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Why my Tomcat 7 stop working after deploy

I have a grails app that runs on dev environment and I crated the war without problems.
In the server, I stop the service using "sudo service tomcat7 stop" command and put the war file into the server folder "/var/lib/tomcat7/webapps" and start the server again with the command "sudo service tomcat7 start".
For checking the state of the server I run "sudo service tomcat7 status" and get the "Tomcat servlet engine is running with pid 19169" response, and check if the application deploys correctly on the folder "/var/lib/tomcat7/webapps" and I see the project's folder there.
Right now, if I check the catalina.out file, I can't see any deploy error having this:
May 27, 2020 9:04:31 PM org.apache.coyote.AbstractProtocol init INFO:
Initializing ProtocolHandler ["http-bio-80"] May 27, 2020 9:04:31 PM
org.apache.catalina.startup.Catalina load INFO: Initialization
processed in 1280 ms May 27, 2020 9:04:31 PM
org.apache.catalina.core.StandardService startInternal INFO: Starting
service Catalina May 27, 2020 9:04:31 PM
org.apache.catalina.core.StandardEngine startInternal INFO: Starting
Servlet Engine: Apache Tomcat/7.0.26 May 27, 2020 9:04:33 PM
org.apache.catalina.startup.HostConfig deployDescriptor INFO:
Deploying configuration descriptor
/etc/tomcat7/Catalina/localhost/docs.xml May 27, 2020 9:04:33 PM
org.apache.catalina.startup.HostConfig deployDescriptor INFO:
Deploying configuration descriptor
/etc/tomcat7/Catalina/localhost/host-manager.xml May 27, 2020 9:04:33
PM org.apache.catalina.startup.HostConfig deployDescriptor INFO:
Deploying configuration descriptor
/etc/tomcat7/Catalina/localhost/manager.xml May 27, 2020 9:04:33 PM
org.apache.catalina.startup.HostConfig deployDescriptor INFO:
Deploying configuration descriptor
/etc/tomcat7/Catalina/localhost/examples.xml May 27, 2020 9:04:33 PM
org.apache.catalina.startup.HostConfig deployWAR INFO: Deploying web
application archive /var/lib/tomcat7/webapps/fleetcontroller.war
log4j:WARN No appenders could be found for logger
(net.bull.javamelody). log4j:WARN Please initialize the log4j system
properly. log4j:WARN See
http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
But if I wait a while, the tomcat service is stoped.
When I check the server status with "sudo service tomcat7 status" I get this msg
Tomcat servlet engine is not running, but pid file exists.
And the catalina.out show me:
WARN intercept.RequestmapFilterInvocationDefinition - Exception
initializing; this is ok if it's at startup and due to GORM not being
initialized yet since the first web request will re-initialize. Error
message is: {0} 2020-05-27 21:14:13,192 [pool-2-thread-1] WARN
module.ModuleDeclarationsFactory - resources artefact
KickstartResources does not define any modules | Using LESS files to
generating CSS files!
Please, if someone can help with that, because I don't know how to find the problem.
Really thanks for your time.

It was a virtual machine size problem.
I checked some server parameters and see that they was lower than production. infrastructure office changed the virtual server size and it starts to work!
Thanks you for your time!

