Java EE, GWT, NoClassDefException - gwt

I have an app, built on GWT (google web toolkit) and JPA (eclipselink 2.3). it's not using GAE (app engine).
when I finished application, I ran 'google->gwt compile' menu in eclipse and then uploaded /war content to the tomcat directory...
application is running, but when I try to do one specific action in gui, I get an error message and Tomcat log contains this exception: http://paste2.org/p/1879857 (java.lang.NoClassDefFoundError)
during development of the application, I encountered this kind of exception several times, it was always caused by absence of library .jar file in the war/WEB-INF/lib/... anytime it has occurred, I stored .jar to the folder and it worked... but not this time...
this class is located in gwt-dev.jar (yes, it is there - have searched the archive) and it didn't help me to store archive to the lib/ folder...
it is also included in classpath, and compiler had no problem... compilation finished without errors (so compiler can see the class).
do you have any idea, how to make tomcat to see the class?
thanks

gwt-dev.jar shouldn't be in WEB-INF/lib/, it is the GWT compiler, and shouldn't be needed or used at runtime. At the same time, that HashSet (com.google.gwt.dev.util.collect.HashSet, part of dev mode) shouldn't be used outside the compiler - use java.util.HashSet instead.

Change the HashSet import in GroupImpl.java from com.google.gwt.dev.util.collect.HashSet to java.util.HashSet. You shouldn't need gwt-dev.jar to run your application.

Related

Could not find file ${libs.jsf20.classpath} to copy

I'm trying to build a web app in Netbeans. In project properties, I have four libraries - JSF2.2, MySQL JDBC Driver, PrimeFaces 5.0 and Java EE Web 7 API Library (all of them embedded in NetBeans, nothing was additionally downloaded). When I was creating the project, I selected JSF2.2 framework and Primefaces.
When I try to build (or clean and build) my project, I get the following error:
Warning: Could not find file E:\My Documents\NetBeansProjects\ConferenceManager\${libs.jsf20.classpath} to copy.
Any ideas?
Solved!
I removed the "default" library and included separate .jar fil that I had downloaded. That solved the problem with JSF, but then the same problem happened with MySQL connector (and I solved it the same way).

ClassNotFoundException oracle.jdbc.driver.OracleDriver only in servlet, using Eclipse and oracle

The code below fails on the line: Class.forName("oracle.jdbc.driver.OracleDriver");
with the error:
java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver
The two printlns print: Wed_Jun_22_11:18:51_PDT_2005 false This makes me think the class exists and can be found. Also this exact same class works in an a non-servlet application.
I have rebooted everything multiple times and regenerated the application/servlet multiple times. All values have been hard coded to make it simple and short.
I'm using: Eclipse JavaEE 1.4.2 Tomcat 7 jdk1.7 Oracle 11g R2 Windows 7 64bit
I have already added the jar files in web-inf. but it is still giving the following error: java.lang.NoClassDefFoundError: oracle/jdbc/driver/OracleDriver.
Any suggestions would be great.
It is a bit hard to tell what exactly going wrong without looking into your application and tomcat server. But there are a couple of hints for your issue.
NoClassDefFoundError always makes me think that there is class collision rather than missing jar file. Be ware of the difference between ClassNotFound and NoClassDefFoundError
tomcat loads class in a different way as what normal java app does. Normally, the class loaders in a stand along java app will follow delegate pattern, which means the child class loader will always delegate the class loading job to its parent class loader. But tomcat does not exactly follow this. So it will load(find source file, read byte code and create a instace of class Class) by itself.
So check your tomcat lib as well as all the web apps under the tomcat and see if there are multiple version of ojdbcXXX.jar
Go through C:\apache-tomcat-7.0.47\lib path(this path may be differ ->based on where you pasted the Tomcat server ) then past ojdbc14.jar if its not contain.
Then restart the server in eclipse then run your app on server

How to View Classpath While Debugging in Eclipse

I'm trying to troubleshoot a GWT-based app I'm writing in Eclipse. It currently uses Spring Framework 3.1.1 and Hibernate 4.1.6 on the back-end side. I'm currently having troubles with the dreaded "javax.validation.ValidationException: Unable to find a default provider" that seems to plague a lot of folks but is caused by different problems. I've tried the various solutions of using different versions of the JSR 303 implementation (e.g. diff. versions of Hibernate Validator) but it doesn't seem to make a difference.
And after debugging, I'm seeing why. Once execution gets to javax.validation.Validation.getValidationProviders():317 (in validation-api-1.0.0.GA), the app (running on an Eclipse internal Jetty server) attempts to read the META-INF/services/javax.validation.spi.ValidationProvider resource from the classpath and comes back empty. I am absolutely certain that the different validator implementations I've put (e.g. hibernate-validator-4.3.0.Final.jar) have that resource and it does contain a value (e.g. org.hibernate.validator.HibernateValidator), but is not appearing to the classloader in question. The way I've included the JAR in the classpath is by adding it to the project's Build Path which seems to add it to the Jetty runtime when I execute the applications.
My question is: Is there a way to view the classpath in Eclipse debug mode visible to a certain classloader? Secondly, does anyone know why the Hibernate Validator's resource is not first and foremost in the classloader that Validation is using?
The webapp classpath is composed by the directory WEB-INF/classes and by all the jars in WEB-INF/lib. If you want a jar to be available at runtime, you must NOT add it to the build path, but to WEB-INF/lib.
Dropping a jar in WebContent/WEB-INF/lib in Eclipse will make it automatically part of the buid path of your webapp, and available at runtime.

