I have an issue in loading jars in websphere server. Some of the jars are present in WEB-INF/lib and some are present in local hard drive(ex., c:\lib folder). How can i load all these jars, during the startup of the application. If WEB-INF jars are loaded, external jars are not getting loading and viceversa..Need help on this....
WebSphere has a hierarchy of classloaders, parent classloaders cannot see child classloaders, hence you get surprises when you put different aspects of your application in different places.
Never attempt to place application jars in WebSphere's own lib directory, and never adjust WebSphere's own class path. There is ana rchitected way to make external jars visible, I'll explain that in a moment.
There are three places that you can put JAR files so that they will be loaded. By far the the best is simply to place the JARs in WEB-INF/lib. You can specify the search order preference PARENT LAST so that these take prececdence over jars supplied by websphere - but note that some fundamental jars cannot be over-ridden You cannot replace the IBM security for example.
Second you can add jars to the root of the EAR file. Noe that the hierarchy comes into play now, WEB-INF/lib jars can see EAR jars but EAR jars cannot see WEB-INF/lib jars.
Finally you can specify a WebSphere "Shared Libarary". See the Info Centre for how, it's very easy through the console. A shared library has a classpath, you add jars to that. Then you allocate the shared libarary to individual applicaitons or whole servers.
Once again You WEB app can see the shared library, but i don't beleive taht the convers is true. Hence putting framework code in a shread library may not work for you.
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This is a strange problem. I have an existing JEE project that is and has been in production on WebSphere 7. It is a multi-module EAR file. It has 2 WARs and 1 shared Java project. Most of it is Spring 4 based, but we have some web services we host using axis2 (1.5.4). This project does not use Maven. It does use a WebSphere deployment.xml (in the EAR) with the warClassloaderPolicy="SINGLE" and the classloader mode="PARENT_LAST". This controls the classloader policies for this EAR. All the jar files that the Java project and the WARs rely on are stored at the EAR level and referenced at the module level via the manifest files. That all works fine and has for several years.
Now I was trying to convert this project to a Maven project after all these years. Initially, I left the deployment.xml file settings as they always have been. But with these settings I was getting:
java.lang.VerifyError at com.sun.xml.bind.v2.model.impl.RuntimeBuiltinLeafInfoImpl "org.springframework.oxm.jaxb.Jaxb2Marshaller".
After much googling on this site and all around and trying 50,000 things, I tried one thing, which worked for most of the app. I switched the classloader mode to "PARENT_FIRST" and all of a sudden the WAR that exclusively uses Spring 4 worked. It started up without error and I was able to run it.
But, the other WAR which hosts the axis2 web services started getting the error:
org.apache.axis2.deployment.WarBasedAxisConfigurator <init> org.apache.commons.fileupload.FileUploadException....Caused by: java.lang.NoClassDefFoundError: org.apache.commons.fileupload.FileUploadException....Caused by: java.lang.ClassNotFoundException: org.apache.commons.fileupload.FileUploadException
This class (org.apache.commons.fileupload.FileUploadException) is in both the compile and runtime classpath. In eclipse I can see it in the "Maven Dependencies" library that the m2e eclipse plugin creates from the POM files. I can also see this jar in the WebSphere runtime module classpath inspector (it shows up in there 3 times! Once under each WAR and once just in a list from the Maven repository location.)
One thing of note is that I've configured the project with a parent POM, where most of the dependencies are declared at the parent and then are inherited for each of the modules. In the EAR project, the POM is using the maven-ear-plugin with skinnyWars=true. However, it appears the skinnyWars directive is not respected when the m2e eclipse plugin deploys the EAR into the local WebSphere server (that is evident because I see these jars showing up in the classpath 3 times). But when I create an EAR using the Maven build, the EAR comes out correctly with each jar only showing up in the EAR one time.
This is my last hope to post something here and see if someone has an idea for something to try, otherwise I can't think of anything else to try.
Thanks...
Is there a particular reason you need to run with a single class loader for all the WAR modules, other than convenience? If not, you could rework the application in order to allow you to run PARENT_FIRST in the Spring WAR and PARENT_LAST in the Axis2 WAR.
If that's not an option for some reason, the path of least resistance might be to go back to PARENT_LAST and remove some libraries from the app or module. The VerifyError generally occurs if you're running with PARENT_LAST and have a library in the app that is also present in the server - in this case, the exception looks like it's coming out of JAXB, so you might want to see if simply removing JAXB (and perhaps JAXP, if present, since it's heavily used by JAXB) from the application resolves the issue with your default setup.
You could also stick with PARENT_FIRST and move the Axis2 jars to an shared library with an isolated class loader, associated with the app. An isolated shared library would make just the stuff in the shared library PARENT_LAST, so you can avoid the VerifyError and still get PARENT_LAST for Axis2. The issue in the PARENT_FIRST case appears to be because you're picking up WebSphere's copy of Axis2 but somehow have a dependency inserted from your app's copy - the failing class load is occurring in a server-level loader, so it doesn't see the copy in your app.
The size of my EAR file has reached around 100 MB after adding many exetrnal jars.
Environment : Java Spring/Websphere application server/Maven
Please share the tips to reduce the size of an EAR file.
Seems the exteral jars contribute most to the large size. Is it possible to follow an approach like below, if so how to do that?
Do the maven build with compile scope for large jars
Keep the large sized jars in app server lib, with this will the app take these jars at runtime from appserver?
Thanks
Smitha
You should really review your jars, especially poorly done Maven builds add a lot of unnecessary jars to the application (like jta, servlet, jee-api, etc..), so make sure you don't have them. Sometimes jars are duplicated in every web module you have in the EAR.