Cannot run JAX-WS Java Web Service on Apache Tomcat

Summary
I've been tasked to write a Java web service to integrate two disparate systems in our enterprise environment. Since I'm actually an experienced C#.NET MVC developer and only consider myself intermediate at Java, I began by searching for "Java Web Service Tutorials". I am trying to run this common tutorial, but I'm unable to run the tutorial service due to an HTTP 404 error.
Process
I'm using the Java Web Application template in Netbeans 8.0.2. I used JDK 1.6.0.25 to compile the tutorial (since the eventual service I need to write will need this Java version to be compatible with some other JARs I'll be using). Everything compiles to a WAR file just fine.
I then deployed the WAR file by loading the server's Tomcat Manager GUI and using the WAR file to deploy feature. When I do so, the WAR file is copied, and the application starts. However, when I attempt to access the service via the link "http://localhost:8080/HelloWorld/hello" from the tutorial, the service returns a 404 error.
Server Environment
Oracle Enterprise Linux distro, version 3.8.13-44.1.1.el6uek.x86_64
Apache Tomcat 6.0.24
JVM 1.7.0_75-mockbuild_2015_01_20_16_42-b00
If the advice is that I need to change the Java or Tomcat versions or platforms, I need to know that as well since I have little experience with these technologies. However, I may not be able to change all the factors due to limitations with my Linux distro (per my server admin).
Things I've tried (in order):
Setup a Local Tomcat Server on Windows
I installed a local Tomcat Server on my Windows 7 laptop. Since the Linux server is running Java 1.7.0.75, I installed a matching Windows version of JRE 1.7.0.75 from Oracle's support page. I then downloaded Apache Tomcat 6.0.24 Windows Service from their archives and installed it successfully, using the JRE 1.7.0.75 and local port 1985 (to separate it from the GlassFish local server used within Netbeans).
Just as on the Linux server, my local Tomcat server couldn't start the tutorial. Manually clicking the start command link gives me the message "FAIL - Application at context path /com.mkyong.ws could not be started". My local server's logs don't show anything about that application failing to start either.
Adding JAX-WS RI JAR files to {$Tomcat}/lib
Per section 5 on the tutorial mentioned above, I then added the indicated JAR files to the server's {$Tomcat}/lib folder and restarted the server. This time, the application started, but I still couldn't access the service. The link "http://localhost:8080/HelloWorld/hello" from the tutorial returns a 404 error. I even tried copying the entire JAX-WS RI/lib folder to the {$Tomcat}/lib directory with no changes, so I backed out this change.
For reference, here's a list of the files I've copied:
gmbal-api-only.jar
ha-api.jar
jaxb-core.jar
jaxb-impl.jar
jaxws-api.jar
jaxws-rt.jar
management-api.jar
policy.jar
stax-ex.jar
streambuffer.jar
Enabling DEBUG mode in the local Tomcat Server
I un-deployed the WAR file. Using the Apache Tomcat Monitor, I stopped the service, deleted the existing logs, enabled the DEBUG logging level, and restarted the service. I then re-deployed the tutorial WAR file. I again saw it didn't start, and then I opened all the log files. There is not even a mention of the failure to access the service, but perhaps 404 errors aren't logged.
Running the service using the Netbeans-embedded Glassfish server
When I first created the Web Application, Netbeans offered to set me up with a local Glassfish server. I accepted, and I set everything up with defaults. When I try to run the tutorial against this server, I cannot access the service. The link "http://localhost:8080/HelloWorld/hello" from the tutorial still returns a 404 error.
Researching other posts and tutorials
Here are some other StackOverflow posts and websites I've reviewed without finding a resolution:
JAX-WS on Tomcat server (doesn't apply)
Deploying JAX-WS webservice as War in Apache Tomcat (similar to the tutorial in recommending to copy the extra JAR files)
JAX-RPC / JAX-WS runtime in Apache Tomcat (just informational)
how to deploy a jax-ws service to eclipse or tomcat? (similar to the tutorial in recommending to copy the extra JAR files)
https://myarch.com/create-jax-ws-service-in-5-minutes/ (similar to the tutorial but without deployment help)
Questions I'm Pondering
Is there something wrong with the code in the tutorial? (Doesn't seem likely since from the comments others have had success.)
Is there a significant difference in the versions of Java or Tomcat he's using in the tutorial? (He doesn't give an versions of Java or Tomcat.)
Should I run local Tomcat against a JDK instead of a JRE?
Should the tutorial be compiled against the same JDK as Tomcat is using? (I hope not as this would seem very limiting...)
Can I even run JAX-WS in Tomcat? (Based on pages like http://tomee.apache.org/apache-tomee.html, it seems like the base TOmcat might not even support JAX-WS? Again, just my limited experience.)
I'd appreciate any troubleshooting guidance anyone can offer. Thank you in advance for the help!
UPDATE #1
