[jboss-jira] [JBoss JIRA] Commented: (JBRULES-2312) java.lang.ClassCastException: org.drools.reteoo.BetaMemory cannot be cast to org.drools.reteoo.RuleTerminalNode$TerminalNodeMemory

java.lang.ClassCastException: org.drools.reteoo.BetaMemory cannot be cast to org.drools.reteoo.RuleTerminalNode$TerminalNodeMemory ---------------------------------------------------------------------------------------------------------------------------------- Key: JBRULES-2312 URL: https://jira.jboss.org/jira/browse/JBRULES-2312 Project: Drools Issue Type: Bug Security Level: Public(Everyone can see) Components: drools-core Affects Versions: 5.0.1.FINAL Environment: Linux 64-bit Reporter: nicholas hemley Assignee: Mark Proctor When removing packages from a knowledge base, the following intermittent error is encountered: java.lang.ClassCastException: org.drools.reteoo.BetaMemory cannot be cast to org.drools.reteoo.RuleTerminalNode$TerminalNodeMemory at org.drools.reteoo.RuleTerminalNode.doRemove(RuleTerminalNode.java:357) at org.drools.common.BaseNode.remove(BaseNode.java:95) at org.drools.reteoo.ReteooBuilder.removeRule(ReteooBuilder.java:237) at org.drools.reteoo.ReteooRuleBase.removeRule(ReteooRuleBase.java:366) at org.drools.common.AbstractRuleBase.removeRule(AbstractRuleBase.java:712) at org.drools.common.AbstractRuleBase.removePackage(AbstractRuleBase.java:640) at org.drools.impl.KnowledgeBaseImpl.removeKnowledgePackage(KnowledgeBaseImpl.java:166) The following JUnit code, which reads a dril file, adds packages to a knowledge base and then serialises/deserialises the knowledge packages before removing them, whilst not reproducing the issue, could be a useful starting point. It is currently considered that it is some combination of serialise and then add/remove package from a knowledge base that is causing the issue. import java.io.BufferedInputStream; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.net.URL; import java.util.ArrayList; import java.util.Collection; import java.util.Iterator; import java.util.List; import org.apache.log4j.BasicConfigurator; import org.apache.log4j.Logger; import org.drools.KnowledgeBase; import org.drools.KnowledgeBaseConfiguration; import org.drools.KnowledgeBaseFactory; import org.drools.builder.KnowledgeBuilder; import org.drools.builder.KnowledgeBuilderConfiguration; import org.drools.builder.KnowledgeBuilderError; import org.drools.builder.KnowledgeBuilderErrors; import org.drools.builder.KnowledgeBuilderFactory; import org.drools.builder.ResourceType; import org.drools.compiler.PackageBuilderConfiguration; import org.drools.definition.KnowledgePackage; import org.drools.io.Resource; import org.drools.io.ResourceFactory; import org.drools.rule.builder.dialect.java.JavaDialectConfiguration; import org.junit.Assert; import org.junit.Before; import org.junit.BeforeClass; import org.junit.Test; /** * test for a classcastexception issue when removing a knowledge package * */ public class DroolsJiraIssues { private static String filename = "ENTER DRL FILENAME HERE"; private static Logger log = Logger.getLogger(DroolsJiraIssues.class); private KnowledgeBaseConfiguration knowledgeBaseConfiguration = KnowledgeBaseFactory .newKnowledgeBaseConfiguration(); private KnowledgeBuilderConfiguration knowledgeBuilderConfiguration; @BeforeClass public static void beforeClass() { BasicConfigurator.configure(); } @Before public void setUp() { knowledgeBuilderConfiguration = KnowledgeBuilderFactory.newKnowledgeBuilderConfiguration(); JavaDialectConfiguration conf = (JavaDialectConfiguration) ((PackageBuilderConfiguration)knowledgeBuilderConfiguration).getDialectConfiguration("java"); conf.setCompiler(JavaDialectConfiguration.JANINO); } /** * remove knowledge packages sometimes throws the following error: * * java.lang.ClassCastException: org.drools.reteoo.BetaMemory cannot be cast to org.drools.reteoo.RuleTerminalNode$TerminalNodeMemory * at org.drools.reteoo.RuleTerminalNode.doRemove(RuleTerminalNode.java:357) * at org.drools.common.BaseNode.remove(BaseNode.java:95) * at org.drools.reteoo.ReteooBuilder.removeRule(ReteooBuilder.java:237) * at org.drools.reteoo.ReteooRuleBase.removeRule(ReteooRuleBase.java:366) * at org.drools.common.AbstractRuleBase.removeRule(AbstractRuleBase.java:712) * at org.drools.common.AbstractRuleBase.removePackage(AbstractRuleBase.java:640) * at org.drools.impl.KnowledgeBaseImpl.removeKnowledgePackage(KnowledgeBaseImpl.java:166) * */ @Test public void testRemoveKnowledgePackages() throws IOException { // create a knowledge base KnowledgeBase knowledgeBase = createKnowlegeBase(); // create knowledge packages from a .drl file Collection<KnowledgePackage> packages = readKnowledgePackagesFromFile(filename); log.info("packages.size() = " + packages.size()); // add all knowledge packages knowledgeBase.addKnowledgePackages(packages); log.info("added knowledge packages"); // remove all knowledge packages try { removePackagesForKnowledgeBase(knowledgeBase); } catch (ClassCastException e) { Assert.assertTrue(false); } log.info("removed knowledge packages"); // serialise and deserialise the knowledge packages Collection<KnowledgePackage> packages2 = null; try { packages2 = serialiseDeserialiseKnowledgePackages(packages); } catch (ClassNotFoundException e) { Assert.assertTrue(false); } Assert.assertTrue(packages2.size() == packages.size()); knowledgeBase.addKnowledgePackages(packages2); log.info("added serialised/deserialised knowledge packages"); // remove all knowledge packages try { removePackagesForKnowledgeBase(knowledgeBase); } catch (ClassCastException e) { Assert.assertTrue(false); } } private Collection<KnowledgePackage> serialiseDeserialiseKnowledgePackages(Collection<KnowledgePackage> packages) throws ClassNotFoundException, IOException { Collection<KnowledgePackage> packages2 = new ArrayList<KnowledgePackage>(); List<byte[]> serialisedPackageList = new ArrayList<byte[]>(); // serialize and deserialise knowledge packages by using a bytearrayoutputstream for (Iterator<KnowledgePackage> iter = packages.iterator(); iter.hasNext();) { KnowledgePackage kbPackage = iter.next(); ByteArrayOutputStream bos = new ByteArrayOutputStream(); ObjectOutputStream oos = new ObjectOutputStream(bos); oos.writeObject(kbPackage); log.info("wrote package name " + kbPackage.getName()); serialisedPackageList.add(bos.toByteArray()); } for (byte[] byteArray : serialisedPackageList) { ByteArrayInputStream bis = new ByteArrayInputStream(byteArray); ObjectInputStream ois = new ObjectInputStream(bis); KnowledgePackage kbPackage = (KnowledgePackage) ois.readObject(); log.info("read package name " + kbPackage.getName()); packages2.add(kbPackage); } return packages2; } /** * create a new knowledge base * * @return KnowledgeBase */ private KnowledgeBase createKnowlegeBase() { KnowledgeBase knowledgeBase = KnowledgeBaseFactory .newKnowledgeBase(knowledgeBaseConfiguration); return knowledgeBase; } /** * remove existing packages from a given knowledge base * * @param knowledgeBase */ private void removePackagesForKnowledgeBase(KnowledgeBase knowledgeBase) { Collection<KnowledgePackage> packages = knowledgeBase .getKnowledgePackages(); for (Iterator<KnowledgePackage> iter = packages.iterator(); iter .hasNext();) { KnowledgePackage kbPackage = iter.next(); String packageName = kbPackage.getName(); knowledgeBase.removeKnowledgePackage(packageName); log.info("removed packageName = " + packageName); } } private Collection<KnowledgePackage> readKnowledgePackagesFromFile( String filename) { Collection<KnowledgePackage> knowledgePackageList = new ArrayList<KnowledgePackage>(); URL fileUrl = TestTopologyServerImpl.class.getResource(filename); try { KnowledgeBuilder kbuilder = KnowledgeBuilderFactory .newKnowledgeBuilder(); Resource resource = ResourceFactory.newUrlResource(fileUrl); kbuilder.add(resource, ResourceType.DRL); if (kbuilder.hasErrors()) { KnowledgeBuilderErrors errors = kbuilder.getErrors(); Iterator<KnowledgeBuilderError> it = errors.iterator(); while (it.hasNext()) { KnowledgeBuilderError error = it.next(); log.error(error.getMessage()); } } Assert.assertTrue(!kbuilder.hasErrors()); knowledgePackageList = kbuilder.getKnowledgePackages(); } catch (Exception e) { log.error("error: " + e.getMessage()); } return knowledgePackageList; } /** * load a file * * @param file * @return * @throws IOException */ protected final String loadFileAsString(final File file) throws IOException { return new String(getFileAsBytes(file)); } /** * get the bytes of a file * * @param file * @return * @throws IOException */ private final byte[] getFileAsBytes(final File file) throws IOException { final BufferedInputStream bis = new BufferedInputStream( new FileInputStream(file)); final byte[] bytes = new byte[(int) file.length()]; bis.read(bytes); bis.close(); return bytes; } }