I'm trying to connect to MySQL using JDBC connection in a Servlet.I'm using Eclipse and added the mysql-connector-java-5.1.20-bin.jar in /WEB_INF/lib folder.
Also the same jar is also added into Java Build Path.After running the project I'm getting the following error
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1678)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1523)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:186)
at com.shubh.Download.doGet(Download.java:42)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
Although I've added the required jar in the classpath. Why is the ClassNotFoundException still generating ?
Here is my code.
Usually, dropping .jar in WEB-INF/lib should work. eclipse is smart enough to recognize files added in WEB-INF/lib.
Just to check you can look in .classpath file to see whether it contains an entry like
<classpathentry kind="lib" path="WebContent/WEB-INF/lib/mysql-connector-java-5.1.20-bin.jar"/>
But, It is advised not to hassle with classpath entry. Remove all unnecessary reference from Java Build Path and then clean and build again should work.
Related
I am using eclipse e4 rcp application and am trying to use JfreeChart in it. So I have added the jcommon-1.0.16.jar,jfreechart-1.0.14.jar, jfreechart-1.0.14-experimental.jar and jfreechart-1.0.14-swt.jar in external jar file in Build path. I am getting the following error when I am running the application
org.eclipse.e4.core.di.InjectionException: java.lang.NoClassDefFoundError: org/jfree/data/xy/XYDataset
at org.eclipse.e4.core.internal.di.InjectorImpl.internalMake(InjectorImpl.java:344)
at org.eclipse.e4.core.internal.di.InjectorImpl.make(InjectorImpl.java:254)
at org.eclipse.e4.core.contexts.ContextInjectionFactory.make(ContextInjectionFactory.java:162)
.............
Caused by: java.lang.ClassNotFoundException: org.jfree.data.xy.XYDataset cannot be found by com.xyz.project_1.0.0.qualifier
at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:501)
Can anyone please suggest how to proceed?
There might be another jar that is missing. You need to check whether all jars are present in the Eclipse build path of your project.
Are you running the application from outside Eclipse IDE, on the command line?
If yes, then set classpath
SET CLASSPATH=pathtojar1;pathtojar2
before you execute your program.
Or specify classpath on the command itself
java -cp pathtojar1;pathtojar2;yourClassesFolderOrYourJar [ yourclassname or -jar yourjarname]
We are trying to create a functional example with Hibernate, JBoss7, Beans and Servlets using Eclipse as an IDE.
In other example project we were able to make functional Servlets, and we were able to use Hibernate.
We created two eclipse projects:
A Dynamic web project, an Enterprise Java Beans (EJB) project and a EAR project connecting both.
Running a simple test.java file which uses hibernate (and worked on other projects), we the get errors:
Initial SessionFactory creation failed.org.hibernate.cfg.beanvalidation.IntegrationException: Error activating Bean Validation integration
Exception in thread "main" java.lang.ExceptionInInitializerError
at exercicio.SessionFactoryUtil.<clinit>(SessionFactoryUtil.java:20)
at exercicio.DataBaseInterface.<init>(DataBaseInterface.java:17)
at exercicio.Test.main(Test.java:9)
Caused by: org.hibernate.cfg.beanvalidation.IntegrationException: Error activating Bean Validation integration
at org.hibernate.cfg.beanvalidation.BeanValidationIntegrator.integrate(BeanValidationIntegrator.java:156)
at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:303)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1750)
at exercicio.SessionFactoryUtil.configureSessionFactory(SessionFactoryUtil.java:32)
at exercicio.SessionFactoryUtil.<clinit>(SessionFactoryUtil.java:17)
... 2 more
Caused by: java.lang.NoClassDefFoundError: org/slf4j/LoggerFactory
at org.hibernate.validator.util.LoggerFactory.make(LoggerFactory.java:29)
at org.hibernate.validator.util.Version.<clinit>(Version.java:24)
at org.hibernate.validator.engine.ConfigurationImpl.<clinit>(ConfigurationImpl.java:59)
at org.hibernate.validator.HibernateValidator.createGenericConfiguration(HibernateValidator.java:41)
at javax.validation.Validation$GenericBootstrapImpl.configure(Validation.java:269)
at javax.validation.Validation.buildDefaultValidatorFactory(Validation.java:111)
at org.hibernate.cfg.beanvalidation.TypeSafeActivator.getValidatorFactory(TypeSafeActivator.java:445)
at org.hibernate.cfg.beanvalidation.TypeSafeActivator.activate(TypeSafeActivator.java:96)
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 org.hibernate.cfg.beanvalidation.BeanValidationIntegrator.integrate(BeanValidationIntegrator.java:150)
... 6 more
Caused by: java.lang.ClassNotFoundException: org.slf4j.LoggerFactory
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
... 19 more
The problem now seems to be around the jars that we included using project Properties > Java Build Path > Add External Jars for the EJB project:
We added the slf4j-jdk14-1.7.5.jar and hibernate jars but the exception log appears to be indicating that we are still missing some jar.
