Develop Reference

Custom sonar rule - ClassNotFoundException: com.sonar.sslr.api.AstAndTokenVisitor

After deploy custom rule (like https://github.com/SonarSource/sonar-java/blob/master/java-checks/src/main/java/org/sonar/java/checks/UselessImportCheck.java), when I start SonarQube 4.2, following exception is thrown during sonar start:
Caused by: java.lang.ClassNotFoundException: com.sonar.sslr.api.AstAndTokenVisitor
at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50) ~[plexus-classworlds-2.2.3.jar:na]
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:244) ~[plexus-classworlds-2.2.3.jar:na]
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:230) ~[plexus-classworlds-2.2.3.jar:na]
... 44 common frames omitted
Above mentioned class should be found in sslr-core-1.19.2.jar, which I found in location sonarqube-4.2/web/deploy/plugins/squidjava/META-INF/lib/sslr-core-1.19.2.jar
Am I missing some step to enhnance default sonar libraries?
Currently installed plugins are(sonarqube-4.2/extensions/plugins):
sonarqube-4.2/extensions/plugins/sonar-checkstyle-plugin-2.1.jar
sonarqube-4.2/extensions/plugins/sonar-web-plugin-2.1.jar
sonarqube-4.2/extensions/plugins/sonar-jacoco-plugin-2.2.1.jar
sonarqube-4.2/extensions/plugins/sonar-java-plugin-2.2.1.jar
sonarqube-4.2/extensions/plugins/sonar-surefire-plugin-2.2.1.jar
sonarqube-4.2/extensions/plugins/sonar-pmd-plugin-2.2.jar
sonarqube-4.2/extensions/plugins/sonar-findbugs-plugin-2.2.1.jar
sonarqube-4.2/extensions/plugins/sonar-squid-java-plugin-2.2.1.jar
What should I do to prevent above mentioned exception(except undeploy mentioned custom plugin)?
Should be necessary libraries bundled directly in to the custom plugin? I expected sonar to have such libraries bundled.

Finally I found solution/explanation for the problem:
sonarqube-4.2/web/deploy/plugins/ directory is dynamically updated during sonar start from the sonarqube-4.2/extensions/plugins directory. Every plugin should have lib directory in his META-INF jar.Such lib directory should contain all necessary libraries.
In my case:
META-INF/lib/asm-5.0.1.jar
META-INF/lib/java-checks-2.2.1.jar
META-INF/lib/java-squid-2.2.1.jar
META-INF/lib/jaxen-1.1.4.jar
META-INF/lib/sslr-core-1.19.2.jar
META-INF/lib/sslr-squid-bridge-2.3.jar
META-INF/lib/sslr-xpath-1.19.2.jar
And META-INF/MANIFEST.MF must besides othet important definitions contain link to these libraries:
Plugin-Dependencies: META-INF/lib/java-checks-2.2.1.jar META-INF/lib/j
axen-1.1.4.jar META-INF/lib/sslr-squid-bridge-2.3.jar META-INF/lib/ss
lr-xpath-1.19.2.jar META-INF/lib/asm-5.0.1.jar META-INF/lib/sslr-core
-1.19.2.jar META-INF/lib/java-squid-2.2.1.jar
After these steps deploy success and plugin is ready to be used.
Above mentioned fact is may be clear for MAVEN users (there is lot of pom files),but gradle users must create such builds on their own and this information may be useful for them.
Good luck!

appengine 1.7.2 err after upgrade

I upgraded AE to 1.7.2 and now get the following error when first trying to access a page:
What can I do to get 1.7.2 working???
Could not initialize class com.google.appengine.tools.appstats.RecordingData
Caused by:
java.lang.NoClassDefFoundError: Could not initialize class
com.google.appengine.tools.appstats.RecordingData
at com.google.appengine.tools.appstats.Recorder.makeAsyncCall(Recorder.java:300)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.google.appengine.tools.development.agent.runtime.Runtime.invoke(Runtime.java:115)
at com.google.appengine.tools.appstats.AppstatsFilter.call(AppstatsFilter.java:231)
Note: the "RecordingData" class that could not be initialized is in the appengine-api-labs.jar is definately in my build path only now it is not working. I guess though that the Could not initialize class error means it's being found but not working. the NoClassDefFoundError is misleading I suspect.