Per the request of #NIKETBHANDARY, I stopped the service, deleted the logs, restarted the service, and browsed in Chrome to localhost:1985/helloworld/hello - still getting the 404 error. I then opened the catalina.log file, but it's completely empty. Only jakarta_service.log has any log entries, and all are about the service starting. I also verified that the logging level is set to debug. What else can I change to get additional log messages?
I also ran a search for "com.mkyong" in the entire Tomcat directory. Only the webapp WAR file, webapps/../META-INF/context.xml, webapps/../WEB-INF/sun-jaxws.xml, and /conf/cataline/localhost/com.mkyong.we.xml files returned any hits. Nothing in any logs. Could that indicate that this is a configuration problem?
UPDATE #2
Apparently, Tomcat doesn't flush its log messages fully until the thread closes as the service shuts down (probably due to the logging configuration). As such, I stopped the service which flushed the log files. Here's the entire contents of the catalina.log file (which does contain a reference to com.mkyong):
Aug 17, 2015 9:51:17 PM org.apache.catalina.core.AprLifecycleListener init
INFO: Loaded APR based Apache Tomcat Native library 1.1.19.
Aug 17, 2015 9:51:17 PM org.apache.catalina.core.AprLifecycleListener init
INFO: APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].
Aug 17, 2015 9:51:19 PM org.apache.coyote.http11.Http11AprProtocol init
INFO: Initializing Coyote HTTP/1.1 on http-1985
Aug 17, 2015 9:51:19 PM org.apache.coyote.ajp.AjpAprProtocol init
INFO: Initializing Coyote AJP/1.3 on ajp-8009
Aug 17, 2015 9:51:19 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 2121 ms
Aug 17, 2015 9:51:19 PM org.apache.catalina.core.StandardService start
INFO: Starting service Catalina
Aug 17, 2015 9:51:19 PM org.apache.catalina.core.StandardEngine start
INFO: Starting Servlet Engine: Apache Tomcat/6.0.24
Aug 17, 2015 9:51:19 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deploying configuration descriptor com.mkyong.ws.xml
Aug 17, 2015 9:51:20 PM com.sun.xml.ws.transport.http.servlet.WSServletContextListener contextInitialized
INFO: WSSERVLET12: JAX-WS context listener initializing
Aug 17, 2015 9:51:22 PM com.sun.xml.ws.transport.http.servlet.WSServletDelegate <init>
INFO: WSSERVLET14: JAX-WS servlet initializing
Aug 17, 2015 9:51:22 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deploying configuration descriptor host-manager.xml
Aug 17, 2015 9:51:22 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deploying configuration descriptor manager.xml
Aug 17, 2015 9:51:22 PM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deploying web application directory docs
Aug 17, 2015 9:51:22 PM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deploying web application directory examples
Aug 17, 2015 9:51:22 PM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deploying web application directory ROOT
Aug 17, 2015 9:51:22 PM org.apache.coyote.http11.Http11AprProtocol start
INFO: Starting Coyote HTTP/1.1 on http-1985
Aug 17, 2015 9:51:22 PM org.apache.coyote.ajp.AjpAprProtocol start
INFO: Starting Coyote AJP/1.3 on ajp-8009
Aug 17, 2015 9:51:22 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 3895 ms
UPDATE #3
I'm becoming more convinced there's a configuration problem somewhere. On a hunch, I studied and installed Apache TomEE 1.7.2 for Windows, pointing to the same JRE as the regular Tomcat. After studying the running.txt file and experimenting with the properties and settings, I was finally able launch a local version of TomEE. I deployed the same WAR file as before, and I found it would not load the WAR application due to the following error:
java.lang.ClassNotFoundException: com.sun.xml.ws.transport.http.servlet.WSServletContextListener
Googling that error led (again) to MKYong's blog for a fix (copy the jaxws-rt.jar file to the {$tomcat}/lib folder. I redeployed the WAR file, and the manager loaded the application. HOWEVER, just like on regular Tomcat, the URL "http://localhost:8080/HelloWorld/hello" from the tutorial still returns a 404 error. So, the results are exactly the same.
Short of compiling the tutorial against other versions of JDK, I'm running out of ideas quickly... :-)
UPDATE #4
Per another request below, here's a list of all JAR files in the {$Tomcat}\lib folder:
annotations-api.jar
catalina.jar
catalina-ant.jar
catalina-ha.jar
catalina-tribes.jar
el-api.jar
gmbal-api-only.jar
ha-api.jar
jasper.jar
jasper-el.jar
jasper-jdt.jar
jaxb-core.jar
jaxb-impl.jar
jaxws-api.jar
jaxws-rt.jar
jsp-api.jar
management-api.jar
policy.jar
servlet-api.jar
stax-ex.jar
streambuffer.jar
tomcat-coyote.jar
tomcat-dbcp.jar
tomcat-i18n-es.jar
tomcat-i18n-fr.jar
tomcat-i18n-ja.jar
The {$Tomcat}\webapps folder contains the following:
..\com.mkyong.ws
..\docs
..\examples
..\host-manager
..\manager
..\ROOT
..\com.mkyong.ws.war
Update #5
The {$Tomcat}\webapps\com.mkyong.ws directory contains the following:
Here's a screenshot of the Tomcat Manager GUI:
Here's a screenshot of the HTTP 404 error I'm receiving along with the URL:
I've also confirmed that the files in the WAR exactly match the tutorial.