Second WebSphere is Java EE 6 server, so it provides lots of common features like JAX-WS, JAX-RS, JPA, etc..., so you should consider using them, before throwing all that as third party libraries in your application.
If you want to use shared library approach, do not put the jars in the server lib folder or server classpath. This is not recommended.
Create Shared library via Environment > Shared libraries see here and assign them to the application.
To reduce the War size you can consider
Static Content :Keep the Static content like images etc out of the war file and refer them via application using references to location.
Shared Libs : if majority of the size is contributed by Shared Libs you can separate that out of war. to do that you can place the war libraries in one of the following locations
a) In Server Lib folder, Not Recommended since different apps might use diff versions.
b) In Server App Lib Folder
b) In a shared folder and including that folder into class path .
c) Use exploded war deployment deploying only changes.
After exploring the OSGi framework, I had developed a sample web application.The Web Application Bundle(.war or .jar) is packaged inside an eba.
The war file contains a bunch of embedded jar files in its WEB-INF/lib
directory.These jars have been converted to OSGi bundles(using maven-bundle-plugin) with the required export and import packages as per the relation between the jars.
Now I have to even mention all these jars(WEB-INF/lib) in the bundle-classpath.
The above works because a bundle(wab is also a bundle) can include one or more jarfiles within it, and use a Bundle-Classpath manifest.mf entry to point to them.
Incase I dont include the jars in the bundle-classpath I get a ClassNotFoundException.
The question is,then there's no point converting the jars to osgi bundles.Obviously all the jars in the WEB-INF/lib are loaded by the same class loader(i.e wab's class loader) ,so then we are not reaping the major benefits of OSGi which is mainly a per bundle classloader concept?
Putting jars inside the WEB-INF/lib is the old-style normal-java way of handling dependencies, and putting them outside the war is the new-style OSGi way of handling them.
By packaging your war's dependencies in WEB-INF/lib, you're treating them as normal jars (remember a bundle is also a jar). So in that case, you're right that there wasn't much point in using bundles.
One of the benefits of using wabs instead of wars is to get away from the dreaded 100 Mb monolithic war. Rather than packaging the bundles inside WEB-INF/lib, try having the war import the packages it needs using Import-Package:, and package the dependencies inside the eba. (If you don't remember to have the war import the packages it needs, you'll get the class not found exceptions you were seeing, because the OSGi container won't know your war needs those packages.)
I want to develop a RESTful API within my multi-module Spring-based project using Spring Rest. For that purpose, I have a webapp module and some other business/data layer modules. For example, this would be my simplified project structure:
myProject
-- webapp (war-packaged)
-- business (jar-packaged)
-- data (jar-packaged)
Business module depends on data module and so does webapp on business module. Webapp imports successfully every module's application context. Now I want to be able to use some business module classes that do some kind of calculation according to some data retrieved from a DB in order to provide a certain resource. All examples I had a look at were quite simple and this multi-module approach was not covered at all.
What is the problem? As far as I am concerned, Tomcat loads classes in a certain order. Concretely, it first loads WEB-INF/classes and only then WEB-INF/lib (where all webapp dependencies are placed, business module in this case). So, there goes my question. Where should I place my Controller classes? If I place them within the webapp module I won't be able to autowire any business-module bean since Tomcat will throw a ClassNotFoundException when I deploy the webapp war (at least this is the behaviour I have experienced).
The answer is probably easy but I'm quite new to Spring and its world!
Thank you all in advance.
Your business and data jars would go into the WEB-INF/lib directory. Then those jars will automatically be added to the CLASSPATH for your app when you deploy it. You will need to deploy your application as a WAR file.
Ideally, you would build the business and data jars, add them to some repository, and then the build system would pull the proper version of each jar into the WEB-INF/lib directory for you.
And as to the original question, the controller classes go into the webapp/src directory.
Assuming you are using Maven 2. Make sure your assembly creator (e.g. maven war module) is including your dependent .jar files within the final .war file's WEB-INF/lib directory. This should be the default procedure (per: http://maven.apache.org/plugins/maven-war-plugin/war-mojo.html#dependentWarIncludes ). The other concern, then is whether your sub-projects (business and data) are even creating jars so that they could be included in the WAR output.
If you have doubts as to the contents of that war file, browse the listing of it by executing
'jar tvf $WAR_FILENAME' from the command line and by observing the WEB-INF/lib directory contents. You should see your business and data jars in there. Go further by exploding your war file, then browsing the contents of business and data jar (using 'jar xvf $FILENAME' to explode in a new directory).
Hope this helps!
I have a project with more than an hundred external library dependencies, here we use tomcat with this endorsed jar libs configured on a directory in the server (now is under $CATALINA_HOME/lib/endorsed), so the webapp can access those resources on runtime start.
I wanted to try jetty instead, because tomcat takes too much memory and crashes frequently. Now I'm wondering if there is a parameter to pass on maven-jetty-plugin to specify this jar's folder so as the webapp class loader find them in its classpath.
I've tried extraClasspath in configuration tag, but it seems to load only classes and ignore all jars in the directory I set into (if I pass the full name path of the jar, it is loaded, but I don't want to set every library that I need there).
Thanks in advance for the help
update:I know it's not a standard maven operation, i'm searching for an emergency workaround since this project is very huge and I can't refactor as I want.
But also I expected this feature was not as tricky as it seemed to me at first glance.
You need to pass them as absolute paths, or, alternatively, have them as dependencies of the plugin itself.
What you want to have done goes against Maven's portability principles, so don't expect it to support it.