If we remove the jars from the Java Build Path, the exception log is the same. So we think that the jars are not being deployed correctly, or some extra configuration is required... even thought they appear in the /lib folder inside the EJB project deployment folder.
Is there any procedure we are missing, or any probable causes to investigate? I'll add more info if needed. Thanks.
When using JBoss7 not all Jars are available to the application by default (for example slf4j). You have to specify which modules should be included in the classpath of the application by putting this information into a file in your application.
I always do it by adding jboss-deployment-structure.xml into my application (the EAR in your case).
Here's how https://docs.jboss.org/author/display/AS7/Class+Loading+in+AS7.
(The name of the module in your case would be org.slf4j)
Throwing slf4j jar in the libs folder can create a conflict with the slf4j module already included in JB7 by default... you have to add the dependency to your jboss-deployment-structure.xml
But if your hibernate jars are in the libs folder, they could fail resolve the dependency as well too... the way to go in JB7 would be to make a module for Hibernate too, the Nightie builds of JB7 already include an hibernate module, you could just copy the module from there, then add it to your jboss-deployment-structure.xml
I have a maven project with spring. And we also have alot of JUnit test classes. We are using Eclipse. Every now and then - quite often actually - eclipse shows some (not all) of the test classes as red... Claiming it cant find imports. Looking at Eclipse error log, I can see alot of these error messages (but for different test-classes ofc).
What is happening? My collegue who works with the same project does not get this error. We are using Eclipse Juno SR2.
org.eclipse.core.runtime.CoreException: File not found: C:\xxx\target\test-classes\com\yyy\vet\zzz\service\TradeWashTest.class.
at org.eclipse.core.internal.filesystem.Policy.error(Policy.java:55)
at org.eclipse.core.internal.filesystem.local.LocalFile.openInputStream(LocalFile.java:377)
at org.eclipse.core.internal.localstore.FileSystemResourceManager.read(FileSystemResourceManager.java:797)
at org.eclipse.core.internal.resources.File.getContents(File.java:289)
at org.eclipse.jdt.internal.core.util.Util.getResourceContentsAsByteArray(Util.java:1132)
at org.eclipse.jdt.internal.core.builder.IncrementalImageBuilder.writeClassFileCheck(IncrementalImageBuilder.java:888)
at org.eclipse.jdt.internal.core.builder.IncrementalImageBuilder.writeClassFileContents(IncrementalImageBuilder.java:830)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.writeClassFile(AbstractImageBuilder.java:857)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.acceptResult(AbstractImageBuilder.java:188)
at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:510)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:365)
at org.eclipse.jdt.internal.core.builder.IncrementalImageBuilder.compile(IncrementalImageBuilder.java:329)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:302)
at org.eclipse.jdt.internal.core.builder.IncrementalImageBuilder.build(IncrementalImageBuilder.java:134)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.buildDeltas(JavaBuilder.java:265)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.build(JavaBuilder.java:193)
at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:726)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:199)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:239)
at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:292)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:295)
at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:351)
at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:374)
at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:143)
at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:241)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:53)
Caused by: java.io.FileNotFoundException: C:\dev\xxx\target\test-classes\com\yyy\vet\zzz\service\TradeWashTest.class (The system cannot find the path specified)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(Unknown Source)
at org.eclipse.core.internal.filesystem.local.LocalFile.openInputStream(LocalFile.java:368)
... 26 more
The problem could be in the jars dependencies (especially if you're using mocks). You need to perform two steps to figure out what the problem is:
1.Run unit tests using maven (in case it works you can go to step2);
2. Look into jars order in the Eclipse (projects setting-> java build path-> order and settings).
In case you said that it works for your colleague you need to compare order of your jars with jar's order of you colleague
The error I'm getting is well discussed here, but I still can't seem to get a grip on what I'm doing wrong.