I had the same issue recently, I started working on an existing AppEngine project which had been using the 1.7.1 API. I had a new eclipse setup using the newest plugin (1.7.2.1 at the time of writing).
In my case there was an older copy of the labs jar (appengine-api-labs.jar) in the build path. Deleting this and replacing it with the version from the AppEngine SDK in current use resolved the issue.
You'll find the labs jar in your eclipse plugins directory under: appengine-java-sdk-[X.X.X.X]\lib\impl).
Once you have replaced the jar do a clean build and you should be laughing.

First tomcat application - 'ant install' error "NoClassDefFound"

JSP/servlets are something I would like to learn, so I set about creating my first tomcat application.
I have gone through the apache tutorial here, and progressed to trying to install my application in tomcat (simple test html file with appropriate dir structure). Now, I realise its very wishful thinking hoping to use the stock build.xml provided by the tutorial but I need to start somewhere, Im not sure how to write one myself just yet. I have looked for examples, but they dont seem to have 'install' targets, perhaps they are not web applications.
My project builds, but does not install onto tomcat via ant. When I attempt to 'ant install' my console outputs...
ant install
Buildfile: /home/mark/svn/tomcatapp/build.xml
Trying to override old definition of datatype resources
prepare:
compile:
[javac] /home/mark/svn/tomcatapp/build.xml:299: warning: 'includeantruntime' was not set, defaulting to build.sysclasspath=last; set to false for repeatable builds
install:
BUILD FAILED
/home/mark/svn/tomcatapp/build.xml:375: java.lang.NoClassDefFoundError: org/apache/tomcat/util/buf/B2CConverter
at org.apache.catalina.util.Base64.encode(Base64.java:173)
at org.apache.catalina.ant.AbstractCatalinaTask.execute(AbstractCatalinaTask.java:204)
at org.apache.catalina.ant.DeployTask.execute(DeployTask.java:211)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:291)
at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.Target.execute(Target.java:392)
at org.apache.tools.ant.Target.performTasks(Target.java:413)
at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1399)
at org.apache.tools.ant.Project.executeTarget(Project.java:1368)
at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
at org.apache.tools.ant.Project.executeTargets(Project.java:1251)
at org.apache.tools.ant.Main.runBuild(Main.java:811)
at org.apache.tools.ant.Main.startAnt(Main.java:217)
at org.apache.tools.ant.launch.Launcher.run(Launcher.java:280)
at org.apache.tools.ant.launch.Launcher.main(Launcher.java:109)
Caused by: java.lang.ClassNotFoundException: org.apache.tomcat.util.buf.B2CConverter
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
... 19 more
Total time: 0 seconds
Why would a class fail to be found, would it not be contained within the tomcat install? There is a similar question, but I am not attempting to use the manager app, and I am not sure how to edit the class path - would I need to have compiled a .java class to create one for the project?
I am sure a more simple build file would suffice, but I am not sure which components are relevant. Sorry for the potentially very stupid questions.
Here is my install target from my build.xml file.
<target name="install" depends="compile"
description="Install application to servlet container">
<deploy url="${manager.url}"
username="${manager.username}"
password="${manager.password}"
path="${app.path}"
localWar="file://${build.home}"/>
</target>

If you're using the sample build.xml , change
localWar="file://${build.home}"
to
war="${dist.home}/${app.name}-${app.version}.war"
If you have catalina-ant.jar in ANT_HOME/lib. Try removing it from this location.
Restart tomcat.
That has worked for me.

Short answer:
copy file tomcat-util.jar from CATALINA_HOME/lib to ANT_HOME/lib OR
when issuing ant commands, add -lib option with a path to that file,
for example ant -lib C:\Tomcat8\lib\tomcat-util.jar install (provided CATALINA_HOME points to C:\Tomcat8)
Explanation:
I have encountered similar problem with Tomcat 8.0.36. According to error message class org.apache.tomcat.util.codec.binary.Base64 was not found. ant install command from the tutorial executes deploy task, that is not a standard task in Ant, but a custom task provided by Tomcat. Deploy task is implemented by DeployTask class (full name of the class is org.apache.catalina.ant.DeployTask) which is placed in CATALINA_HOME/lib/catalina-ant.jar. Custom tasks (like DeployTask) usually are dependent on external libraries, so you need to add those libraries to Ant's classpath. For more information see Optional Tasks in Ant.

You have hit https://issues.apache.org/bugzilla/show_bug.cgi?id=52148
Upgrade to the latest Tomcat 7 release and the problem will go away.

