/*
* Copyright 2010-2011 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.starflow.wf.engine.core.expression.aviator;
import java.util.Map;
import javax.script.Bindings;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.starflow.wf.engine.ScriptEngineConstants;
import com.starflow.wf.engine.core.expression.IExpressionHandler;
import com.starflow.wf.engine.core.expression.RuntimeExpressionException;
import com.starflow.wf.engine.model.elements.TransitionElement;
/**
*
* @author libinsong1204@gmail.com
* @date 2011-1-18 上午11:03:34
* @version
*/
abstract public class AbstractAviatorExpressionHandler implements IExpressionHandler {
protected final Logger logger = LoggerFactory.getLogger(getClass());
@Override
public boolean execute(ScriptEngineManager engineManager,
TransitionElement transition, Map<String, Object> conditions) {
ScriptEngine engine = engineManager.getEngineByName(ScriptEngineConstants.AVIATOR);
//创建执行表达式
String expression = buildExpression(transition, conditions);
if(logger.isDebugEnabled())
logger.debug("Transition Expressopn：{} Start", expression);
Bindings variables= engine.createBindings();
if(conditions != null) {
for (Map.Entry<String, Object> m : conditions.entrySet()) {
variables.put(m.getKey(), m.getValue());
if(logger.isDebugEnabled())
logger.debug(" Transition Condition：{} = {}", m.getKey(), m.getValue());
}
}
if(logger.isDebugEnabled())
logger.debug("Transition Expressopn End");
try {
Object result = engine.eval(expression, variables);
if(result instanceof Boolean && (Boolean)result) {
return true;
} else
return false;
} catch (Exception e) {
throw new RuntimeExpressionException("环节分支线表达式【"+expression+"】解析不正确", e);
}
}
abstract public String buildExpression(TransitionElement transition, Map<String, Object> conditions);
}