JBPM4.0源码以及分析

/* * JBoss, Home of Professional Open Source * Copyright 2005, JBoss Inc., and individual contributors as indicated * by the @authors tag. See the copyright.txt in the distribution for a * full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jbpm.pvm.internal.model; import java.io.Serializable; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; import java.util.Date; import java.util.HashMap; import java.util.HashSet; import java.util.LinkedHashSet; import java.util.LinkedList; import java.util.List; import java.util.Map; import java.util.Queue; import java.util.Set; import org.jbpm.api.Execution; import org.jbpm.api.JbpmException; import org.jbpm.api.activity.ActivityExecution; import org.jbpm.api.client.ClientProcessDefinition; import org.jbpm.api.client.ClientProcessInstance; import org.jbpm.api.env.Context; import org.jbpm.api.env.Environment; import org.jbpm.api.job.Timer; import org.jbpm.api.listener.EventListenerExecution; import org.jbpm.api.model.Activity; import org.jbpm.api.model.Comment; import org.jbpm.api.model.Event; import org.jbpm.api.model.ObservableElement; import org.jbpm.api.model.OpenExecution; import org.jbpm.api.model.Transition; import org.jbpm.internal.log.Log; import org.jbpm.pvm.internal.env.ExecutionContext; import org.jbpm.pvm.internal.history.HistoryEvent; import org.jbpm.pvm.internal.history.HistorySession; import org.jbpm.pvm.internal.history.events.ActivityEnd; import org.jbpm.pvm.internal.history.events.ActivityStart; import org.jbpm.pvm.internal.history.events.AutomaticEnd; import org.jbpm.pvm.internal.history.events.DecisionEnd; import org.jbpm.pvm.internal.history.events.ProcessInstanceEnd; import org.jbpm.pvm.internal.history.events.ProcessInstanceStart; import org.jbpm.pvm.internal.job.MessageImpl; import org.jbpm.pvm.internal.model.op.AtomicOperation; import org.jbpm.pvm.internal.model.op.MoveToChildActivity; import org.jbpm.pvm.internal.model.op.Signal; import org.jbpm.pvm.internal.session.DbSession; import org.jbpm.pvm.internal.session.MessageSession; import org.jbpm.pvm.internal.session.RepositorySession; import org.jbpm.pvm.internal.session.TimerSession; import org.jbpm.pvm.internal.type.Variable; import org.jbpm.pvm.internal.util.EqualsUtil; import org.jbpm.pvm.internal.util.Priority; /** * @author Tom Baeyens */ public class ExecutionImpl extends ScopeInstanceImpl implements ClientProcessInstance, ActivityExecution, EventListenerExecution, Serializable { private static final long serialVersionUID = 1L; private static final Log log = Log.getLog(Execution.class.getName()); /** * an optional name for this execution. can be used to differentiate * concurrent paths of execution like e.g. the 'shipping' and 'billing' * paths. */ protected String name; /** * a key for this execution. typically this is an externally provided * reference that is unique within the scope of the process definition. */ protected String key; /** a unique id for this execution. */ protected String id; /** are concurrent executions that related to this execution. */ protected Collection<ExecutionImpl> executions; /** * the parent child relation of executions is convenient for some forms of * concurrency. */ protected ExecutionImpl parent = null; protected ExecutionImpl processInstance; /** the super process link in case this is a sub process execution */ protected ExecutionImpl superProcessExecution; /** the sub process link in case of sub process execution */ protected ExecutionImpl subProcessInstance; /** the free text comments users make on this execution */ protected Set<CommentImpl> comments; /** reference to the current activity instance history record */ protected Long historyActivityInstanceDbid; /** start time of the activity for history purposes (not persisted) */ protected Date historyActivityStart; protected int priority = Priority.NORMAL; protected Map<String, Variable> systemVariables; // persistent indicators of the current position // //////////////////////////// /** persistent process definition reference */ protected String processDefinitionId; /** persistent activity reference */ protected String activityName; // transient cached indicators of the current position // ////////////////////// /** * transient cached process definition. persistence is managed in * {@link #processDefinitionId} */ protected ProcessDefinitionImpl processDefinition; /** * transient cached current activity pointer. persistence is managed in * {@link #activityName} */ private ActivityImpl activity; /** transition is not to be made persistable by default */ protected TransitionImpl transition; protected EventImpl event; protected AtomicOperation eventCompletedOperation; protected int eventListenerIndex; protected ObservableElementImpl eventSource; // cached named executions // ////////////////////////////////////////////////// /** * caches the child executions by execution name. This member might be null * and is only created from the executions in case its needed. Note that not * all executions are forced to have a name and duplicates are allowed. In * case the {@link #executions} change, the executionsMap can be nulled or * also updated (but a check needs to be added whether it exists). */ protected transient Map<String, Execution> executionsMap = null; /** the queue of atomic operations to be performed for this execution. */ protected Queue<AtomicOperation> atomicOperations; public enum Propagation { UNSPECIFIED, WAIT, EXPLICIT } protected Propagation propagation = null; // construction // ///////////////////////////////////////////////////////////// public void initializeProcessInstance( ProcessDefinitionImpl processDefinition, String key) { setProcessDefinition(processDefinition); setActivity((ActivityImpl) processDefinition.getInitial()); this.processInstance = this; this.state = STATE_CREATED; this.key = key; IdGenerator idGenerator = processDefinition.getIdGenerator(); if (idGenerator != null) { this.id = idGenerator.createId(processDefinition, null, this); } } // execution method : start // ///////////////////////////////////////////////// public void start() { if (state != STATE_CREATED) { throw new JbpmException(toString() + " is already begun: " + state); } this.state = STATE_ACTIVE_ROOT; ExecutionImpl scopedExecution = initializeScopes(); fireHistoryEvent(new ProcessInstanceStart()); fire(Event.START, getProcessDefinition()); if (getActivity() != null) { scopedExecution .performAtomicOperation(AtomicOperation.EXECUTE_ACTIVITY); } } protected ExecutionImpl initializeScopes() { LinkedList<ActivityImpl> enteredActivities = new LinkedList<ActivityImpl>(); ActivityImpl initial = getProcessDefinition().getInitial(); ExecutionImpl scopedExecution = null; if (initial != null) { enteredActivities.add(initial); ActivityImpl parentActivity = initial.getParentActivity(); while (parentActivity != null) { enteredActivities.addFirst(parentActivity); parentActivity = parentActivity.getParentActivity();