I am also running a new version of Tomcat (7.0.32) and encountered the same error while trying to follow the tutorial. I know this isn't the best solution, but perhaps it will be helpful in your debugging: When I use the -lib option with ant I was able to make it pull in the jar files with the needed classes:
ant -lib /usr/local/apache-tomcat-7.0.32/lib/ -lib /usr/local/apache-tomcat-7.0.32/bin/ install (In my case /usr/local/apache-tomcat-7.0.32 is $CATALINA_HOME)

GAE , Some Exception after upgrade datanucleus jar packages

When I changed the sdk orm jar to v2 (default including by sdk),I got some excepion info.It's about the datanucleus-core-3.0.6.jar has ben registed bla bla....
After search,I knew it was a bug in 3.0.6. So, I relpace it by datanucleus-core-3.0.10.jar.
But it not success when compile the pojo Enhancer
java.lang.RuntimeException: Unexpected exception
at com.google.appengine.tools.enhancer.Enhancer.execute(Enhancer.java:76)
at com.google.appengine.tools.enhancer.Enhance.<init>(Enhance.java:71)
at com.google.appengine.tools.enhancer.Enhance.main(Enhance.java:51)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.google.appengine.tools.enhancer.Enhancer.execute(Enhancer.java:74)
... 2 more
Caused by: java.lang.NoSuchMethodError: org.datanucleus.plugin.PluginManager.<init>(Lorg/datanucleus/PersistenceConfiguration;Lorg/datanucleus/ClassLoaderResolver;)V
at org.datanucleus.OMFContext.<init>(OMFContext.java:159)
at org.datanucleus.enhancer.DataNucleusEnhancer.<init>(DataNucleusEnhancer.java:172)
at org.datanucleus.enhancer.DataNucleusEnhancer.<init>(DataNucleusEnhancer.java:150)
at org.datanucleus.enhancer.DataNucleusEnhancer.main(DataNucleusEnhancer.java:1157)
... 7 more
this is my jar file in the \lib\user\orm
asm-3.3.1.jar
datanucleus-api-jdo-3.0.5.jar
datanucleus-api-jpa-3.0.6.jar
datanucleus-appengine-2.0.0-final.jar
datanucleus-core-3.0.10.jar
geronimo-jpa_2.0_spec-1.0.jar
jdo-api-3.0.jar
transaction-api-1.1.jar
I has been looking for all day. Does any know what problem with it?

You have old versions of datanucleus-core and datanucleus-enhancer in the CLASSPATH somewhere. "OMFContext" from that stack trace hasn't existed in DataNucleus for a very long time.

I think I know, why it does not work to upgrade the appengine with a new datanucleus. It is not a classpath entry! I discovered that in the ant-macro.xml, which triggers the enhancing-step, there is a link to the appengine-tools-api.jar and there is the class EnhancerTask. This is probably a link to the old version since the new datanucleus-enhancer-3.0.1.jar has it's own EnhancerTask class. So the only way to use the new versions of datanucleus with the old appengine sdk (in contrary to http://code.google.com/p/datanucleus-appengine/wiki/HowToUpdateTheSDKWithANewPluginVersion) is to do the enhancement-step by either ant (https://developers.google.com/web-toolkit/doc/1.6/tutorial/appengine) or probably the eclipse-datanucleus-plugin. Unfortunately this plugin does not work properly in my Eclipse. After install/configure the plugin there is still no project-context menu "datanucleus", where I am supposed to add the support. So I'll try the ant version.

maven - strange class not found exception

Hy,
I have a maven project.
mvn clean install
works perfect.
When deploying on my jboss server i receive this strange error:
Caused by: java.lang.ClassNotFoundException: No ClassLoaders found for: javax.ws.rs.core.Response
at org.jboss.mx.loading.LoadMgr3.beginLoadTask(LoadMgr3.java:212)
at org.jboss.mx.loading.RepositoryClassLoader.loadClassImpl(RepositoryClassLoader.java:521)
at org.jboss.mx.loading.RepositoryClassLoader.loadClass(RepositoryClassLoader.java:415)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
... 93 more
I've checked if artifact exists and it's there.
C:\Users\Cristian.m2\repository\org\jboss\resteasy\jaxrs-api\2.0-beta-4\
Does anyone have a work-around for this problem?

Your dependecy isn't in the deployed application. You may have to change the "provided" scope to "compile"
Resources :
Maven - Dependecy scope