/*
* Copyright 2013 Red Hat, Inc. and/or its affiliates.
*
* 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 org.jbpm.process.core.transformation;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.drools.core.util.MVELSafeHelper;
import org.kie.api.runtime.process.DataTransformer;
import org.mvel2.MVEL;
import org.mvel2.ParserConfiguration;
import org.mvel2.ParserContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* MVEL based <code>DataTransformer</code> implementation
*
*/
public class MVELDataTransformer implements DataTransformer {
private static final Logger logger = LoggerFactory.getLogger(MVELDataTransformer.class);
@Override
public Object compile(String expression, Map<String, Object> parameters) {
logger.debug("About to compile mvel expression {}", expression);
ClassLoader classLoader = (ClassLoader) parameters.get("classloader");
if (classLoader == null) {
classLoader = this.getClass().getClassLoader();
}
ParserConfiguration config = new ParserConfiguration();
config.setClassLoader(classLoader);
ParserContext context = new ParserContext(config);
if (parameters != null) {
@SuppressWarnings("unchecked")
Set<String> imports = (Set<String>)parameters.get("imports");
if (imports != null) {
for(String clazz : imports) {
try {
Class<?> cl = Class.forName(clazz, true, classLoader);
context.addImport(cl.getSimpleName(), cl);
} catch (ClassNotFoundException e) {
logger.warn("Unable to load class {} due to {}", clazz, e.getException());
};
}
}
}
return MVEL.compileExpression(expression, context);
}
@Override
public Object transform(Object expression, Map<String, Object> parameters) {
logger.debug("About to execute mvel expression {} with parameters {}", expression, parameters);
return MVELSafeHelper.getEvaluator().executeExpression(expression, parameters);
}
}