I'm hitting the same problem described in here, but I don't know my websphere version at the time
More questions
1) does Removing commons-logging-1.1.jar fix it?
2) what if I really need to put commons-logging-1.1.jar in my application? How can I fix this?
Theres a fix pack of ibm for this.
https://www-304.ibm.com/support/docview.wss?uid=swg21502693
This happens because the class org.apache.commons.logging.impl.Jdk14Logger is loaded by a different classloader than the one that loaded the Log interface.
According to IBM's documentation, whenever you use a third-party library that WebSphere itself uses for its own internal purposes, you must:
Set your EAR's classloader policy to PARENT_LAST; and
Ensure that your EAR is self-sufficient. That is, that your third-party libraries (and their dependencies) are bundled within the EAR.
In your case:
Set your EAR's classloader policy to PARENT_LAST
Include commons-logging-1.1.jar within your EAR (you can place it in the "EAR Library" directory, usually EAR/lib).
Related
I am trying to do a log4j migration for a legacy application. I made the changes to the configuration files and tested it locally with Tomcat, where the logs were displayed correctly. However when I deploy on WAS, the logging stops.
I checked a lot of pages about the necessary dependencies and the possible problems, but now I feel I'm stuck. Here is what I already tried:
Added the log4j jars manually to the lib/ext directory in WAS (together with commons-logging, I read an article where it helped, although all these jar-s were already present in the ear)
Double checked, that the configuration file is on the classpath and that it's syntax is correct
Added logj42-web dependency
Added the necessary filters in web.xml (Spring version is 3.8, so also the config listener with the config name context-param)
Checked classloader in WAS - it's parent first
Am I missing something?
Any ideas are appreciated. Thank you in advance!
WAS includes its own commons-logging API (that does not utilize Log4j), so bringing your own logger requires a bit of extra class-loader-related config. Typically, that would go something like this:
Put your commons-logging and log4j jars, along with your logging properties files, in some directory (not WAS_HOME/lib/ext) readable by the user running the server.
Create a shared library on the server, with that directory as its class path, and select the "use an isolated class loader" option. Associate that shared library with your application or web module.
Ideally, that should be it. Isolated shared libraries search themselves before delegating to the server's loaders, so your application will "see" the commons-logging/log4j classes in the shared library instead of in the server, and likewise, it should pick up the configuration files from that directory instead of the ones found in the server.
You can also accomplish this same basic thing by leaving all the logging stuff in your WAR or EAR and setting its class loader to parent-last (which causes the class loader to search locally before delegating to the server-level loaders), but that is a bit riskier configuration - if your application includes APIs that are also provided by the server, parent-last class loading increases the possibility of ClassCastExceptions or LinkageErrors.
I have deployed the one ear inside the dropins folder and one of the war file from the ear is referencing the jar which i kept outside folder (Shared->config->lib->global). External jars which i kept global folder is again referring few jar which resides in the ear and this time i am getting "java.lang.NoClassDefFoundError"
Can you please suggest how to give reference .
server.xml
<webApplication contextRoot="/xyz" id="zyx" location="xyz.ear" name="xyz" type="ear">
<classloader commonLibraryRef="global,filterjars"></classloader>
</webApplication>
Common shared libraries cannot load classes from application binaries. When using common libraries, you can think of them as a one-way connection.
The application's classloader can delegate to common shared libraries, but not the other way around.
Common libraries are implemented as their own classloader so they must contain all dependencies.
On the other hand, private libraries have their classpaths appended to the application classloader's classpath - so they could load classes provided by the application, but this is not a good practice. For example, if a private library depends on ClassA that application1 provides, it will work just fine for application1, but might break in application2 that might not provide ClassA (or might provide an incompatible version of it).
If you have classes in your shared libraries that depend on classes in your application, I would either recommend putting all of those classes in the shared library - or putting all of the shared library classes in the application (or WAR, etc.). I personally prefer the latter - self-contained applications are much more portable and less likely to run into classloader/dependency issues (i.e. app1 needs version X of some dependency, but app2 needs need version X+5...).
Hope this helps,
Andy
Is there a way to make the Websphere Application Server use the jar places inside the application's WEB-INF/libs folder and ignore the one that available within the server's plugin folder.
