/*
* 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.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.context.Context;
import org.apache.avalon.framework.context.ContextException;
import org.apache.avalon.framework.context.Contextualizable;
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.forms.FormsConstants;
import org.apache.cocoon.forms.datatype.convertor.Convertor;
import org.apache.cocoon.forms.datatype.convertor.DefaultFormatCache;
import org.apache.cocoon.forms.datatype.convertor.ConversionResult;
import org.apache.cocoon.forms.util.DomHelper;
import org.apache.cocoon.util.Deprecation;
import org.apache.cocoon.util.location.LocationAttributes;
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
* <code>fd:selection-list</code> XML, so if anything changes here to how
* that XML is interpreted, it also needs to change over there and vice
* versa.</p>
*
* @version $Id$
*/
public class DefaultSelectionListBuilder implements SelectionListBuilder, Serviceable, Contextualizable {
private ServiceManager serviceManager;
private Context context;
public void contextualize(Context context) throws ContextException {
this.context = context;
}
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) {
// Principle of least surprise, use dynamic lists by default
boolean dynamic = true;
boolean usePerRequestCache = false;
String cacheType = DomHelper.getAttribute(selectionListElement, "cache", null);
// Read @cache
if ("request".equals(cacheType)) { // Dynamic SelectionList cached per request
dynamic = true;
usePerRequestCache = true;
} else if ("none".equals(cacheType)){ // Dynamic SelectionList non cached
dynamic = true;
} else if ("static".equals(cacheType)) {
// Static SelectionList
dynamic = false;
} else { // Checking for deprecated @dynamic
if (DomHelper.getAttribute(selectionListElement, "dynamic", null) != null) {
Deprecation.logger.warn("'@dynamic' is deprecated in <fd:selection-list> and replaced by '@cache' at " + DomHelper.getLocation(selectionListElement));
dynamic = DomHelper.getAttributeAsBoolean(selectionListElement, "dynamic", false);
}
}
// Create SelectionList
if (dynamic) {
selectionList = new DynamicSelectionList(datatype, src, usePerRequestCache, serviceManager, context);
} else {
selectionListElement = readSelectionList(src);
selectionList = buildStaticList(selectionListElement, datatype);
}
} 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();
// Remove location attributes from the selection list
LocationAttributes.remove(selectionListElement, true);
NodeList children = selectionListElement.getChildNodes();
for (int i = 0; children.item(i) != null; i++) {
Node node = children.item(i);
if (convertor == null && node instanceof Element && FormsConstants.DEFINITION_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 && FormsConstants.DEFINITION_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 {
ConversionResult conversionResult = convertor.convertFromString(stringValue, Locale.US, formatCache);
if (!conversionResult.isSuccessful()) {
throw new Exception("Could not convert the value \"" + stringValue +
"\" to the type " + datatype.getDescriptiveName() +
", defined at " + DomHelper.getLocation(element));
}
value = conversionResult.getResult();
}
XMLizable label = null;
Element labelEl = DomHelper.getChildElement(element, FormsConstants.DEFINITION_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, this.serviceManager);
Element selectionListElement = document.getDocumentElement();
if (!FormsConstants.DEFINITION_NS.equals(selectionListElement.getNamespaceURI()) ||
!"selection-list".equals(selectionListElement.getLocalName())) {
throw new Exception("Expected a fd:selection-list element at " +
DomHelper.getLocation(selectionListElement));
}
return selectionListElement;
} finally {
if (resolver != null) {
if (source != null) {
resolver.release(source);
}
serviceManager.release(resolver);
}
}
}
}