I'm trying to run a simple code with java3d. I added the jard to the Maven Dependencies and they are showing up. No errors are displayed and everything seems fine.
But when I'm trying to compile the code, all of a sudden the message
Exception in thread "main" java.lang.UnsatisfiedLinkError: no J3D in java.library.path
at java.lang.ClassLoader.loadLibrary(Unknown Source)
at java.lang.Runtime.loadLibrary0(Unknown Source)
at java.lang.System.loadLibrary(Unknown Source)
at javax.media.j3d.MasterControl$22.run(MasterControl.java:889)
at java.security.AccessController.doPrivileged(Native Method)
at javax.media.j3d.MasterControl.loadLibraries(MasterControl.java:886)
at javax.media.j3d.VirtualUniverse.<clinit>(VirtualUniverse.java:229)
at de.act.gui.Skelett3D.main(Skelett3D.java:15)
appears.
Apparently I'm just missing some trivial error. Since the question has been asked so many times, the answer should be somewhere.
I added the Jars via the pom.xml with
<dependency>
<groupId>java3d</groupId>
<artifactId>j3d-core-utils</artifactId>
<version>1.3.1</version>
</dependency>
You are missing a native library (i.e. a dll or so file).
I do not know how to correctly reference that from maven (apparently there is something like a NAR that you can built, but I have not researched that yet).
A quick solution for eclipse is to add the dll as a native dependency to your Maven Dependencies library in eclipse:
In the "Libraries" tab in "Java Build Path" in the project properties, expand "Maven Dependencies" and edit "Native library location" to point to the directory containing your native library.
If the above solution is not working try to manually install maven and j3d, or reinstall it.
a missing file is sometimes a really bad sign, because sometimes if 1 file is missing maybe you haven't installed propertly and other files will be missing later on so i suggest you reinstalling.
I am developing a stand-alone java application which uses eclipselink. It is all fine when I execute the app from eclipse IDE. But I've exported an executable JAR file, and since than I can not make eclipseLink work.
I have found similar issue in the Eclipse community forum here, but yet not too handy:
Please help,
My exception is the following:
01 dec. 2010 22:47:31,199 INFO Configuration:97 - Iniciate database
Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoa
der.java:56)
Caused by: Exception [EclipseLink-30005] (Eclipse Persistence Services - 2.0.2.v
20100323-r6872): org.eclipse.persistence.exceptions.PersistenceUnitLoadingExcept
ion
Exception Description: An exception was thrown while searching for persistence a
rchives with ClassLoader: java.net.URLClassLoader#61de33
Internal Exception: Exception [EclipseLink-30004] (Eclipse Persistence Services
- 2.0.2.v20100323-r6872): org.eclipse.persistence.exceptions.PersistenceUnitLoad
ingExceptionException Description: An exception was thrown while processing persistence.xml
from URL: rsrc:../
Internal Exception: java.net.MalformedURLException
at org.eclipse.persistence.exceptions.PersistenceUnitLoadingException.ex
ceptionSearchingForPersistenceResources(PersistenceUnitLoadingException.java:126
)
at org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFa
ctory(PersistenceProvider.java:133)
at org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFa
ctory(PersistenceProvider.java:65)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.
java:51)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.