JBoss 5.x and Axis2

What libraries are required to run a Web Service Client that has been generated from Axis 2 on JBoss. So far I have not found anything in my searches.
I assume that the following error:
org.jboss.xb.binding.JBossXBRuntimeException: Failed to create a new SAX parser
Is due to the fact that I have place every jar file from Axis lib folder into my projects
My Solution
Did it the hard way - added and subtracted jars from my lib directory until I got it to deploy and run with no exceptions
Is what you have pasted the root cause of the stack trace? In case it is not, the problem is that probably your app is deployed with xerces related jar files in it (ex: xercesImpl-x.x.x.jar). JBoss is shipped with the xerces jars in its JBOSS_HOME/lib/endorsed folder. If the same classes are deployed with your web app this may result in class loading issues.
You can try to remove the xerces libs from your app and then test the web service client again.
Cheers!

How to use 3rd party libraries in glassfish?

I need to connect to a MongoDB instance from my EJB3 application, running on glassfish 3.0.1. The Mongo project provides a set of drivers, and I'm able to use them in a standalone Java application.
How would I use them in a Java EE application? Or maybe better phrasing: how would I make a 3rd party library available to my application when it runs in an EJB container?
At the moment, I'm getting a java.lang.NoClassDefFoundError when deploying a bean that
tries to import from the library:
[#|2010-03-24T11:42:15.164+0100|SEVERE|glassfishv3.0|global|_ThreadID=28;_ThreadName=Thread-1;|Class [ com/mongodb/DBObject ] not found. Error while loading [ class mvs.core.LocationCacheService ]|#]
[#|2010-03-24T11:42:15.164+0100|WARNING|glassfishv3.0|javax.enterprise.system.tools.deployment.org.glassfish.deployment.common|_ThreadID=28;_ThreadName=Thread-1;|Error in annotation processing: java.lang.NoClassDefFoundError: com/mongodb/DBObject|#]
[#|2010-03-24T11:42:15.259+0100|SEVERE|glassfishv3.0|javax.enterprise.system.core.com.sun.enterprise.v3.server|_ThreadID=28;_ThreadName=Thread-1;|Exception while loading the app
org.glassfish.deployment.common.DeploymentException: java.lang.NoClassDefFoundError: com/mongodb/DBObject
at org.glassfish.weld.WeldDeployer.event(WeldDeployer.java:171)
at org.glassfish.kernel.event.EventsImpl.send(EventsImpl.java:125)
at org.glassfish.internal.data.ApplicationInfo.load(ApplicationInfo.java:224)
at com.sun.enterprise.v3.server.ApplicationLifecycle.deploy(ApplicationLifecycle.java:338)
I tried adding it to the NetBeans project (Properties -> Libraries -> Compile -> Add Jar, enable 'Package'), and I also tried manually copying the jar file to $GF_HOME/glassfish/domains/domain1/lib (where the mysql-connector already resides).
Do I need to 'register' the library with the container? Reference it via Annotation? Extend the classpath of the container to include the library?
Hmm... Shouldn't you put this "driver" in glassfishv3/glassfish/domains/domain1/lib/ext?
You could put shared libs to lib/ext of your domain. commons-logging and jdbc drivers are often added in this domain path.
Common Class Loader
GlassFish v2 has a well defined Class
Loader hierarchy which identifies the
common class loader as the proper way
to deal with shared libraries. So to
make a long story short, putting you
libraries and other framework JARs in
domains/domain1/lib is all you need to
do.
lib/, not lib/ext
The person asking me the question had
tried putting the libraries in
domains/domain1/lib/ext which
triggered an interesting
ClassNotFoundError for core Java EE
classes such as
javax.servlet.http.HttpServlet. Shing
Wai Chan was quick to explain that
domains/domain1/lib/ext is part of
-Djava.ext.dirs which makes any of its JARs be considered as a JDK extension
which means web app frameworks placed
there will be loaded before
webcontainer implementation classes as
they are higher up in the classloader
delegation chain.
Glassfish has own Class loader hierarchy, http://docs.oracle.com/cd/E19798-01/821-1752/beade/index.html
I face the same problem in my project and then I put all my Third party libraries in domain/domain1/lib and my problem solved. On other way round, my problem was solved too by putting libraries in glassfish/lib.
In my case I was using Oracle Express Edition 11gR2 and Glassfish 3.1.2 and the ONLY way that works in my case was putting the ojdbc6 in:
C:\Program Files\glassfish-3.1.2.2\glassfish\lib
Go to your Glassfish doamin directory.
Then go to lib folder.
Place the libraries there.
Restart the glassfish and run.
(Ex) C:\glassfish3\glassfish\domains\domain1\lib
Try to put Your libs into $GF_HOME/glassfish/modules/.
It's dirty, but will work.