[rules-users] ClassNotFound on class defined in drl with 5.5.0.CR1

[Willem van Asperen]

Dear All,

I use the Drools compiler to compile a set of drl files:


         KnowledgeBuilder kbuilder = 
KnowledgeBuilderFactory.newKnowledgeBuilder(configuration);
         kbuilder.add(ResourceFactory.newFileResource(fileName), 
ResourceType.DRL);

         KnowledgeBuilderErrors errors = kbuilder.getErrors();
         if (errors.size() > 0) {
             for (KnowledgeBuilderError error: errors) {
                 logger.error(error);
             }
             throw new IllegalArgumentException("Could not parse 
knowledge.");
         }

         ObjectOutputStream out = new ObjectOutputStream(new 
FileOutputStream(fileName+".compiled"));
         out.writeObject( kbuilder.getKnowledgePackages());
         out.close();

I then load these *.compiled files into my application:


         for (String packageName : packages) {
             InputStream is = 
getClass().getResourceAsStream("/"+packageName+".drl.compiled");
             if (is != null) {
                 logger.debug("adding package '"+packageName+"'");
                 ObjectInputStream in = new ObjectInputStream(is);
kbase.addKnowledgePackages((Collection<KnowledgePackage>) in.readObject());
                 in.close();
             } else
                 throw new FileNotFoundException("could not find 
resource for package "+packageName);
             is.close();
         }

In some of these drl files I declare a class, for instance:

package vcm.selection.standard;

import com.paconsulting.pase.transport.agents.ShiftWorker;
import com.paconsulting.pase.transport.agents.VCMShiftWorker;
import com.paconsulting.pase.transport.actions.ExecutableAction;
import com.paconsulting.pase.transport.agents.ScheduleManagingContainer;
import com.paconsulting.pase.transport.agents.water.Bridge;
import com.paconsulting.pase.transport.agents.movers.AbstractMover;
import com.paconsulting.pase.transport.agents.movers.Ship;
import com.paconsulting.pase.transport.agents.movers.VCMShip;

declare RelevantExecutableAction
     agent : ShiftWorker
     executableAction : ExecutableAction
end
...

When running the 
kbase.addKnowledgePackages((Collection<KnowledgePackage>) 
in.readObject()) I get the following ClassNotFound stack trace:

java.lang.ClassNotFoundException: 
vcm.selection.standard.RelevantExecutableAction
     at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
     at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
     at java.security.AccessController.doPrivileged(Native Method)
     at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
     at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
     at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
     at java.lang.Class.forName0(Native Method)
     at java.lang.Class.forName(Class.java:264)
     at 
org.drools.common.DroolsObjectInputStream.resolveClass(DroolsObjectInputStream.java:85)
     at 
org.drools.common.DroolsObjectInputStream.resolveClass(DroolsObjectInputStream.java:97)
     at 
java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1593)
     at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1514)
     at java.io.ObjectInputStream.readClass(ObjectInputStream.java:1480)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1330)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at 
org.drools.rule.ConsequenceMetaData$Statement.readExternal(ConsequenceMetaData.java:61)
     at 
java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1810)
     at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1769)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at java.util.ArrayList.readObject(ArrayList.java:733)
     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:601)
     at 
java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1004)
     at 
java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1866)
     at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1771)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at 
org.drools.rule.ConsequenceMetaData.readExternal(ConsequenceMetaData.java:19)
     at 
java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1810)
     at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1769)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at org.drools.rule.Rule.readExternal(Rule.java:207)
     at 
java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1810)
     at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1769)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at 
org.drools.rule.JavaDialectRuntimeData.readExternal(JavaDialectRuntimeData.java:195)
     at 
java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1810)
     at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1769)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at java.util.HashMap.readObject(HashMap.java:1155)
     at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
     at 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:601)
     at 
java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1004)
     at 
java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1866)
     at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1771)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at 
org.drools.rule.DialectRuntimeRegistry.readExternal(DialectRuntimeRegistry.java:58)
     at 
java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1810)
     at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1769)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at org.drools.rule.Package.readExternal(Package.java:208)
     at 
org.drools.definitions.impl.KnowledgePackageImp.readExternal(KnowledgePackageImp.java:157)
     at 
java.io.ObjectInputStream.readExternalData(ObjectInputStream.java:1810)
     at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1769)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at java.util.ArrayList.readObject(ArrayList.java:733)
     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:601)
     at 
java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1004)
     at 
java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1866)
     at 
java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1771)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
     at 
com.paconsulting.pase.core.configuration.runconfig.definition.KnowledgebaseDefinition.addPackages(KnowledgebaseDefinition.java:48)
     at 
com.paconsulting.pase.core.configuration.runconfig.definition.KnowledgebaseDefinition.materialize(KnowledgebaseDefinition.java:59)
     at 
com.paconsulting.pase.core.configuration.runconfig.definition.TeamDefinition.materialize(TeamDefinition.java:97)
     at 
com.paconsulting.pase.core.configuration.runconfig.definition.OperatingModelDefinition.materialize(OperatingModelDefinition.java:36)
     at 
com.paconsulting.pase.core.configuration.runconfig.Run.<init>(Run.java:31)
     at 
com.paconsulting.pase.core.configuration.runconfig.definition.RunDefinition.materialize(RunDefinition.java:53)
     at 
com.paconsulting.pase.core.configuration.runconfig.RunConfigExecutor$ScheduleExecutorWrapper.run(RunConfigExecutor.java:69)
...

I'm sure I miss something as this is basic functionality. Maybe I must 
tell the kbase where to load the classes...

Can someone point me in the right direction?

Thanks,
Willem