java:33)
at eu.agilelabs.pillAgent.db.dam.DataManagerImplJPA.(DataManagerIm
plJPA.java:36)
at eu.agilelabs.pillAgent.db.dam.DataManagerImplJPA.getInstance(DataMana
gerImplJPA.java:47)
at eu.agilelabs.configuration.Configuration.(Configuration.java:98
)
at eu.agilelabs.configuration.Configuration.getInstance(Configuration.ja
va:119)
at eu.agilelabs.pillAgent.core.Main.main(Main.java:15)
... 5 more
Caused by: Exception [EclipseLink-30004] (Eclipse Persistence Services - 2.0.2.v
20100323-r6872): org.eclipse.persistence.exceptions.PersistenceUnitLoadingExcept
ion
Exception Description: An exception was thrown while processing persistence.xml
from URL: rsrc:../
Internal Exception: java.net.MalformedURLException
at org.eclipse.persistence.exceptions.PersistenceUnitLoadingException.ex
ceptionProcessingPersistenceXML(PersistenceUnitLoadingException.java:117)
at org.eclipse.persistence.internal.jpa.deployment.PersistenceUnitProces
sor.processPersistenceXML(PersistenceUnitProcessor.java:444)
at org.eclipse.persistence.internal.jpa.deployment.PersistenceUnitProces
sor.processPersistenceArchive(PersistenceUnitProcessor.java:401)
at org.eclipse.persistence.internal.jpa.deployment.PersistenceUnitProces
sor.getPersistenceUnits(PersistenceUnitProcessor.java:310)
at org.eclipse.persistence.internal.jpa.deployment.JPAInitializer.findPe
rsistenceUnitInfoInArchive(JPAInitializer.java:149)
at org.eclipse.persistence.internal.jpa.deployment.JPAInitializer.findPe
rsistenceUnitInfoInArchives(JPAInitializer.java:136)
at org.eclipse.persistence.internal.jpa.deployment.JPAInitializer.findPe
rsistenceUnitInfo(JPAInitializer.java:125)
at org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFa
ctory(PersistenceProvider.java:98)
... 13 more
Caused by: java.net.MalformedURLException
at java.net.URL.(Unknown Source)
at java.net.URL.(Unknown Source)
at java.net.URL.(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.setupCurrent
Entity(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLVersionDetector.determineD
ocVersion(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(U
nknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(U
nknown Source)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown So
urce)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Un
known Source)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.p
arse(Unknown Source)
at org.eclipse.persistence.internal.jpa.deployment.PersistenceUnitProces
sor.processPersistenceXML(PersistenceUnitProcessor.java:442)
... 19 more
I think this line must be the key:
Internal Exception: Exception [EclipseLink-30004] (Eclipse Persistence Services
- 2.0.2.v20100323-r6872): org.eclipse.persistence.exceptions.PersistenceUnitLoad
ingExceptionException Description: An exception was thrown while processing persistence.xml
from URL: rsrc:../
I have managed to solve it. I changed the way eclipse exports the jar file. If it extracts required libraries into the jar everything works great. Thank you anyway!
Some background info
As the link you've provided says, EclipseLink doesn't seem to support loading persistence.xml when the EclipseLink jar is embedded in your app's jar.
As I understand it, standard non-customized Java doesn't support runnable jars that load classes from embedded jars. The runnable jar that Eclipse creates is able to overcome that limitation by adding a custom classloader (org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader) to your app's jar. The custom classloader apparently is where EclipseLink runs into this issue.
With that said, in Eclipse Helios, I've found it more manageable to "Copy required libraries into a sub-folder next to the generated JAR" rather than to "Extract required libraries into generated JAR."
Choosing the copy option keeps the eclipselink jar intact, as opposed to Eclipse extracting the various .class files and cluttering your application's jar. True, your app will no longer be distributable as a single jar, but from a manageability standpoint, this seems better than the extract-libraries option.
I found the respective solution (that is if you are not using EclipseLink 2.3.2), as mentioned by GaDo in Bug 364748, the solution is to add the following line into MANIFEST.MF
Eclipse-BundleShape: dir
This leads to the plug-in being exported as directory instead as JAR file, which makes persistence.xml accessible.
I was using EclipseLink 2.3.2, with Eclipse Indigo, and was still getting the error.
Then, like a fool, I realized that I was choosing "Package required libraries into generated JAR" instead of "Extract required libraries into generated JAR" works.
Not sure what the difference is, although I've noticed that some of my JARs only work when I create when using "Package required...", and others only work when I create them using "Extract required...".
Not sure why that is. Ultimately, I don't really care, as long as the resulting JAR has no external dependencies.
BTW, the other option that was proposed (modifying the JAR's manifest file) didn't work for me. I extracted the manifext (jar xf MYJAR.jar META-INF/MANIFEST.MF), added Eclipse-BundleShape: dir, injected it into the jar (jar umf META-INF/MANIFEST.MF MYJAR.jar), and verified that the manifest changed. Same error.
Right click on the project -> Properties -> Java Build Path -> Order and Export, and select the libraries
Right click on the project -> Export... -> Runnable JAR file -> Copy required libraries into a sub-folder next to the generated JAR
This worked for me.
This issue has been fixed in EclipseLink 2.3.2
I upgraded and it went away