Java tutorial
/* * This library is part of OpenCms - * the Open Source Content Management System * * Copyright (c) Alkacon Software GmbH (http://www.alkacon.com) * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * For further information about Alkacon Software GmbH, please see the * company website: http://www.alkacon.com * * For further information about OpenCms, please see the * project website: http://www.opencms.org * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ package org.opencms.xml.page; import org.opencms.file.CmsFile; import org.opencms.file.CmsObject; import org.opencms.file.CmsPropertyDefinition; import org.opencms.file.CmsResource; import org.opencms.file.CmsResourceFilter; import org.opencms.file.types.CmsResourceTypeXmlContent; import org.opencms.file.types.CmsResourceTypeXmlPage; import org.opencms.i18n.CmsEncoder; import org.opencms.main.CmsException; import org.opencms.main.CmsLog; import org.opencms.main.OpenCms; import org.opencms.xml.CmsXmlEntityResolver; import org.opencms.xml.CmsXmlException; import org.opencms.xml.CmsXmlUtils; import org.opencms.xml.I_CmsXmlDocument; import org.opencms.xml.content.CmsXmlContentFactory; import org.opencms.xml.types.I_CmsXmlSchemaType; import java.io.UnsupportedEncodingException; import java.util.Locale; import javax.servlet.ServletRequest; import org.apache.commons.logging.Log; import org.dom4j.Document; import org.dom4j.DocumentHelper; import org.dom4j.Element; import org.xml.sax.EntityResolver; /** * Provides factory methods to unmarshal (read) an XML page object.<p> * * @since 6.0.0 */ public final class CmsXmlPageFactory { /** The log object for this class. */ private static final Log LOG = CmsLog.getLog(CmsXmlPageFactory.class); /** * No instances of this class should be created.<p> */ private CmsXmlPageFactory() { // noop } /** * Creates a valid XML page document, * containing one empty element in the given locale.<p> * * @param locale the locale to create the XML page for * * @return a valid XML page document */ public static Document createDocument(Locale locale) { Document doc = DocumentHelper.createDocument(); Element pages = doc.addElement(CmsXmlPage.NODE_PAGES); pages.add(I_CmsXmlSchemaType.XSI_NAMESPACE); pages.addAttribute(I_CmsXmlSchemaType.XSI_NAMESPACE_ATTRIBUTE_NO_SCHEMA_LOCATION, CmsXmlPage.XMLPAGE_XSD_SYSTEM_ID); Element page = pages.addElement(CmsXmlPage.NODE_PAGE); page.addAttribute(CmsXmlPage.ATTRIBUTE_LANGUAGE, locale.toString()); return doc; } /** * Creates a valid XML page String representation, * containing one empty element in the given locale.<p> * * @param locale the locale to create the XML page for * @param encoding the encoding to use when creating the String from the XML * * @return a valid XML page document as a String */ public static String createDocument(Locale locale, String encoding) { try { return CmsXmlUtils.marshal(createDocument(locale), encoding); } catch (CmsXmlException e) { // this should never happen LOG.error(Messages.get().getBundle().key(Messages.ERR_XML_PAGE_FACT_CREATE_DOC_0), e); return null; } } /** * Factory method to unmarshal (read) a XML page instance from a byte array * that contains XML data.<p> * * When unmarshalling, the encoding is read directly from the XML header. * The given encoding is used only when marshalling the XML again later.<p> * * @param xmlData the XML data in a byte array * @param encoding the encoding to use when marshalling the XML page later * @param resolver the XML entity resolver to use * * @return a XML page instance unmarshalled from the byte array * * @throws CmsXmlException if something goes wrong */ public static CmsXmlPage unmarshal(byte[] xmlData, String encoding, EntityResolver resolver) throws CmsXmlException { return new CmsXmlPage(CmsXmlUtils.unmarshalHelper(xmlData, resolver), encoding); } /** * Factory method to unmarshal (read) a XML page instance from a OpenCms VFS file * that contains XML data.<p> * * @param cms the current cms object * @param file the file with the XML data to unmarshal * * @return a XML page instance unmarshalled from the provided file * * @throws CmsXmlException if something goes wrong */ public static CmsXmlPage unmarshal(CmsObject cms, CmsFile file) throws CmsXmlException { return CmsXmlPageFactory.unmarshal(cms, file, true); } /** * Factory method to unmarshal (read) a XML page instance from a OpenCms VFS file * that contains XML data, using wither the encoding set * in the XML file header, or the encoding set in the VFS file property.<p> * * If you are not sure about the implications of the encoding issues, * use {@link #unmarshal(CmsObject, CmsFile)} instead.