/*
* Copyright 2007-2009 非也
* All rights reserved.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation。
*
* This program 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 General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program. If not, see http://www.gnu.org/licenses.
*/
package org.fireflow.engine.kernelextensions;
import java.util.Map;
import org.fireflow.engine.EngineException;
import org.fireflow.engine.IRuntimeContextAware;
import org.fireflow.engine.RuntimeContext;
import org.fireflow.engine.condition.IConditionResolver;
import org.fireflow.engine.impl.ProcessInstanceTrace;
import org.fireflow.kernel.ILoopInstance;
import org.fireflow.kernel.IToken;
import org.fireflow.kernel.KernelException;
import org.fireflow.kernel.event.EdgeInstanceEvent;
import org.fireflow.kernel.event.IEdgeInstanceEventListener;
import org.fireflow.kernel.impl.LoopInstance;
import org.fireflow.kernel.plugin.IKernelExtension;
/**
*
* @author 非也
* @version 1.0 Created on Mar 18, 2009
*/
public class LoopInstanceExtension implements IKernelExtension,
IEdgeInstanceEventListener, IRuntimeContextAware {
protected RuntimeContext rtCtx = null;
public void setRuntimeContext(RuntimeContext ctx) {
this.rtCtx = ctx;
}
public RuntimeContext getRuntimeContext() {
return this.rtCtx;
}
public String getExtentionTargetName() {
return LoopInstance.Extension_Target_Name;
}
public String getExtentionPointName() {
return LoopInstance.Extension_Point_LoopInstanceEventListener;
}
/**
* @param vars
* @param condition
* @return
* @throws Exception
*/
private boolean determineTheAliveOfToken(Map<String ,Object> vars, String condition)
throws Exception {
// 通过计算transition上的表达式来确定alive的值
IConditionResolver elResolver = this.rtCtx.getConditionResolver();
Boolean b = elResolver.resolveBooleanExpression(vars, condition);
return b;
}
/**
* @param token
* @param condition
* @throws EngineException
*/
public void calculateTheAliveValue(IToken token, String condition)throws EngineException {
if (!token.isAlive()) {
return;// 如果token是dead状态，表明synchronizer的joinpoint是dead状态，不需要重新计算。
}
// 1、如果没有循环条件，默认为false
if (condition == null || condition.trim().equals("")) {
token.setAlive(false);
return;
}
// 3、计算EL表达式
try {
boolean alive = determineTheAliveOfToken(token.getProcessInstance()
.getProcessInstanceVariables(), condition);
token.setAlive(alive);
} catch (Exception ex) {
throw new EngineException(token.getProcessInstanceId(), token
.getProcessInstance().getWorkflowProcess(), token
.getNodeId(), ex.getMessage());
}
}
/* (non-Javadoc)
* @see org.fireflow.kernel.event.IEdgeInstanceEventListener#onEdgeInstanceEventFired(org.fireflow.kernel.event.EdgeInstanceEvent)
*/
public void onEdgeInstanceEventFired(EdgeInstanceEvent e)
throws KernelException {
if (e.getEventType() == EdgeInstanceEvent.ON_TAKING_THE_TOKEN) {
IToken token = e.getToken();
// 计算token的alive值
ILoopInstance transInst = (ILoopInstance) e.getSource();
String condition = transInst.getLoop().getCondition();
calculateTheAliveValue(token, condition);
if (rtCtx.isEnableTrace() && token.isAlive()) {
ProcessInstanceTrace trace = new ProcessInstanceTrace();
trace.setProcessInstanceId(e.getToken().getProcessInstanceId());
trace.setStepNumber(e.getToken().getStepNumber() + 1);
trace.setType(ProcessInstanceTrace.LOOP_TYPE);
trace.setFromNodeId(transInst.getLoop().getFromNode().getId());
trace.setToNodeId(transInst.getLoop().getToNode().getId());
trace.setEdgeId(transInst.getLoop().getId());
//TODO wmj2003 一旦token从当前边上经过，那么就保存流程运行轨迹,这里应该是insert
rtCtx.getPersistenceService().saveOrUpdateProcessInstanceTrace(
trace);
}
}
}
}