NoClassDefFoundError in OSGi bundle on accessing standard java classes

Question

I' m trying to access an OSGI Bundle from my main application. But if a class in the bundle is accessed that uses javax.xml.* package. A NoClassDefFoundError is thrown.

java.lang.NoClassDefFoundError: javax/xml/transform/Source
    at de.foo.bar.test.Builder.<init>(Builder.java:46) ~[test-bundle-1.4.0.jar:1.4.0]
    at de.foo.bar.test.request.Factory.createRequest(Factory.java:99) ~[?:?]
    at de.foo.bar.test.request.Request.prepareRequest(Request.java:93) ~[?:?]
    at de.foo.bar.test.request.Request.process(Request.java:60) ~[?:?]
    at de.foo.bar.test.TestClass.execute(TestClass.java:74) ~[?:?]
    at de.foo.bar.test.TestClass.execute(TestClass.java:1) ~[?:?]
    at de.foo.bar.service.system.OsgiTransactionHandler.handleTransaction(OsgiTransactionHandler.java:71) ~[bin/:?]
    at de.foo.bar.service.system.TransactionRequestService.processTransaction(TransactionRequestService.java:110) ~[bin/:?]
    at de.foo.bar.service.system.TransactionRequestService.runService(TransactionRequestService.java:72) ~[bin/:?]
    at de.foo.bar.service.model.InfiniteService.run(InfiniteService.java:57) ~[bin/:?]
    at com.google.common.util.concurrent.AbstractExecutionThreadService$1$2.run(AbstractExecutionThreadService.java:60) [guava-16.0.1.jar:?]
    at com.google.common.util.concurrent.Callables$3.run(Callables.java:93) [guava-16.0.1.jar:?]
    at java.lang.Thread.run(Thread.java:662) [?:1.6.0_43]
Caused by: java.lang.ClassNotFoundException: javax.xml.transform.Source not found by test-bundle [1]
    at org.apache.felix.framework.BundleWiringImpl.findClassOrResourceByDelegation(BundleWiringImpl.java:1532) ~[org.apache.felix.framework-4.2.1.jar:?]
    at org.apache.felix.framework.BundleWiringImpl.access$400(BundleWiringImpl.java:75) ~[org.apache.felix.framework-4.2.1.jar:?]
    at org.apache.felix.framework.BundleWiringImpl$BundleClassLoader.loadClass(BundleWiringImpl.java:1955) ~[org.apache.felix.framework-4.2.1.jar:?]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247) ~[?:1.6.0_43]
    ... 13 more

I've checked the imported packages in the MANIFEST.MF and can see, that the package javax.xml.transform is stated (I've shortend it a bit):

Import-Package: com.fasterxml.jackson.core;resolution:=optional,com.fast
 ...
 500;resolution:=optional,javax.servlet;resolution:=optional,javax.sql;r
 esolution:=optional,javax.swing;resolution:=optional,javax.xml.bind;res
 olution:=optional,javax.xml.bind.annotation;resolution:=optional,javax.
 xml.bind.annotation.adapters;resolution:=optional,javax.xml.parsers;res
 olution:=optional,javax.xml.transform;resolution:=optional,javax.xml.tr
 ansform.stream;resolution:=optional,javax.xml.validation;resolution:=op
 tional,org.bson;resolution:=optional,org.lightcouch;resolution:=optiona
 l,org.osgi.framework;resolution:=optional;version="[1.5,2)",org.osgi.fr
 amework.wiring;resolution:=optional,org.w3c.dom;resolution:=optional,or
 g.xml.sax;resolution:=optional,sun.misc;resolution:=optional

I'm using apache felix in version 4.2.1 as an embedded framework and the maven-bundle-plugin is configured as follows:

<plugin>
    <groupId>org.apache.felix</groupId>
    <artifactId>maven-bundle-plugin</artifactId>
    <extensions>true</extensions>
    <configuration>
        <instructions>
            <Bundle-Name>Test Bundle</Bundle-Name>
            <Bundle-Activator>de.foo.bar.test.activator.TestActivator</Bundle-Activator>
            <Service-Component>OSGI-INF/component.xml</Service-Component>
            <Export-Package>de.foo.bar.test</Export-Package>
            <Bundle-SymbolicName>${project.artifactId}</Bundle-SymbolicName>
            <Import-Package>*;resolution:=optional</Import-Package>
            <Embed-Transitive>true</Embed-Transitive>
            <Embed-Dependency>*;scope=compile|runtime;inline=false;artifactId=!org.osgi.core</Embed-Dependency>
            <_failok>true</_failok>
            <_nouses>true</_nouses>
            <_nodefaultversion>true</_nodefaultversion>
            <_snapshot>${osgi-version-qualifier}</_snapshot>
        </instructions>
    </configuration>
</plugin>

I tried to export the missing packages by using FRAMEWORK_SYSTEMPACKAGES_EXTRA property. But that seems to result in exporting all Java packages. I've stopped it on the 7th package.

Is there a way to provide these java standard packages without exporting them explicitly?

Answer 1

The cause of this problem was located in the framework configuration. Based on an online tutorial I had added following parameter to my config:

config.put(Constants.FRAMEWORK_SYSTEMPACKAGES, "org.osgi.framework; version=1.5.0");

This caused that the default system packages have been replaced and only org.osgi.framework has been available besides the extra packages I exported.

After I'd removed this line the default packages where available again and so javax.xml.transform.