/*
* 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.datatype;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.w3c.dom.Node;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.avalon.framework.service.Serviceable;
import org.apache.cocoon.woody.Constants;
import org.apache.cocoon.woody.datatype.convertor.Convertor;
import org.apache.cocoon.woody.datatype.convertor.DefaultFormatCache;
import org.apache.cocoon.woody.util.DomHelper;
import org.apache.excalibur.source.Source;
import org.apache.excalibur.source.SourceResolver;
import org.apache.excalibur.xml.sax.XMLizable;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import java.util.Locale;
/**
* Builds {@link SelectionList}s from an XML description or an URL.
*
* <p>Note: the class {@link DynamicSelectionList} also interprets the same wd:selection-list XML, so if
* anything changes here to how that XML is interpreted, it also needs to change over there and vice versa.
*
* @version CVS $Id: DefaultSelectionListBuilder.java,v 1.6 2004/03/09 13:54:04 reinhard Exp $
*/
public class DefaultSelectionListBuilder implements SelectionListBuilder, Serviceable {
private ServiceManager serviceManager;
public void service(ServiceManager manager) throws ServiceException {
this.serviceManager = manager;
}
public SelectionList build(Element selectionListElement, Datatype datatype) throws Exception {
SelectionList selectionList;
String src = selectionListElement.getAttribute("src");
if (src.length() > 0) {
boolean dynamic = DomHelper.getAttributeAsBoolean(selectionListElement, "dynamic", false);
if (!dynamic) {
selectionListElement = readSelectionList(src);
selectionList = buildStaticList(selectionListElement, datatype);
} else {
selectionList = new DynamicSelectionList(datatype, src, serviceManager);
}
} else {
// selection list is defined inline
selectionList = buildStaticList(selectionListElement, datatype);
}
return selectionList;
}
private SelectionList buildStaticList(Element selectionListElement, Datatype datatype) throws Exception {
StaticSelectionList selectionList = new StaticSelectionList(datatype);
Convertor convertor = null;
Convertor.FormatCache formatCache = new DefaultFormatCache();
NodeList children = selectionListElement.getChildNodes();
for (int i = 0; children.item(i) != null; i++) {
Node node = children.item(i);
if (convertor == null && node instanceof Element && Constants.WD_NS.equals(node.getNamespaceURI()) && "convertor".equals(node.getLocalName())) {
Element convertorConfigElement = (Element)node;
try {
convertor = datatype.getBuilder().buildConvertor(convertorConfigElement);
} catch (Exception e) {
throw new SAXException("Error building convertor from convertor configuration embedded in selection list XML.", e);
}
} else if (node instanceof Element && Constants.WD_NS.equals(node.getNamespaceURI()) && "item".equals(node.getLocalName())) {
if (convertor == null) {
convertor = datatype.getConvertor();
}
Element element = (Element)node;
String stringValue = element.getAttribute("value");
Object value;
if ("".equals(stringValue)) {
// Empty value translates into the null object
value = null;
} else {
value = convertor.convertFromString(stringValue, Locale.US, formatCache);
if (value == null) {
throw new Exception("Could not convert the value \"" + stringValue +
"\" to the type " + datatype.getDescriptiveName() +
", defined at " + DomHelper.getLocation(element));
}
}
XMLizable label = null;
Element labelEl = DomHelper.getChildElement(element, Constants.WD_NS, "label");
if (labelEl != null) {
label = DomHelper.compileElementContent(labelEl);
}
selectionList.addItem(value, label);
}
}
return selectionList;
}
private Element readSelectionList(String src) throws Exception {
SourceResolver resolver = null;
Source source = null;
try {
resolver = (SourceResolver)serviceManager.lookup(SourceResolver.ROLE);
source = resolver.resolveURI(src);
InputSource inputSource = new InputSource(source.getInputStream());
inputSource.setSystemId(source.getURI());
Document document = DomHelper.parse(inputSource);
Element selectionListElement = document.getDocumentElement();
if (!Constants.WD_NS.equals(selectionListElement.getNamespaceURI()) || !"selection-list".equals(selectionListElement.getLocalName()))
throw new Exception("Excepted a wd:selection-list element at " + DomHelper.getLocation(selectionListElement));
return selectionListElement;
} finally {
if (source != null)
resolver.release(source);
if (resolver != null)
serviceManager.release(resolver);
}
}
}