/**
* Copyright 2007-2008 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.ConditionConstant;
import org.fireflow.engine.condition.IConditionResolver;
import org.fireflow.engine.impl.ProcessInstanceTrace;
import org.fireflow.kernel.IToken;
import org.fireflow.kernel.ITransitionInstance;
import org.fireflow.kernel.KernelException;
import org.fireflow.kernel.event.EdgeInstanceEvent;
import org.fireflow.kernel.event.IEdgeInstanceEventListener;
import org.fireflow.kernel.impl.TransitionInstance;
import org.fireflow.kernel.plugin.IKernelExtension;
import org.fireflow.model.IWFElement;
import org.fireflow.model.net.Activity;
import org.fireflow.model.net.Transition;
/**
*
* @author chennieyun
*/
public class TransitionInstanceExtension implements IKernelExtension,
IEdgeInstanceEventListener, IRuntimeContextAware {
protected RuntimeContext rtCtx = null;
public void setRuntimeContext(RuntimeContext ctx) {
this.rtCtx = ctx;
}
public RuntimeContext getRuntimeContext() {
return this.rtCtx;
}
/**
* 执行分支判断策略，即设置token的alive属性 首先，如果this.alive==false,则所有的token的Alive属性皆为false
* 然后，如果在nexttransitionList中有值，则直接执行列表中的tansition
* 否则，通过计算Transition的表达式来确定下一个transition,
*
* @param transInst
* @return
*/
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;
}
/**
* 计算value值
* @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、如果没有转移条件，默认为true
if (condition == null || condition.trim().equals("")) {
token.setAlive(true);
return;
}
//2、default类型的不需要计算其alive值，该值由synchronizer决定
if (condition.trim().equals(ConditionConstant.DEFAULT)) {
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());
}
}
public String getExtentionTargetName() {
return TransitionInstance.Extension_Target_Name;
}
public String getExtentionPointName() {
return TransitionInstance.Extension_Point_TransitionInstanceEventListener;
}
/* (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();
ITransitionInstance transInst = (ITransitionInstance) e.getSource();
String condition = transInst.getTransition().getCondition();
calculateTheAliveValue(token, condition);
if (rtCtx.isEnableTrace() && token.isAlive()) {
Transition transition = transInst.getTransition();
IWFElement fromNode = transition.getFromNode();
int minorNumber = 1;
if (fromNode instanceof Activity){
minorNumber=2;
}else{
minorNumber =1;
}
ProcessInstanceTrace trace = new ProcessInstanceTrace();
trace.setProcessInstanceId(e.getToken().getProcessInstanceId());
trace.setStepNumber(e.getToken().getStepNumber());
trace.setType(ProcessInstanceTrace.TRANSITION_TYPE);
trace.setFromNodeId(transInst.getTransition().getFromNode().getId());
trace.setToNodeId(transInst.getTransition().getToNode().getId());
trace.setEdgeId(transInst.getTransition().getId());
trace.setMinorNumber(minorNumber);
//TODO wmj2003 这里应该是insert。一旦token从当前边上经过，那么就保存流程运行轨迹.
rtCtx.getPersistenceService().saveOrUpdateProcessInstanceTrace(trace);
}
}
}
}