/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.cocoon.forms.formmodel.algorithms;
import java.util.Iterator;
import java.util.List;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.cocoon.forms.expression.ExpressionManager;
import org.apache.cocoon.forms.formmodel.CalculatedFieldAlgorithm;
import org.apache.cocoon.forms.util.DomHelper;
import org.outerj.expression.Expression;
import org.outerj.expression.VariableFunction;
import org.w3c.dom.Element;
/**
* Builds a {@link org.apache.cocoon.forms.formmodel.algorithms.SimpleFormula}
* algorithm.
* <p>
* The syntax is as follows :
* <code>
* <fd:value type="formula" eval="..."> [triggers="..."]/>
* </code>
* </p>
* @version $Id: SimpleFormulaBuilder.java 449149 2006-09-23 03:58:05Z crossley $
*/
public class SimpleFormulaBuilder extends AbstractBaseAlgorithmBuilder {
private ExpressionManager expressionManager;
private ServiceManager serviceManager;
public CalculatedFieldAlgorithm build(Element algorithmElement) throws Exception {
String formula = DomHelper.getAttribute(algorithmElement, "eval");
SimpleFormula ret = new SimpleFormula();
setupExpression(formula, ret);
super.setup(algorithmElement, ret);
return ret;
}
protected Expression setupExpression(String formula) throws Exception {
return expressionManager.parse(formula);
}
protected void setupExpression(String formula, SimpleFormula algo) throws Exception {
Expression expression = expressionManager.parse(formula);
algo.setFormula(expression);
List vars = expressionManager.parseVariables(formula);
for (Iterator iter = vars.iterator(); iter.hasNext();) {
VariableFunction var = (VariableFunction) iter.next();
algo.addTrigger(var.getVariableName());
}
}
public void service(ServiceManager serviceManager) throws ServiceException {
this.serviceManager = serviceManager;
this.expressionManager = (ExpressionManager)serviceManager.lookup(ExpressionManager.ROLE);
}
public void dispose() {
this.serviceManager.release(this.expressionManager);
this.expressionManager = null;
this.serviceManager = null;
}
}