<p> * * @param cms the current OpenCms user context * @param file the file with the XML data to unmarshal * @param keepEncoding if true, the encoding spefified in the XML header is used, * otherwise the encoding from the VFS file property is used * * @return a XML page instance unmarshalled from the provided file * * @throws CmsXmlException if something goes wrong */ public static CmsXmlPage unmarshal(CmsObject cms, CmsFile file, boolean keepEncoding) throws CmsXmlException { byte[] content = file.getContents(); String fileName = cms.getSitePath(file); boolean allowRelative = false; try { allowRelative = Boolean .valueOf(cms.readPropertyObject(fileName, CmsXmlPage.PROPERTY_ALLOW_RELATIVE, false).getValue()) .booleanValue(); } catch (CmsException e) { // allowRelative will be false } String encoding = null; try { encoding = cms.readPropertyObject(fileName, CmsPropertyDefinition.PROPERTY_CONTENT_ENCODING, true) .getValue(); } catch (CmsException e) { // encoding will be null } if (encoding == null) { encoding = OpenCms.getSystemInfo().getDefaultEncoding(); } else { encoding = CmsEncoder.lookupEncoding(encoding, null); if (encoding == null) { throw new CmsXmlException( Messages.get().container(Messages.ERR_XML_PAGE_FACT_INVALID_ENC_1, fileName)); } } CmsXmlPage newPage; if (content.length > 0) { // content is initialized if (keepEncoding) { // use the encoding from the content newPage = unmarshal(content, encoding, new CmsXmlEntityResolver(cms)); } else { // use the encoding from the file property // this usually only triggered by a save operation try { String contentStr = new String(content, encoding); newPage = unmarshal(contentStr, encoding, new CmsXmlEntityResolver(cms)); } catch (UnsupportedEncodingException e) { // this will not happen since the encodig has already been validated throw new CmsXmlException( Messages.get().container(Messages.ERR_XML_PAGE_FACT_INVALID_ENC_1, fileName), e); } } } else { // content is empty newPage = new CmsXmlPage(cms.getRequestContext().getLocale(), encoding); } newPage.setFile(file); newPage.setAllowRelativeLinks(allowRelative); return newPage; } /** * Factory method to unmarshal (read) a XML page instance from * a resource, using the request attributes as cache.<p> * * @param cms the current OpenCms user context * @param resource the resource to unmarshal * @param req the current request * * @return the unmarshaled XML page, or null if the given resource was not of type {@link CmsResourceTypeXmlPage} * * @throws CmsException in something goes wrong */ public static CmsXmlPage unmarshal(CmsObject cms, CmsResource resource, ServletRequest req) throws CmsException { String rootPath = resource.getRootPath(); if (!CmsResourceTypeXmlPage.isXmlPage(resource)) { // sanity check: resource must be of type XML page throw new CmsXmlException(Messages.get().container(Messages.ERR_XML_PAGE_FACT_NO_XMLPAGE_TYPE_1, cms.getSitePath(resource))); } // try to get the requested page form the current request attributes CmsXmlPage page = (CmsXmlPage) req.getAttribute(rootPath); if (page == null) { // unmarshal XML structure from the file content page = unmarshal(cms, cms.readFile(resource)); // store the page that was read as request attribute for future read requests req.setAttribute(rootPath, page); } return page; } /** * Factory method to unmarshal (read) a XML document instance from * a filename in the VFS, using the request attributes as cache.<p> * * @param cms the current OpenCms user context * @param filename the filename of the resource to unmarshal * @param req the current request * * @return the unmarshaled XML document, or <code>null</code> if the given resource was not of type {@link I_CmsXmlDocument} * * @throws CmsException in something goes wrong */ public static I_CmsXmlDocument unmarshal(CmsObject cms, String filename, ServletRequest req) throws CmsException { // add site root to filename String rootPath = cms.getRequestContext().addSiteRoot(filename); // try to get the requested page form the current request attributes I_CmsXmlDocument doc = (I_CmsXmlDocument) req.getAttribute(rootPath); if (doc != null) { return doc; } // always use "ignore expiration" filter, date validity must be checked before calling this if required CmsFile file = cms.readFile(filename, CmsResourceFilter.IGNORE_EXPIRATION); if (CmsResourceTypeXmlPage.isXmlPage(file)) { // file is of type XML page doc = CmsXmlPageFactory.unmarshal(cms, file); } else if (CmsResourceTypeXmlContent.isXmlContent(file)) { // file is of type XML content doc = CmsXmlContentFactory.unmarshal(cms, file); } else { // sanity check: file type not an A_CmsXmlDocument throw new CmsXmlException(Messages.get().container(Messages.ERR_XML_PAGE_FACT_NO_XML_DOCUMENT_1, file)); } // store the page that was read as request attribute for future read requests req.setAttribute(rootPath, doc); return doc; } /** * Factory method to unmarshal (read) a XML page instance from a String * that contains XML data.<p> * * When unmarshalling, the encoding is read directly from the XML header. * The given encoding is used only when marshalling the XML again later.<p> * * @param xmlData the XML data in a String * @param encoding the encoding to use when marshalling the XML page later * @param resolver the XML entity resolver to use * * @return a XML page instance unmarshalled from the String * * @throws CmsXmlException if something goes wrong */ public static CmsXmlPage unmarshal(String xmlData, String encoding, EntityResolver resolver) throws CmsXmlException { return new CmsXmlPage(CmsXmlUtils.unmarshalHelper(xmlData, resolver), encoding); } }