4:19:45 PM org.apache.catalina.core.AprLifecycleListener lifecycleEvent
INFO: Failed shutdown of Apache Portable Runtime
Sep 28, 2009 4:19:51 PM org.apache.catalina.core.AprLifecycleListener lifecycleEvent
INFO: The Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: C:\Program Files\Apache Software Foundation\Tomcat 5.5\bin;.;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;c:\Perl\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\Program Files\Attachmate\E!E2K\;C:\j2sdk1.4.2_07;C:\Program Files\Java\jdk1.5.0_15\bin; ;C:\Program Files\QuickTime\QTSystem\
Sep 28, 2009 4:19:51 PM org.apache.coyote.http11.Http11BaseProtocol init
INFO: Initializing Coyote HTTP/1.1 on http-8080
Sep 28, 2009 4:19:51 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 593 ms
Sep 28, 2009 4:19:51 PM org.apache.catalina.core.StandardService start
INFO: Starting service Catalina
Sep 28, 2009 4:19:51 PM org.apache.catalina.core.StandardEngine start
INFO: Starting Servlet Engine: Apache Tomcat/5.5.27
Sep 28, 2009 4:19:51 PM org.apache.catalina.core.StandardHost start
INFO: XML validation disabled
Sep 28, 2009 4:19:52 PM org.apache.catalina.core.StandardContext start
SEVERE: Error listenerStart
Sep 28, 2009 4:19:52 PM org.apache.catalina.core.StandardContext start
SEVERE: Context [/ContextListener] startup failed due to previous errors
Sep 28, 2009 4:19:53 PM org.apache.tomcat.util.digester.Digester fatalError
SEVERE: Parse Fatal Error at line 1 column 1: The markup declarations contained or pointed to by the document type declaration must be well-formed.
org.xml.sax.SAXParseException: The markup declarations contained or pointed to by the document type declaration must be well-formed.
	at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(Unknown Source)
	at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.fatalError(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLScanner.reportFatalError(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDTDScannerImpl.scanDecls(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDTDScannerImpl.scanDTDExternalSubset(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.dispatch(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.next(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
	at org.apache.tomcat.util.digester.Digester.parse(Digester.java:1562)
	at org.apache.catalina.startup.TldConfig.tldScanStream(TldConfig.java:514)
	at org.apache.catalina.startup.TldConfig.tldScanTld(TldConfig.java:553)
	at org.apache.catalina.startup.TldConfig.execute(TldConfig.java:301)
	at org.apache.catalina.core.StandardContext.processTlds(StandardContext.java:4307)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4144)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:760)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:740)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:544)
	at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:927)
	at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:890)
	at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)
	at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1150)
	at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:120)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1022)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:736)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:448)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:700)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:552)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:295)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:433)
Sep 28, 2009 4:19:53 PM org.apache.catalina.core.StandardContext processTlds
SEVERE: Error reading tld listeners javax.servlet.ServletException: Exception processing TLD at resource path /WEB-INF/SelectTag.tld in context /Select
javax.servlet.ServletException: Exception processing TLD at resource path /WEB-INF/SelectTag.tld in context /Select
	at org.apache.catalina.startup.TldConfig.tldScanTld(TldConfig.java:555)
	at org.apache.catalina.startup.TldConfig.execute(TldConfig.java:301)
	at org.apache.catalina.core.StandardContext.processTlds(StandardContext.java:4307)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4144)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:760)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:740)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:544)
	at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:927)
	at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:890)
	at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)
	at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1150)
	at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:120)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1022)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:736)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:448)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:700)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:552)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:295)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:433)
Sep 28, 2009 4:19:54 PM org.apache.coyote.http11.Http11BaseProtocol start
INFO: Starting Coyote HTTP/1.1 on http-8080
Sep 28, 2009 4:19:54 PM org.apache.jk.common.ChannelSocket init
INFO: JK: ajp13 listening on /0.0.0.0:8009
Sep 28, 2009 4:19:54 PM org.apache.jk.server.JkMain start
INFO: Jk running ID=0 time=0/31  config=null
Sep 28, 2009 4:19:54 PM org.apache.catalina.storeconfig.StoreLoader load
INFO: Find registry server-registry.xml at classpath resource
Sep 28, 2009 4:19:54 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 2907 ms
  

[Christophe Verré]

Exception processing TLD at resource path /WEB-INF/SelectTag.tld in context /Select

It may help to see SelectTag.tld.

[Nabila Mohammad]

I noticed that, but I don't have any selecttag.tld file I am not even using any tld or jsp files.I have mentioned all the files I am using...

[Vijitha Kumara]

Nabila Mohammad wrote:I noticed that, but I don't have any selecttag.tld file I am not even using any tld or jsp files.I have mentioned all the files I am using...

Your context name is "Select" ? Then you will have to check the contents inside your application in the container.

[Chinmaya Chowdary]

Hi Nabila.

Use

    public class MyServletContextListener implements ServletContextListener

[Nabila Mohammad]

Chinmaya, aren't I using the same thing...

[Ankit Garg]

Nabila Mohammad wrote:Chinmaya, aren't I using the same thing...

Your listener class is not public. Why couldn't I see that

[Nabila Mohammad]

Thanks Chinmaya, Good Catch!!

These tiny mistakes can really drive you crazy!

Thanks ppl for all your help..

[Sai Surya]

However, I am trying to understand the relationship between the exception and the not defining listener class public.

[Christophe Verré]

Sai Surya wrote:However, I am trying to understand the relationship between the exception and the not defining listener class public.

I'd like to know that too.

[Bahman Robin]

Hi all,
I saw this old post that shows exactly my recent problem. I have the same problem and I understand nobody answered it.
On the server log I got the same message which is on the line 22 (error ListenerStart) of server log in this post.
I appreciate your prompt solution for this problem.

[Frits Walraven]

Hi Bahman,

Could you start a new thread with this question (please do not wake up old threads) and add some more information of your setup.
(this old post was about not having a public Listener class)

Regards,
Frits