Michał Wróbel's blog

Software engineering blog

Posts Tagged ‘tomcat’

How to configure Eclipse to debug Alfresco java webscript code

How to configure Eclipse to debug Alfresco java webscript code

NOTE: It is assumed, that Eclipse environment has been configured to work with Alfresco SDK. If it’s not true the configuration process has been described here: http://wiki.alfresco.com/wiki/Alfresco_SDK_3.4#Set_Eclipse_Compiler_Compliance_Level_to_6.0.

1. Select: Run menu -> Debug configurations…
2. Create new configuration for ‘Remote Java Application’
3. In ‘Project’ field select ‘home’ project (presumably your webscript project), which you want to debug (but it is also possible to debug code from Alfresco core outside selected project)
4. In ‘Connection properties’ set Tomcat server IP address and debug port you defined earlier.

NOTE: It’s advised against to use ‘localhost’ instead of IP address on Windows because of hosts file issues.

5. Click Apply, Debug
6. If everything went correct you shouldn’t get any message.
7. Switch to debug perspective
8. You should see something like this:

Proper screen from eclipse debug perspective

Proper screen from eclipse debug perspective


In case of debug session disconnection (eg. Tomcat restart) you may reconnect to it using Relaunch option:
Reconnecting to debugger

Reconnecting to debugger


9. Now you can normally set breakpoints and trace code execution of your webscript or other Alfresco SDK projects. A good test is setting a breakpoint in org.alfresco.web.bean.LoginBean at line
“FacesContext context = FacesContext.getCurrentInstance();” – breakpoint should be caught at Alfresco Explorer login attemp.

NOTE: You may get following error message: “Unable to install breakpoint in org.evolpe.webscripts.XMLwebs due to missing line number attributes. Modify compiler options to generate line number attributes.
Reason:
Absent Line Number Information”

Missing line info window

Missing line info window

CAUSE&SOLUTION: To debug your own webscripts or other code it’s essential to enable code line number information in the compiler. If you use ant, set debug=”true’ parameter in javac task.

How to configure tomcat to debug instance of Alfresco on Windows and Linux will be described soon in my next articles.;)

Tomcat uses wrong path although CATALINA_HOME and CATALINA_BASE have correct values.

The cause of the problem may be that your web application uses tomcat6.exe instead of catalina.bat to start up.  From my observations it seems tomcat6.exe as opposed to catalina.bat uses environment variables only for the 1st run to copy CATALINA_HOME and CATALINA_BASE values to Windows Registry. Thereafter these parameters start to live on their own;) I had one instance of Tomcat for my Openbravo developer stack and the other for Alfresco. Tomcat6.exe used old values regardless of completly separate instalation of Alfresco dev stack.
You can edit these and other variables directly via Windows Registry editor, the path is:

HKLM/SOFTWARE/Apache Software Foundation/…..

or more conveniently you can use tomcat6w.exe GUI:

tomcat6w //ES//<serviceName> (eg. tomcat6w //ES//alfrescoTomcat)

calls a neat window where you can edit variables you need to run your web app properly.

there’s also //MS// parameter which will call a simple application monitoring given service:

tomcat6w //MS//<serviceName>

If you want to read more about running Tomcat as Windows service with tomcat6.exe go to an article from Apache Tomcat documentation.

Hope this helps someone:)

I get NoClassDefFound for ContextLoaderListener class using Spring and Eclipse IAM Maven plugin

My most common headache during my last Spring project was:


java.lang.ClassNotFoundException: org.springframework.web.context.ContextLoaderListener

during start of Tomcat.

Every source pointed to problems with spring.jar, so I suspected having some version conflict between my Spring libraries (eg. I used also Spring-WS in an old version). But that wasn’t real cause and I’d wasted a lot of time. The real problem was faulty Eclipse IAM plugin.

Try out some tricks I’ve described in my another article : Problems using Eclipse IAM and Maven

They really may help you.

Problems using Eclipse IAM and Maven

During my last project I was involved, I used Eclipse IAM plugin for integration with Maven. It caused many problems, mainly Class not found exceptions and issues with Tomcat server.

Generally I perceived that Eclipse IAM tends to lose jars from pom.xml, what leads to unexpected, bizarre time wasting NoClassDefFoundError.

Unfortunately I hadn’t been sucessful in finding causes of my problems but I’d like to share with you my standard ‘IAM problems checklist’ 😉

If you have any problems try this (in specified order) :

  1. Use refresh, then fetch source jars option from maven menu.
  2. Try cleaning maven libraries, then do ‘1.’
  3. After doing ‘2.’, remove your app from Tomcat, clean server, then deploy again.
  4. Try removing whole server, then add it again.
  5. REMOVE AND REGENERATE WHOLE WORKSPACE

Any step mentioned above is not a joke. I had really to ‘reset’ workspace a few times to make things work again.. First three steps helped me in 80% cases.

I hope my tips will save your time.

How to capture content of eclipse Console window (web tomcat application)?

The console window in eclipse has rather short ‘history’ and surprisingly the tomcat log file doesn’t appear anywhere on the hardrive when you run your application directly from eclipse. (Or it is situated in some mysterious place) It took me some time to find an option allowing to capture the content of console window to a given file.

The solution :

Run menu – > Run configurations… – ><your tomcat server > – > common – > Standard input and output

Tick the option ‘file’ and type path to your log file.

Subscribe by mail