I am using EMF in my application and the version provided in the server doesn't include support for EMF GenericType, so I want to make the application use the jar file inside the libs folder.
Thanks for any help
This is quite possible. You need to change the classloading order from parent first to parent last. This will cause it to consult the server runtimes version of the code after your application. This is documented in the infocenter.
Another approach you might want to consider is to use an isolated shared library. There is a good introduction for those in IBM Education Assistant. These are more complex to setup, but using parent last classloading order can sometimes cause unexpected side effects that don't occur with isolated shared libraries.
I am trying to get an apache camel app using CXF working on WebSphere.
Noticed a number of errors
Caused by: java.lang.IncompatibleClassChangeError: org.apache.neethi.AssertionBuilderFactory
at java.lang.ClassLoader.defineClassImpl(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:262)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:69)
This occurs because the org.apache.neethi classes are loaded from the WAS run-time instead of the neeti3.0.2.jar from WEB-INF/lib
here is the info from class loader:
class load: org.apache.neethi.builders.AssertionBuilder from: file:/D:/Tools/WebSphere/AppServer/plugins/org.apache.axis2.jar
The Web Application config has been changed to use the class loader policy. It is set to Parent Last. Yet this class seems to be using the Parent First Policy.
Is there anything in the CXF package that over-rides this policy?
I noticed that using Axis2 and WAS
http://axis.apache.org/axis2/java/core/docs/app_server.html
Avoiding conflicts with WebSphere's JAX-WS runtime has some additional steps mentioned for Axis2. Is there something similar that is required to get this to work?
Thanks
Manglu
Not specific to Camel, but we are dealing with a similar issue.
1) You can use an isolated shared library if you want. This seems to fix the classloader from pulling in these other libraries via OSGi. This solution isn't for everyone.
2) When setting an app that PARENT_LAST, make sure you're doing it in the correct place. If you have jars inside your wars, then you'll have to set PARENT_LAST on the WAR modules, not the application. In the WAS console> Applications > Application Type > websphere enterprise applications> MyEAR > manage Modules > MyWar > Change the "Class loader order" and make it "parent last"
3) After you make your changes, you can export the ear file. In the ear, there is a file META-INF/ibmconfig/cells/defaultCell/applications/defaultApp/deployments/defaultApp/deployment.xml that has this config. For maven ear's, you can put this into src/main/application for it to be packaged up with the ear.
Hope that this helps. Good luck.
We are discussing a similar topic at the Camel mailing lists. I suggest to take a look there: http://camel.465427.n5.nabble.com/camel-cxf-in-WebSphere-without-geronimo-jetty-depdendencies-possible-tp5726490.html
I am currently working on a portlet that is using the commons-collections jar file and am getting a NoSuchMethodError. To resolve this issue I need to change the classloader of my WAR file from PARENT_FIRST to PARENT_LAST (in the application.xml file).
However, when I do this my portlet will not launch and when I log into the console it displays the message "The portlet is temporarily disabled". If I change the classloader back to PARENT_FIRST then it will launch again but then I get the NoSuchMethodError.
Does anybody have any suggestions on how to fix this issue ?
I am not sure how, but today I started getting error messages in the logs when I was getting "The portlet is temporarily disabled". I was getting a java.lang.LinkageError which was down to the fact that I had the servlet-api-2.5.jar and a jaxb jar which was conflicting with webshpere j2ee.jar. Once I removed these dependencies and set the classloader to PARENT_LAST, it seems to work properly. It seems that a lot of people face similar issues. The link below is also useful http://forum.springsource.org/showthread.php?33663-dispatcher-servlet-quot-not-a-servlet-class-quot-in-websphere
#MTH,
please try adding commons-collections as a shared library. See here for an example on how others have used shared library support [1]. That will give you the steps, just do it for the jars that you need to override/replace from WAS's classloader
[1] http://portals.apache.org/jetspeed-2/deployguide/deploying-jetspeed-to-websphere.html#section_4_2
thanks,
dims
You haven't provided any logs... but still, one of the most important things to look out for when setting your application to run PARENT_LAST is that your application isn't bundled with any system-level classes that may conflict with the ones provided by WebSphere Portal. For example, classes that pertain to the Portlet specification or the JavaEE specification.