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/* * Copyright 1999-2002,2004-2005 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.portal.transformation; import java.io.IOException; import java.util.ArrayList; import java.util.Enumeration; import java.util.List; import org.apache.cocoon.ProcessingException; import org.apache.cocoon.environment.wrapper.RequestParameters; import org.apache.cocoon.portal.LinkService; import org.apache.cocoon.portal.coplet.CopletInstanceData; import org.apache.cocoon.portal.event.impl.ChangeCopletInstanceAspectDataEvent; import org.apache.cocoon.portal.event.impl.CopletJXPathEvent; import org.apache.cocoon.portal.event.impl.JXPathEvent; import org.apache.cocoon.xml.AttributesImpl; import org.apache.cocoon.xml.XMLUtils; import org.apache.commons.jxpath.JXPathContext; import org.apache.excalibur.xml.sax.XMLizable; import org.xml.sax.Attributes; import org.xml.sax.SAXException; /** * This transformer offers various functions for developing pipeline based coplets. * * Includes coplet instance data by using JXPath expressions. * The transformer searches for tags <coplet:coplet xmlns:coplet="http://apache.org/cocoon/portal/coplet/1.0">. * They must have an attribute "select" that contains a valid JXPath expression applying to the coplet instance data.<br><br> * * Example:<br><br> * * <pre><maxpageable xmlns:coplet="http://apache.org/cocoon/portal/coplet/1.0"> * <coplet:coplet select="copletData.maxpageable"/> * </maxpageable><br></pre> * * The transformer will insert the boolean value specifying whether the coplet is * maxpageable or not.<br> * Please see also the documentation of superclass AbstractCopletTransformer for how * the coplet instance data are acquired. * * @author <a href="mailto:cziegeler@apache.org">Carsten Ziegeler</a> * @author <a href="mailto:bluetkemeier@s-und-n.de">Björn Lütkemeier</a> * @version CVS $Id: CopletTransformer.java 344185 2005-11-14 19:40:03Z cziegeler $ */ public class CopletTransformer extends AbstractCopletTransformer { /** * The namespace URI to listen for. */ public static final String NAMESPACE_URI = "http://apache.org/cocoon/portal/coplet/1.0"; /** * The XML element name to listen for. */ public static final String COPLET_ELEM = "coplet"; /** * The attribute containing the JXPath expression. */ public static final String SELECT_ATTR = "select"; /** * The XML element name to listen for. */ public static final String LINK_ELEM = "link"; /** Create a link containing several events */ public static final String LINKS_ELEM = "links"; /** Create a link containing several events */ public static final String PARAMETER_ELEM = "parameter"; /** The content for the links element */ public static final String CONTENT_ELEM = "content"; /** Are we inside a links element? */ protected boolean insideLinks; /** The collected list of events */ protected List collectedEvents = new ArrayList(); /** The content of the links */ protected XMLizable content; /** * Creates new CopletTransformer. */ public CopletTransformer() { this.defaultNamespaceURI = NAMESPACE_URI; } /* (non-Javadoc) * @see org.apache.cocoon.transformation.AbstractSAXTransformer#setupTransforming() */ public void setupTransforming() throws IOException, ProcessingException, SAXException { super.setupTransforming(); this.insideLinks = false; this.content = null; this.collectedEvents.clear(); } /** * Overridden from superclass. */ public void startTransformingElement(String uri, String name, String raw, Attributes attr) throws ProcessingException, IOException, SAXException { if (name.equals(COPLET_ELEM)) { String expression = attr.getValue(SELECT_ATTR); if (expression == null) { throw new ProcessingException("Attribute " + SELECT_ATTR + " must be spcified."); } final CopletInstanceData cid = this.getCopletInstanceData(); final JXPathContext jxpathContext = JXPathContext.newContext(cid); final Object object = jxpathContext.getValue(expression); if (object != null) { XMLUtils.valueOf(contentHandler, object); } } else if (name.equals(LINK_ELEM)) { final LinkService linkService = this.portalService.getComponentManager().getLinkService(); final String format = attr.getValue("format"); AttributesImpl newAttrs = new AttributesImpl(); newAttrs.setAttributes(attr); newAttrs.removeAttribute("format"); if (attr.getValue("href") != null) { final CopletInstanceData cid = this.getCopletInstanceData(); ChangeCopletInstanceAspectDataEvent event = new ChangeCopletInstanceAspectDataEvent(cid, null, null); String value = linkService.getLinkURI(event); if (value.indexOf('?') == -1) { value = value + '?' + attr.getValue("href"); } else { value = value + '&' + attr.getValue("href"); } newAttrs.removeAttribute("href"); this.output(value, format, newAttrs); } else { final String path = attr.getValue("path"); final String value = attr.getValue("value"); newAttrs.removeAttribute("path"); newAttrs.removeAttribute("value"); JXPathEvent