OSGI bundle: NoClassDefFoundError

Question

I got this exception starting my bundle:

java.lang.NoClassDefFoundError: gnu/io/SerialPortEventListener

My bundle is using this bundle:[1]enocean library the enocean library[1] is using the rxtx library that I added it as a bundle in my project, the rxtx contains the not found class: "SerialPortEventListener"

the EnOcean library[1] is declaring the package gnu.io as an imported package , and the bundle rxtx is exporting the package, the package version is the same.

I found out that the error NoClassDefFoundError is lanched if the class depends of another class that can't be found, but the SerialPortEventListener is an interface inhiriting from EventListener.

Can't find out why the equinox can't found it.

!ENTRY org.eclipse.equinox.ds 4 0 2015-06-22 12:55:02.616
!MESSAGE [SCR] Exception while activating instance org.eclipse.kura.binding.enocean.EnOcean@79d49d of component org.eclipse.kura.binding.enocean
!STACK 0
java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.eclipse.equinox.internal.ds.model.ServiceComponent.activate(ServiceComponent.java:235)
        at org.eclipse.equinox.internal.ds.model.ServiceComponentProp.activate(ServiceComponentProp.java:146)
        at org.eclipse.equinox.internal.ds.model.ServiceComponentProp.build(ServiceComponentProp.java:347)
        at org.eclipse.equinox.internal.ds.InstanceProcess.buildComponent(InstanceProcess.java:620)
        at org.eclipse.equinox.internal.ds.InstanceProcess.buildComponents(InstanceProcess.java:197)
        at org.eclipse.equinox.internal.ds.Resolver.buildNewlySatisfied(Resolver.java:473)
        at org.eclipse.equinox.internal.ds.Resolver.enableComponents(Resolver.java:217)
        at org.eclipse.equinox.internal.ds.SCRManager.performWork(SCRManager.java:816)
        at org.eclipse.equinox.internal.ds.SCRManager$QueuedJob.dispatch(SCRManager.java:783)
        at org.eclipse.equinox.internal.ds.WorkThread.run(WorkThread.java:89)
        at org.eclipse.equinox.internal.util.impl.tpt.threadpool.Executor.run(Executor.java:70)
Caused by: java.lang.NoClassDefFoundError: gnu/io/SerialPortEventListener
        at org.eclipse.kura.binding.enocean.EnOcean.activate(EnOcean.java:27)
        ... 15 more
Caused by: java.lang.ClassNotFoundException: gnu.io.SerialPortEventListener
        at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:501)
        at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:421)
        at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:412)
        at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        ... 16 more
Root exception:
java.lang.NoClassDefFoundError: gnu/io/SerialPortEventListener
        at org.eclipse.kura.binding.enocean.EnOcean.activate(EnOcean.java:27)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.eclipse.equinox.internal.ds.model.ServiceComponent.activate(ServiceComponent.java:235)
        at org.eclipse.equinox.internal.ds.model.ServiceComponentProp.activate(ServiceComponentProp.java:146)
        at org.eclipse.equinox.internal.ds.model.ServiceComponentProp.build(ServiceComponentProp.java:347)
        at org.eclipse.equinox.internal.ds.InstanceProcess.buildComponent(InstanceProcess.java:620)
        at org.eclipse.equinox.internal.ds.InstanceProcess.buildComponents(InstanceProcess.java:197)
        at org.eclipse.equinox.internal.ds.Resolver.buildNewlySatisfied(Resolver.java:473)
        at org.eclipse.equinox.internal.ds.Resolver.enableComponents(Resolver.java:217)
        at org.eclipse.equinox.internal.ds.SCRManager.performWork(SCRManager.java:816)
        at org.eclipse.equinox.internal.ds.SCRManager$QueuedJob.dispatch(SCRManager.java:783)
        at org.eclipse.equinox.internal.ds.WorkThread.run(WorkThread.java:89)
        at org.eclipse.equinox.internal.util.impl.tpt.threadpool.Executor.run(Executor.java:70)
Caused by: java.lang.ClassNotFoundException: gnu.io.SerialPortEventListener
        at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:501)
        at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:421)
        at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:412)
        at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        ... 16 more

Updates: I tried a new approach, I copied the source file of the EnOcean library into my bundle, those sources uses the libary [2]Reflections

I warraped the library into a bundle (using eclipse: creating bundle from exiting archives) and I started it (the bundles starts with no error)

I imported the needed packages from the bundle Reflections but starting my bundle causes the same error but in the Reflections bundle

I started the bundle guava since it is the one causing the error but without success, I added the packages of the bundle guava[3] needed by the reflections as imported packages and again no success :( Here is the error:

Root exception:
java.lang.NoClassDefFoundError: com/google/common/collect/Lists
        at org.reflections.util.FilterBuilder.<init>(FilterBuilder.java:24)
        at org.reflections.scanners.SubTypesScanner.<init>(SubTypesScanner.java:19)
        at org.reflections.scanners.SubTypesScanner.<init>(SubTypesScanner.java:12)
        at org.reflections.util.ConfigurationBuilder.<init>(ConfigurationBuilder.java:53)
        at EnOcean.EEP.EEPRegistry.<init>(EEPRegistry.java:26)
        at EnOcean.EEP.EEPRegistry.getInstance(EEPRegistry.java:53)
        at EnOceanLibrary.communication.EnJConnection.initCommon(EnJConnection.java:205)
        at EnOceanLibrary.communication.EnJConnection.<init>(EnJConnection.java:154)
        at org.eclipse.kura.binding.enocean.EnOcean.activate(EnOcean.java:31)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.eclipse.equinox.internal.ds.model.ServiceComponent.activate(ServiceComponent.java:235)
        at org.eclipse.equinox.internal.ds.model.ServiceComponentProp.activate(ServiceComponentProp.java:146)
        at org.eclipse.equinox.internal.ds.model.ServiceComponentProp.build(ServiceComponentProp.java:347)
        at org.eclipse.equinox.internal.ds.InstanceProcess.buildComponent(InstanceProcess.java:620)
        at org.eclipse.equinox.internal.ds.InstanceProcess.buildComponents(InstanceProcess.java:197)
        at org.eclipse.equinox.internal.ds.Resolver.buildNewlySatisfied(Resolver.java:473)
        at org.eclipse.equinox.internal.ds.Resolver.enableComponents(Resolver.java:217)
        at org.eclipse.equinox.internal.ds.SCRManager.performWork(SCRManager.java:816)
        at org.eclipse.equinox.internal.ds.SCRManager$QueuedJob.dispatch(SCRManager.java:783)
        at org.eclipse.equinox.internal.ds.WorkThread.run(WorkThread.java:89)
        at org.eclipse.equinox.internal.util.impl.tpt.threadpool.Executor.run(Executor.java:70)

Thanks in advance for your help!

[1] https://github.com/dog-gateway/enj-library

[2] http://mvnrepository.com/artifact/org.reflections/reflections/0.9.9-RC2

[3] http://mvnrepository.com/artifact/com.google.guava/guava/15.0

Answer 1

The exception seems to be coming from the org.eclipse.kura.binding.enocean bundle, not from the EnJ-Library bundle.

Does org.eclipse.kura.binding.enocean import the package gnu.io?

Answer 2

@Neil Barlett: Thanks for your response!

Finally I added the reflections.jar in my libs directory and I added it in the Bundle class path. and I imported the com.google.common.collect in my bundle. and this time it worked, not sure if it is the best solution but it seems like when I wrap the reflections.jar in a bundle using eclipse it did not work properly.