Invalid class load of embedded interface despite defined dependency ------------------------------------------------------------------- Key: WFLY-3511 URL: https://issues.jboss.org/browse/WFLY-3511 Project: WildFly Issue Type: Bug Components: Class Loading Affects Versions: 8.1.0.Final Reporter: Thomas Diesler Assignee: David Lloyd It is common that OSGi jars contain the interfaces of the services they implement. The wildfly modules hierarchy contains an implementation bundle for the HttpService with a dependency on org.osgi.enterprise which contains the org.osgi.service.http.HttpService interface. Client modules are expected to define a dependency on org.osgi.enterprise I would expect that org.osgi.service.http.HttpService is always loaded from org.osgi.enterprise and never from the impl bundle that also contains this interface. Module org.jboss.gravia contains the impl of the HttpService and a dependency on org.osgi.enterprise {code} <module xmlns="urn:jboss:module:1.1" name="org.jboss.gravia"> <properties> <property name="jboss.api" value="private"/> </properties> <resources> <resource-root path="gravia-provision-1.1.0.Beta30.jar"/> <resource-root path="gravia-repository-1.1.0.Beta30.jar"/> <resource-root path="gravia-resolver-1.1.0.Beta30.jar"/> <resource-root path="gravia-resource-1.1.0.Beta30.jar"/> <resource-root path="gravia-runtime-api-1.1.0.Beta30.jar"/> <resource-root path="gravia-runtime-embedded-1.1.0.Beta30.jar"/> <resource-root path="org.apache.felix.configadmin-1.8.0.jar"/> <resource-root path="org.apache.felix.http.bridge-2.2.1.jar"/> <resource-root path="org.apache.felix.log-1.0.1.jar"/> <resource-root path="org.apache.felix.metatype-1.0.8.jar"/> <resource-root path="org.apache.felix.scr-1.6.2.jar"/> </resources> <exports> <include path="org/jboss/gravia/process"/> <include path="org/jboss/gravia/provision"/> <include path="org/jboss/gravia/resource"/> <include path="org/jboss/gravia/resolver"/> <include path="org/jboss/gravia/repository"/> <include path="org/jboss/gravia/runtime"/> </exports> <dependencies> <module name="javax.api"/> <module name="javax.servlet.api"/> <module name="org.osgi.core"/> <module name="org.osgi.enterprise"/> <module name="org.slf4j"/> </dependencies> </module> {code} When I use this code in a webapp {code} ModuleClassLoader classLoader = (ModuleClassLoader) getClass().getClassLoader(); org.jboss.modules.Module graviaModule = loadModule(ModuleIdentifier.create("org.jboss.gravia")); org.jboss.modules.Module osgiModule = loadModule(ModuleIdentifier.create("org.osgi.enterprise")); Class<?> interfClass = loadClass(null, osgiModule.getClassLoader(), "org.osgi.service.http.HttpService"); Class<?> implClass = loadClass(null, graviaModule.getClassLoader(), "org.apache.felix.http.base.internal.service.HttpServiceImpl"); if (!interfClass.isAssignableFrom(implClass)) { System.out.println("NOT ASSIGNABLE: " + interfClass + " <= " + implClass); } {code} I get {code} 10:47:13,264 INFO [stdout] (MSC service thread 1-7) LOADED: interface org.osgi.service.http.HttpService 10:47:13,265 INFO [stdout] (MSC service thread 1-7) using null from ModuleClassLoader for Module "org.osgi.enterprise:main" from local module loader @10fdc382 (finder: local module finder @42e9485 (roots: /Users/tdiesler/git/fabric8poc/itests/smoke/wildfly/target/wildfly-8.1.0.Final/modules,/Users/tdiesler/git/fabric8poc/itests/smoke/wildfly/target/wildfly-8.1.0.Final/modules/system/layers/base)) 10:47:13,266 INFO [stdout] (MSC service thread 1-7) loaded from => ModuleClassLoader for Module "org.osgi.enterprise:main" from local module loader @10fdc382 (finder: local module finder @42e9485 (roots: /Users/tdiesler/git/fabric8poc/itests/smoke/wildfly/target/wildfly-8.1.0.Final/modules,/Users/tdiesler/git/fabric8poc/itests/smoke/wildfly/target/wildfly-8.1.0.Final/modules/system/layers/base)) 10:47:13,268 INFO [stdout] (MSC service thread 1-7) LOADED: class org.apache.felix.http.base.internal.service.HttpServiceImpl 10:47:13,268 INFO [stdout] (MSC service thread 1-7) using null from ModuleClassLoader for Module "org.jboss.gravia:main" from local module loader @10fdc382 (finder: local module finder @42e9485 (roots: /Users/tdiesler/git/fabric8poc/itests/smoke/wildfly/target/wildfly-8.1.0.Final/modules,/Users/tdiesler/git/fabric8poc/itests/smoke/wildfly/target/wildfly-8.1.0.Final/modules/system/layers/base)) 10:47:13,268 INFO [stdout] (MSC service thread 1-7) loaded from => ModuleClassLoader for Module "org.jboss.gravia:main" from local module loader @10fdc382 (finder: local module finder @42e9485 (roots: /Users/tdiesler/git/fabric8poc/itests/smoke/wildfly/target/wildfly-8.1.0.Final/modules,/Users/tdiesler/git/fabric8poc/itests/smoke/wildfly/target/wildfly-8.1.0.Final/modules/system/layers/base)) 10:47:13,269 INFO [stdout] (MSC service thread 1-7) NOT ASSIGNABLE: interface org.osgi.service.http.HttpService <= class org.apache.felix.http.base.internal.service.HttpServiceImpl {code} The resulting application error is {code} 10:47:13,503 WARN [org.jboss.gravia.runtime] (MSC service thread 1-7) Error while firing service event REGISTERED for: ServiceState{service.id=54, objectClass=[org.osgi.service.http.HttpService, org.apache.felix.http.api.ExtHttpService]}: java.lang.ClassCastException: org.apache.felix.http.base.internal.service.HttpServiceImpl cannot be cast to org.osgi.service.http.HttpService at org.jolokia.osgi.JolokiaActivator$HttpServiceCustomizer.addingService(JolokiaActivator.java:207) at org.osgi.util.tracker.ServiceTracker$Tracked.customizerAdding(ServiceTracker.java:932) [org.osgi.core-5.0.0.jar:] at org.osgi.util.tracker.ServiceTracker$Tracked.customizerAdding(ServiceTracker.java:864) [org.osgi.core-5.0.0.jar:] at org.osgi.util.tracker.AbstractTracked.trackAdding(AbstractTracked.java:256) [org.osgi.core-5.0.0.jar:] at org.osgi.util.tracker.AbstractTracked.track(AbstractTracked.java:229) [org.osgi.core-5.0.0.jar:] at org.osgi.util.tracker.ServiceTracker$Tracked.serviceChanged(ServiceTracker.java:894) [org.osgi.core-5.0.0.jar:] at org.jboss.gravia.runtime.embedded.spi.BundleContextAdaptor$ServiceListenerAdaptor.serviceChanged(BundleContextAdaptor.java:323) [gravia-runtime-embedded-1.1.0.Beta30.jar:] {code}