Java tutorial
/******************************************************************************* * Copyright (c) 2010-2014 SAP AG and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * SAP AG - initial API and implementation *******************************************************************************/ package org.eclipse.skalli.view.internal.servlet; import java.io.File; import java.io.FileInputStream; import java.io.FilenameFilter; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.URL; import java.util.List; import java.util.Properties; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import javax.xml.transform.OutputKeys; import javax.xml.transform.Transformer; import javax.xml.transform.TransformerConfigurationException; import javax.xml.transform.TransformerException; import javax.xml.transform.TransformerFactory; import javax.xml.transform.dom.DOMSource; import javax.xml.transform.stream.StreamResult; import org.apache.commons.io.IOUtils; import org.apache.commons.lang.StringUtils; import org.apache.commons.lang.math.RandomUtils; import org.apache.commons.lang.text.StrSubstitutor; import org.eclipse.skalli.services.FilterMode; import org.eclipse.skalli.services.Services; import org.eclipse.skalli.services.extension.rest.RestUtils; import org.eclipse.skalli.view.Consts; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.xml.sax.InputSource; import org.xml.sax.SAXException; public class StaticContentServlet extends HttpServlet { private static final long serialVersionUID = -1552291510430177634L; private static final String BASE_DIR = "content"; private static final String TIP_OF_THE_DAY = "/tipoftheday"; private static final String TIP_PREFIX = "tip_"; private static final String TIP_SUFFIX = ".html"; public StaticContentServlet() { super(); } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String requestURI = request.getRequestURI(); if (requestURI.startsWith("/content/")) { String path = request.getPathInfo(); if (!path.startsWith("/")) { path = "/" + path; } InputStream in = getContent(path); if (in != null) { response.setContentType(getContentType(path)); try { OutputStream out = response.getOutputStream(); IOUtils.copy(in, out); } finally { IOUtils.closeQuietly(in); } return; } } else if (requestURI.startsWith("/schemas/")) { // otherwise check the bundles for a matching schema resource URL schema = RestUtils.findSchemaResource(requestURI); if (schema != null) { response.setContentType(getContentType(requestURI)); InputStream in = schema.openStream(); OutputStream out = response.getOutputStream(); try { resolveIncludes(in, out); } catch (Exception ex) { throw new IOException("Failed to resolve schema resource", ex); } finally { IOUtils.closeQuietly(in); } return; } } else if (requestURI.equals(Consts.URL_SEARCH_PLUGIN)) { URL searchPluginXML = getSearchPluginXML(); if (searchPluginXML != null) { response.setContentType("application/opensearchdescription+xml"); //$NON-NLS-1$ Properties properties = new Properties(); properties.put(Consts.ATTRIBUTE_SEARCH_PLUGIN_TITLE, request.getAttribute(Consts.ATTRIBUTE_SEARCH_PLUGIN_TITLE)); properties.put(Consts.ATTRIBUTE_SEARCH_PLUGIN_DESCRIPTION, request.getAttribute(Consts.ATTRIBUTE_SEARCH_PLUGIN_DESCRIPTION)); properties.put(Consts.ATTRIBUTE_WEBLOCATOR, StringUtils.removeEnd(request.getRequestURL().toString(), requestURI)); InputStream in = searchPluginXML.openStream(); try { String content = IOUtils.toString(in, "UTF-8"); //$NON-NLS-1$ StrSubstitutor subst = new StrSubstitutor(properties); content = subst.replace(content); OutputStream out = response.getOutputStream(); IOUtils.write(content, out, "UTF-8"); //$NON-NLS-1$ } finally { IOUtils.closeQuietly(in); } return; } } response.sendError(HttpServletResponse.SC_NOT_FOUND); } private URL getSearchPluginXML() { List<URL> urls = Services.findResources("/search", "search-plugin.xml", false, FilterMode.FIRST_MATCHING); return urls.size() == 1 ? urls.get(0) : null; } /** * Resolves all <include> in a given schema and writes the * result to the given output stream. Includes that can't be resolved * are removed