There is problem in deployment of your ws module.
U have just copied the whole folder from the MKyoung sample.
I doesn't work that way around.
Not only that now display all the folders and files structure inside the ws module delete the rest of the modules from your post.I wanted only the structure of ws module.
The module name has to sample instead of com.mkyoung.ws
and the structure for it has to be
**sample**
------WEB-INF
------index.jsp
WEB-INF
----classes
----web.xml
----sun-jaxws.xml
classes
----com
--------mkyoung
-----------ws
ws
-----Helloworld.class
-----HeloworldIMPL.class

#NIKETBHANDARY helped me understand what was wrong and how to quickly correct it. I'd also like to post exactly what I did wrong and how I fixed it permanently so that future coders can benefit from my five-day experience. :-)
When I originally built the tutorial using Netbeans, I used the Java Web --> Web Application template (which is available after installing the Java EE Base plugin accessible through Netbeans --> Tools --> Plugins):
I built all the files exactly per the tutorial, but I failed to really read through step #5, especially this line:
<jar jarfile="${dist}/war/HelloWorld-${DSTAMP}.war" basedir="${dist}/war/build/"/>
After further review, I found that the build script was producing a WAR file called HelloWorld.war. Then, when that file was deployed to Tomcat, the web application was called HelloWorld in the Tomcat Manager. That's why the service endpoint was set to http://localhost:8080/HelloWorld/hello. The "HelloWorld" is literally the name of the Tomcat application, and the "/hello" part corresponds with the endpoint from the sun-jaxws.xml file. (Looking back, it makes total sense given typical web hosting organization. IIS pretty much works the same way.)
So, to fix the problem, I needed to modify the Netbeans project to produce a WAR file named HelloWorld.war. In the tutorial, he includes an actual Ant build script. In this case, I needed to take these steps:
Right-click on the project in the Netbeans Project Explorer.
Choose Properties.
Click on the Build --> Packaging category.
Set the WAR file field to HelloWorld.war.
Here is a screenshot:
Once that was done, I created a new build, deployed to my local Tomcat server, and everything worked as expected. I was also able to deploy the WAR file to my Linux server and test it successfully. Problem solved! :-)

FAIL - Application at context path /Appcould not be started by Tomcat Manager 6

I was trying to deploy a war file via tomcat manager 6. Once deployed get always the same
error :
FAIL - Application at context path /App could not be started
The war file is under apache-tomcat-6.0.0/webapps folder.
I was googling and tried different options like :
removing apache-tomcat-6.0.0/work/Catalina/localhost folder and also apache-tomcat-6.0.0/webapps/App
restarting the server and redeploying again.
As I could see in the catalinalog file :
INFO: Deploying web application archive App.war
3:32:47 PM org.apache.catalina.core.StandardContext start
SEVERE: Error listenerStart
2012 3:32:47 PM org.apache.catalina.core.StandardContext start
SEVERE: Context [/App] startup failed due to previous errors
2012 3:32:50 PM org.apache.catalina.core.StandardContext start
SEVERE: Error listenerStart
2012 3:32:50 PM org.apache.catalina.core.StandardContext start
SEVERE: Context [/App] startup failed due to previous errors
Any ideas ?

Add a “log4j.properties” file under ‘/WEB-INF/classes’ directory inside your WAR to help debug which one of the listeners is throwing this error.
This holds true for Tomcat versions < 6.0
In Tomcat 6 or above, the default logger is the”java.util.logging” logger and not Log4J. So if you are trying to add a “log4j.properties” file – this will NOT work. The Java utils logger looks for a file called “logging.properties” as stated here:
http://tomcat.apache.org/tomcat-6.0-doc/logging.html
So to get to the debugging details create a “logging.properties” file under your”/WEB-INF/classes” folder of your WAR and you’re all set.
And now when you restart your Tomcat, you will see all of your debugging in it’s full glory!!!
Sample logging.properties file:
org.apache.catalina.core.ContainerBase.[Catalina].level = INFO
org.apache.catalina.core.ContainerBase.[Catalina].handlers = java.util.logging.ConsoleHandler
and you will most likely see a “ClassNotFound” exception.

Create web service using Eclipse

I am trying to create my first webservice using eclipse javaEE under Axis2,
i am following this turorial eclipse tutorial
to learn how to make it.I make the webservice but when i want to assure that the ws has been deployed through viewing it through URL, an HTTP status 400 occure. How can I know what is the error??
here what i make exactly:
i make the settings in preferences [ ant , axis2, tomcat and java ].
New -> New dynamic web page
new ->java (I create the class i want to convert to ws)
new ->web service (i want to create bottom up ws).
type http://localhost:8080/Axis2/services/listservices in the url of browser
this what return HTTP Status 404 - /services/listservices
can some one tell me how can i know what is the error? or how can i define it?
EDIT:
an exception happen in the console of eclipse which is :
org.apache.axis2.transport.http.AxisAdminServlet java.lang.ClassNotFoundException: org.apache.axis2.transport.http.AxisAdminServlet
what should I do ,in the configuration i specify where is axis2 and eclipse shows
Axis2 runtime loaded successfully
after creating new work space and create webservice again, this is the output appears in console
Dec 20, 2010 8:32:04 PM org.apache.catalina.core.AprLifecycleListener init
INFO: The APR based Apache Tomcat Native library which allows optimal performance in
production environments was not found on the java.library.path: C:\Program
Files\Java\jdk1.6.0_18\bin;.;C:\Windows\Sun\Java\bin;C:\Windows\system32;C:\Windows;F:/alaa college/year 4/1st
semester/Advance sw/Libraries/eclipse/jre/bin/client;F:/alaa college/year 4/1st
semester/Advance sw/Libraries/eclipse/jre/bin;D:\app\AloOoSh\product\11.1.0\db_1\bin;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files\Java\jdk1.6.0_18\bin;%ANT_HOME%\bin;%AXIS2_HOME%\bin;%CATALINA_HOME%\bin;C:\Program Files\MATLAB\R2008a\bin;C:\Program Files\MATLAB\R2008a\bin\win32;
Dec 20, 2010 8:32:05 PM org.apache.tomcat.util.digester.SetPropertiesRule begin
WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source'
to 'org.eclipse.jst.jee.server:testFirst' did not find a matching property.
Dec 20, 2010 8:32:05 PM org.apache.coyote.http11.Http11Protocol init
INFO: Initializing Coyote HTTP/1.1 on http-8080
Dec 20, 2010 8:32:05 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 401 ms
Dec 20, 2010 8:32:05 PM org.apache.catalina.core.StandardService start
INFO: Starting service Catalina
Dec 20, 2010 8:32:05 PM org.apache.catalina.core.StandardEngine start
INFO: Starting Servlet Engine: Apache Tomcat/6.0.29
[INFO] Deploying module: addressing-1.4 - file:/D:/EclipseExcercises/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/testF
irst/WEB-INF/modules/addressing-1.4.mar
[INFO] Deploying module: metadataExchange-1.4 -
file:/D:/EclipseExcercises/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/testFirst/WEB-INF/modules/mex-1.4.mar
[INFO] Deploying module: ping-1.4 -
file:/D:/EclipseExcercises/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/testFirst/WEB-INF/modules/ping-1.4.mar
[INFO] Deploying module: script-1.4 - file:/D:/EclipseExcercises/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/testFirst/WEB-INF/modules/scripting-1.4.mar
[INFO] Deploying module: smtpfault - file:/D:/EclipseExcercises/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/testFirst/WEB-INF/modules/smtpfault.mar
[INFO] Deploying module: soapmonitor-1.4 - file:/D:/EclipseExcercises/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/testFirst/WEB-INF/modules/soapmonitor-1.4.mar
[INFO] Deploying Web service: Converter - file:/D:/EclipseExcercises/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/testFirst/WEB-INF/services/Converter/
[INFO] Deploying Web service: version.aar - file:/D:/EclipseExcercises/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/testFirst/WEB-INF/services/version.aar
Dec 20, 2010 8:32:06 PM org.apache.coyote.http11.Http11Protocol start
INFO: Starting Coyote HTTP/1.1 on http-8080
Dec 20, 2010 8:32:06 PM org.apache.jk.common.ChannelSocket init
INFO: JK: ajp13 listening on /0.0.0.0:8009
Dec 20, 2010 8:32:06 PM org.apache.jk.server.JkMain start
INFO: Jk running ID=0 time=0/19 config=null
Dec 20, 2010 8:32:06 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 1383 ms