event = null; if (attr.getValue("layout") != null) { newAttrs.removeAttribute("layout"); final String layoutId = attr.getValue("layout"); Object layout = this.portalService.getComponentManager().getProfileManager() .getPortalLayout(null, layoutId); if (layout != null) { event = new JXPathEvent(layout, path, value); } } else { String copletId = attr.getValue("coplet"); newAttrs.removeAttribute("coplet"); final CopletInstanceData cid = this.getCopletInstanceData(copletId); if (cid != null) { event = new CopletJXPathEvent(cid, path, value); } } if (this.insideLinks) { if (event != null) { this.collectedEvents.add(event); } } else { final String href = linkService.getLinkURI(event); this.output(href, format, newAttrs); } } } else if (name.equals(PARAMETER_ELEM)) { if (this.insideLinks) { String href = attr.getValue("href"); if (href != null) { final int pos = href.indexOf('?'); if (pos != -1) { href = href.substring(pos + 1); } this.collectedEvents.add(new LinkService.ParameterDescription(href)); } } } else if (name.equals(LINKS_ELEM)) { this.insideLinks = true; final AttributesImpl newAttrs = new AttributesImpl(); newAttrs.setAttributes(attr); newAttrs.removeAttribute("format"); this.stack.push(newAttrs); String format = attr.getValue("format"); if (format == null) { format = "html-link"; } this.stack.push(format); } else if (name.equals(CONTENT_ELEM) && this.insideLinks) { this.startSAXRecording(); } else { super.startTransformingElement(uri, name, raw, attr); } } /** * Overridden from superclass. */ public void endTransformingElement(String uri, String name, String raw) throws ProcessingException, IOException, SAXException { if (name.equals(LINK_ELEM)) { if (!this.insideLinks) { String elem = (String) this.stack.pop(); if (elem.length() > 0) { this.sendEndElementEvent(elem); } } } else if (name.equals(LINKS_ELEM)) { this.insideLinks = false; final String format = (String) this.stack.pop(); final LinkService linkService = this.portalService.getComponentManager().getLinkService(); String href = linkService.getLinkURI(this.collectedEvents); AttributesImpl newAttrs = (AttributesImpl) this.stack.pop(); // test for alternate base url final String baseURL = newAttrs.getValue("base-url"); if (baseURL != null) { newAttrs.removeAttribute("base-url"); int pos = href.indexOf('?') + 1; final char separator; if (baseURL.indexOf('?') == -1) { separator = '?'; } else { separator = '&'; } href = baseURL + separator + href.substring(pos); } this.output(href, format, newAttrs); this.collectedEvents.clear(); if (this.content != null) { this.content.toSAX(this.contentHandler); this.content = null; } String elem = (String) this.stack.pop(); if (elem.length() > 0) { this.sendEndElementEvent(elem); } } else if (name.equals(CONTENT_ELEM) && this.insideLinks) { this.content = this.endSAXRecording(); } else if (!name.equals(COPLET_ELEM) && !name.equals(PARAMETER_ELEM)) { super.endTransformingElement(uri, name, raw); } } /** * Output the link */ protected void output(String uri, String format, AttributesImpl newAttrs) throws SAXException { if (format == null) { // default format = "html-link"; } if ("html-link".equals(format)) { newAttrs.addCDATAAttribute("href", uri); this.sendStartElementEvent("a", newAttrs); this.stack.push("a"); } else if ("html-form".equals(format)) { boolean addParametersAsHiddenFields = false; String parameters = null; final String enctype = newAttrs.getValue("enctype"); if (enctype == null || "application/x-www-form-urlencoded".equalsIgnoreCase(enctype) || "multipart/form-data".equalsIgnoreCase(enctype)) { final int pos = uri.indexOf('?'); if (pos != -1) { parameters = uri.substring(pos + 1); uri = uri.substring(0, pos); addParametersAsHiddenFields = true; } } newAttrs.addCDATAAttribute("action", uri); this.sendStartElementEvent("form", newAttrs); this.stack.push("form"); if (addParametersAsHiddenFields) { // create hidden input fields RequestParameters pars = new RequestParameters(parameters); Enumeration enumeration = pars.getParameterNames(); while (enumeration.hasMoreElements()) { final String pName = (String) enumeration.nextElement(); final String[] pValues = pars.getParameterValues(pName); for (int k = 0; k < pValues.length; k++) { final String pValue = pValues[k]; AttributesImpl hiddenAttrs = new AttributesImpl(); hiddenAttrs.addCDATAAttribute("type", "hidden"); hiddenAttrs.addCDATAAttribute("name", pName); hiddenAttrs.addCDATAAttribute("value", pValue); this.startElement("", "input", "input", hiddenAttrs); this.endElement("", "input", "input"); } } } } else if ("text".equals(format)) { this.sendTextEvent(uri); this.stack.push(""); } else if ("parameters".equals(format)) { final String value = uri.substring(uri.indexOf('?') + 1); this.sendTextEvent(value); this.stack.push(""); } else { // own format newAttrs.addCDATAAttribute("href", uri); this.sendStartElementEvent("link", newAttrs); this.stack.push("link"); } } }