User: mnf999 Date: 01/08/01 12:03:27 Added: src/main/org/jboss/ejb/plugins EntityLockInterceptor.java Log: The entity lock interceptor. It is really a scheduler of threads. We use the beanlock from bill and create a brand new interceptor. The logic of the locking is implemented in the lock.schedule(mi) call Revision Changes Path 1.1 jboss/src/main/org/jboss/ejb/plugins/EntityLockInterceptor.java Index: EntityLockInterceptor.java =================================================================== /* * JBoss, the OpenSource EJB server * * Distributable under LGPL license. * See terms of license at gnu.org. */ package org.jboss.ejb.plugins; import java.lang.reflect.Method; import java.rmi.RemoteException; import java.util.Map; import java.util.HashMap; import java.util.ArrayList; import javax.ejb.EJBObject; import javax.ejb.CreateException; import javax.ejb.EJBException; import javax.ejb.NoSuchEntityException; import javax.ejb.RemoveException; import javax.ejb.EntityBean; import javax.transaction.Status; import javax.transaction.Synchronization; import javax.transaction.Transaction; import javax.transaction.TransactionManager; import javax.transaction.RollbackException; import javax.transaction.SystemException; import org.jboss.ejb.Container; import org.jboss.ejb.BeanLock; import org.jboss.ejb.BeanLockManager; import org.jboss.ejb.EntityContainer; import org.jboss.ejb.EntityPersistenceManager; import org.jboss.ejb.EntityEnterpriseContext; import org.jboss.ejb.EnterpriseContext; import org.jboss.ejb.InstanceCache; import org.jboss.ejb.InstancePool; import org.jboss.ejb.MethodInvocation; import org.jboss.ejb.CacheKey; import org.jboss.logging.log4j.JBossCategory; import org.jboss.metadata.EntityMetaData; import org.jboss.tm.TxManager; /** * The lock interceptors role is to schedule thread wanting to invoke method on a target bean * * <p>The policies for implementing scheduling (pessimistic locking etc) is implemented by pluggable * locks * * <p>We also implement serialization of calls in here (this is a spec * requirement). This is a fine grained notify, notifyAll mechanism. We * notify on ctx serialization locks and notifyAll on global transactional * locks. * * <p><b>WARNING: critical code</b>, get approval from senior developers * before changing. * * @author <a href="mailto:[EMAIL PROTECTED]";>Marc Fleury</a> * @author <a href="mailto:[EMAIL PROTECTED]";>Bill Burke</a> * @version $Revision: 1.1 $ * * <p><b>Revisions:</b><br> * <p><b>2001/07/30: marcf</b> * <ol> * <li>Initial revision * <li>Factorization of the lock out of the context in cache * <li>The new locking is implement as "scheduling" in the lock which allows for pluggable locks * </ol> */ public class EntityLockInterceptor extends AbstractInterceptor { // Constants ----------------------------------------------------- // Attributes ---------------------------------------------------- protected EntityContainer container; // Static -------------------------------------------------------- /** Use a JBoss custom log4j category for trace level logging */ static JBossCategory log = (JBossCategory) JBossCategory.getInstance(EntityInstanceInterceptor.class); // Constructors -------------------------------------------------- // Public -------------------------------------------------------- public void setContainer(Container container) { this.container = (EntityContainer)container; } public Container getContainer() { return container; } // Interceptor implementation -------------------------------------- public Object invokeHome(MethodInvocation mi) throws Exception { // Invoke through interceptors return getNext().invokeHome(mi); } public Object invoke(MethodInvocation mi) throws Exception { // The key. Object key = (CacheKey) mi.getId(); // The lock. BeanLock lock ; boolean threadIsScheduled = false; boolean trace = log.isTraceEnabled(); if( trace ) log.trace("Begin invoke, key="+key); try { lock = (BeanLock)container.getLockManager().getLock(key); while (!threadIsScheduled) { if( trace ) log.trace("new while(threadNotScheduled) for key"+key); /** * schedule will implement the actual lock policy in the lock * we provide a default "pessimistic lock" on the transaction * as well as the default serialization required by the specification * the method releases the sync if the thread isn't scheduled and goes to wait * upon waking up it must go through the schedule again */ threadIsScheduled = lock.schedule(mi); } try { return getNext().invoke(mi); } finally { // we are done with the method, decrease the count, if it reaches 0 it will wake up // the next thread lock.sync(); lock.releaseMethodLock(); lock.releaseSync(); } } finally { // We are done with the lock in general container.getLockManager().removeLockRef(key); if( trace ) log.trace("End invoke, key="+key); } } } _______________________________________________ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development