These is my own post to creating webservice and use that service in android. its
work properly.
Try this once below link
http://lukencode.com/2010/04/27/calling-web-services-in-android-using-httpclient/#comment-179

The 404 error occurs because there is nothing at the desired url. So there must have been something wrong with your deployment.
Have you set up a server in eclipse and actually published the WS at all? Note that this is different from running Tomcat from a directory somewhere else on your computer! You can add a server instance by selecting New => Server.
If the server configuration is otherwise correct, the server output should appear in eclipse's console, and if anything is wrong with your WS setup, there should be error messages you can use to track down the problem.

You probably extracted the contents of axis2.war (renamed to app.zip) into the wrong folder or deployed files to the wrong folder. Look for the WEB-INF folder directly under the app.war folder that you deployed. If you have another folder of WEB-INF for the axis2 extracted folders, then JBoss cannot locate them. The WEB-INF folder must be a folder as a 1st level descendant. Along with the following folders: axis2-web, META-INF and org.

Tomcat 6 server - was running, but now it won't start - error in log file -SEVERE: Null component?

I've been running Tomcat 6 on my pc for some time now, and it has been running successfully...up until today. I just tried to start it, and now for some reason it won't start.
I start it from a command line prompt. The second prompt that appears after I enter 'startup' in the first prompt is exiting quickly, whereas it usually stays open and shows the status of the server.
Here's what the log file logged -
Dec 3, 2010 4:00:00 PM org.apache.catalina.core.AprLifecycleListener init
INFO: The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: C:\Java\jdk1.5.0_16\bin;.;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\system32\WindowsPowerShell\v1.0;c:\Program Files\Common Files\Roxio Shared\DLLShared\;C:\Java\jdk1.5.0_16\bin;C:\jakarta-tomcat\bin;C:\MYSQL\MySQL Server 5.1\bin
Dec 3, 2010 4:00:01 PM org.apache.coyote.http11.Http11Protocol init
INFO: Initializing Coyote HTTP/1.1 on http-8080
Dec 3, 2010 4:00:01 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 424 ms
Dec 3, 2010 4:00:01 PM org.apache.catalina.core.StandardService start
INFO: Starting service Catalina
Dec 3, 2010 4:00:01 PM org.apache.catalina.core.StandardEngine start
INFO: Starting Servlet Engine: Apache Tomcat/6.0.29
Dec 3, 2010 4:00:01 PM org.apache.tomcat.util.modeler.Registry registerComponent
SEVERE: Null component Catalina:type=JspMonitor,name=jsp,WebModule=//localhost/MyWebApp,J2EEApplication=none,J2EEServer=none
I never saw this before, where it says SEVERE: Null component... - what does it mean? What's causing it?

Here's what I ended up doing. I made a backup of my server.xml and web.xml files, along with my apps under the webapps folder, and removed jakarta-tomcat, and then reinstalled it. I restored the server.xml and web.xml file, threw my webapps back in, and started Tomcat up. This time, I got the same error as before, but it pinpointed that a particular servlet under one of my folders had a "bad version number". So I went through my servlet folders and recompiled the classes.
I started Tomcat again, and its running as it used to.
The problem was that a class had been compiled under a different version of the JDK, and it was causing an error.

Have you changed anything recently with regard to your Tomcat installation, configuration or deployments? Do you have a web application running under Tomcat called "MyWebApp"? If so, I would remove it and see if that fixes the problem. Otherwise, you might have to reinstall Tomcat.