from the schema. * @param in the input stream providing the schema to resolve. * @param out the output stream to write the result to. * @throws IOException if an i/o error occured. * @throws SAXException if parsing of the schema failed. * @throws ParserConfigurationException indicates a serious parser configuration error. * @throws TransformerException if transforming the schema DOM to a character stream failed. * @throws TransformerConfigurationException indicates a serious transformer configuration error. */ private void resolveIncludes(InputStream in, OutputStream out) throws IOException, SAXException, ParserConfigurationException, TransformerConfigurationException, TransformerException { DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); Document schemaDOM = dbf.newDocumentBuilder().parse(new InputSource(in)); Element schemaRoot = schemaDOM.getDocumentElement(); // iterate all <include> tags and resolve them if possible NodeList includes = schemaDOM.getElementsByTagName("xsd:include"); while (includes.getLength() > 0) { for (int i = 0; i < includes.getLength(); ++i) { Node includeNode = includes.item(i); Node includeParent = includeNode.getParentNode(); Node schemaLocation = includeNode.getAttributes().getNamedItem("schemaLocation"); if (schemaLocation != null) { // extract the pure file name from the schemaLocation and // try to find an XSD resource in all model extensions matching // the given schemaLocation attribute -> if found, replace the include tag // with the DOM of the include (without the root tag, of course!) URL includeFile = RestUtils.findSchemaResource(schemaLocation.getTextContent()); if (includeFile != null) { Document includeDOM = dbf.newDocumentBuilder() .parse(new InputSource(includeFile.openStream())); NodeList includeNodes = includeDOM.getDocumentElement().getChildNodes(); for (int j = 0; j < includeNodes.getLength(); ++j) { // import and insert the tag before <include> schemaRoot.insertBefore(schemaDOM.importNode(includeNodes.item(j), true), includeNode); } } // in any case: remove the <include> tag includeParent.removeChild(includeNode); } } // resolve includes of includes (if any) includes = schemaDOM.getElementsByTagName("xsd:include"); } // serialize the schema DOM to the given output stream Transformer xform = TransformerFactory.newInstance().newTransformer(); xform.setOutputProperty(OutputKeys.INDENT, "yes"); xform.setOutputProperty(OutputKeys.ENCODING, "UTF-8"); xform.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "no"); xform.transform(new DOMSource(schemaDOM), new StreamResult(out)); } private InputStream getContent(String path) throws IOException { if (TIP_OF_THE_DAY.equalsIgnoreCase(path)) { return getRandomFile(BASE_DIR + path, TIP_PREFIX, TIP_SUFFIX); } File f = new File(BASE_DIR + path); return f.exists() && f.isFile() ? new FileInputStream(f) : null; } private InputStream getRandomFile(String path, final String prefix, final String suffix) throws IOException { File dir = new File(path); File[] files = dir.listFiles(new FilenameFilter() { @Override public boolean accept(File dir, String name) { return name.startsWith(prefix) && name.endsWith(suffix); } }); if (files == null || files.length == 0) { return null; } int next = RandomUtils.nextInt(files.length); return new FileInputStream(files[next]); } private String getContentType(String path) { if (TIP_OF_THE_DAY.equalsIgnoreCase(path)) { return "text/html"; } else if (path.endsWith(".png")) { return "image/png"; } else if (path.endsWith(".gif")) { return "image/gif"; } else if (path.endsWith(".jpg") || path.endsWith(".jpeg")) { return "image/jpeg"; } else if (path.endsWith(".html") || path.endsWith(".html") || path.endsWith(".htmls")) { return "text/html"; } else if (path.endsWith(".css")) { return "text/css"; } else if (path.endsWith(".js")) { return "text/javascript"; } else if (path.endsWith(".xml") || path.endsWith(".xsd")) { return "text/xml"; } return "application/octet-stream"; } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse * response) */ @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { } }