/*
* Copyright 1999-2004 The Apache Software Foundation.
*
* 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.apache.cocoon.woody.formmodel;
import org.apache.cocoon.woody.Constants;
import org.apache.cocoon.woody.util.DomHelper;
import org.apache.excalibur.xml.sax.XMLizable;
import org.apache.oro.text.regex.MalformedPatternException;
import org.apache.oro.text.regex.Pattern;
import org.apache.oro.text.regex.Perl5Compiler;
import org.outerj.expression.Expression;
import org.w3c.dom.Element;
import java.util.HashSet;
/**
* Builds {@link AggregateFieldDefinition}s.
*
* @version $Id: AggregateFieldDefinitionBuilder.java,v 1.12 2004/03/09 13:53:56 reinhard Exp $
*/
public class AggregateFieldDefinitionBuilder extends FieldDefinitionBuilder {
public WidgetDefinition buildWidgetDefinition(Element widgetElement) throws Exception {
AggregateFieldDefinition aggregateDefinition = new AggregateFieldDefinition();
buildWidgetDefinition(aggregateDefinition, widgetElement);
// make children fields
Element widgetsElement = DomHelper.getChildElement(widgetElement, Constants.WD_NS, "widgets", true);
Element[] fieldElements = DomHelper.getChildElements(widgetsElement, Constants.WD_NS, "field");
for (int i = 0; i < fieldElements.length; i++) {
FieldDefinition fieldDefinition = (FieldDefinition)buildAnotherWidgetDefinition(fieldElements[i]);
aggregateDefinition.addWidgetDefinition(fieldDefinition);
}
// compile splitpattern
Element splitElement = DomHelper.getChildElement(widgetElement, Constants.WD_NS, "split", true);
String patternString = DomHelper.getAttribute(splitElement, "pattern");
Perl5Compiler compiler = new Perl5Compiler();
Pattern pattern = null;
try {
pattern = compiler.compile(patternString, Perl5Compiler.READ_ONLY_MASK);
} catch (MalformedPatternException e) {
throw new Exception("Invalid regular expression at " + DomHelper.getLocation(splitElement) + ": " + e.getMessage());
}
aggregateDefinition.setSplitPattern(pattern, patternString);
// read split mappings
Element[] mapElements = DomHelper.getChildElements(splitElement, Constants.WD_NS, "map");
HashSet encounteredFieldMappings = new HashSet();
for (int i = 0; i < mapElements.length; i++) {
int group = DomHelper.getAttributeAsInteger(mapElements[i], "group");
String field = DomHelper.getAttribute(mapElements[i], "field");
// check that this field exists
if (!aggregateDefinition.hasWidget(field)) {
throw new Exception("Unkwon widget id \"" + field + "\", at " +
DomHelper.getLocation(mapElements[i]));
}
if (encounteredFieldMappings.contains(field)) {
throw new Exception("Two groups are mapped to the same widget id \"" + field + "\", at " +
DomHelper.getLocation(mapElements[i]));
}
encounteredFieldMappings.add(field);
aggregateDefinition.addSplitMapping(group, field);
}
// read split fail message (if any)
Element failMessageElement = DomHelper.getChildElement(splitElement, Constants.WD_NS, "failmessage");
if (failMessageElement != null) {
XMLizable failMessage = DomHelper.compileElementContent(failMessageElement);
aggregateDefinition.setSplitFailMessage(failMessage);
}
// compile combine expression
Element combineElement = DomHelper.getChildElement(widgetElement, Constants.WD_NS, "combine", true);
String combineExprString = DomHelper.getAttribute(combineElement, "expression");
Expression combineExpr = null;
try {
combineExpr = expressionManager.parse(combineExprString);
} catch (Exception e) {
throw new Exception("Problem with combine expression defined at " +
DomHelper.getLocation(combineElement) + ": " + e.getMessage());
}
Class clazz = aggregateDefinition.getDatatype().getTypeClass();
if (combineExpr.getResultType() != null && !clazz.isAssignableFrom(combineExpr.getResultType())) {
throw new Exception("The result of the combine expression should be " + clazz.getName() + ", at " +
DomHelper.getLocation(combineElement));
}
aggregateDefinition.setCombineExpression(combineExpr);
return aggregateDefinition;
}
}