Java tutorial
package com.liferay.lms.servlet; import java.io.Closeable; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.OutputStream; import java.io.RandomAccessFile; import java.io.UnsupportedEncodingException; import java.net.URLDecoder; import java.security.Key; import java.util.ArrayList; import java.util.Arrays; import java.util.List; import java.util.ListIterator; import java.util.zip.GZIPOutputStream; import javax.servlet.ServletException; import javax.servlet.ServletOutputStream; import javax.servlet.http.Cookie; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.xml.parsers.DocumentBuilderFactory; import org.apache.commons.io.FileUtils; import com.liferay.lms.learningactivity.LearningActivityType; import com.liferay.lms.learningactivity.SCORMLearningActivityType; import com.liferay.lms.model.LearningActivity; import com.liferay.lms.model.SCORMContent; import com.liferay.lms.service.LearningActivityLocalServiceUtil; import com.liferay.lms.service.SCORMContentLocalServiceUtil; import com.liferay.portal.kernel.util.GetterUtil; import com.liferay.portal.kernel.util.ListUtil; import com.liferay.portal.kernel.util.MimeTypesUtil; import com.liferay.portal.kernel.util.ParamUtil; import com.liferay.portal.kernel.util.Validator; import com.liferay.portal.kernel.xml.Document; import com.liferay.portal.kernel.xml.Element; import com.liferay.portal.kernel.xml.Node; import com.liferay.portal.kernel.xml.SAXReaderUtil; import com.liferay.portal.model.Company; import com.liferay.portal.model.User; import com.liferay.portal.security.permission.ActionKeys; import com.liferay.portal.security.permission.PermissionChecker; import com.liferay.portal.security.permission.PermissionCheckerFactoryUtil; import com.liferay.portal.service.CompanyLocalServiceUtil; import com.liferay.portal.service.UserLocalServiceUtil; import com.liferay.portal.util.PortalUtil; import com.liferay.portlet.asset.model.AssetEntry; import com.liferay.portlet.asset.service.AssetEntryLocalServiceUtil; import com.liferay.util.Encryptor; /** * Servlet implementation class SCORMFileServerServlet * * Part of this code was copied from: * net/balusc/webapp/FileServlet.java * Hopefully has exactly the same License that Wemooc. * * * * Copyright (C) 2009 BalusC * * This program 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 3 * 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. * * You should have received a copy of the GNU Lesser General Public License along with this library. * If not, see <http://www.gnu.org/licenses/>. * net/balusc/webapp/FileServlet.java * * Copyright (C) 2009 BalusC * * This program 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 3 * 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. * * You should have received a copy of the GNU Lesser General Public License along with this library. * If not, see <http://www.gnu.org/licenses/>. */ public class SCORMFileServerServlet extends HttpServlet { private static final int DEFAULT_BUFFER_SIZE = 10240; // ..bytes = 10KB. private static final long DEFAULT_EXPIRE_TIME = 604800000L; // ..ms = 1 week. private static final String MULTIPART_BOUNDARY = "MULTIPART_BYTERANGES"; private static final long serialVersionUID = 1L; private String hexStringToStringByAscii(String hexString) { byte[] bytes = new byte[hexString.length() / 2]; for (int i = 0; i < hexString.length() / 2; i++) { String oneHexa = hexString.substring(i * 2, i * 2 + 2); bytes[i] = Byte.parseByte(oneHexa, 16); } try { return new String(bytes, "ASCII"); } catch (UnsupportedEncodingException e) { throw new RuntimeException(e); } } protected void doHead(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // Process request without content. processRequest(request, response, false); } /** * Procesa los metodos HTTP GET y POST.<br> * Busca en la ruta que se le ha pedido el comienzo del directorio * "contenidos" y sirve el fichero. */ protected void processRequest(HttpServletRequest request, HttpServletResponse response, boolean content) throws ServletException, java.io.IOException { String mime_type; String charset; String patharchivo; String uri; try { User user = PortalUtil.getUser(request); if (user == null) { String userId = null; String companyId = null; Cookie[] cookies = ((HttpServletRequest) request).getCookies(); if (Validator.isNotNull(cookies)) { for (Cookie c : cookies) { if ("COMPANY_ID".equals(c.getName())) { companyId = c.getValue(); } else if ("ID".equals(c.getName())) { userId = hexStringToStringByAscii(c.getValue()); } } } if (userId != null && companyId != null) { try { Company company = CompanyLocalServiceUtil.getCompany(Long.parseLong(companyId)); Key key = company.getKeyObj(); String userIdPlain = Encryptor.decrypt(key, userId); user = UserLocalServiceUtil.getUser(Long.valueOf(userIdPlain)); // Now you can set the liferayUser into a thread local // for later use or // something like that. } catch (Exception pException) { throw new RuntimeException(pException); } } } String rutaDatos = SCORMContentLocalServiceUtil.getBaseDir(); // Se comprueba que el usuario tiene permisos para acceder. // Damos acceso a todo el mundo al directorio "personalizacion", // para permitir mostrar a todos la pantalla de identificacion. uri = URLDecoder.decode(request.getRequestURI(), "UTF-8"); uri = uri.substring(uri.indexOf("scorm/") + "scorm/".length()); patharchivo = rutaDatos + "/" + uri; String[] params = uri.split("/"); long groupId = GetterUtil.getLong(params[1]); String uuid = params[2]; SCORMContent scormContent = SCORMContentLocalServiceUtil.getSCORMContentByUuidAndGroupId(uuid, groupId); boolean allowed = false; if (user == null) { user = UserLocalServiceUtil.getDefaultUser(PortalUtil.getDefaultCompanyId()); } PermissionChecker pc = PermissionCheckerFactoryUtil.create(user); allowed = pc.hasPermission(groupId, SCORMContent.class.getName(), scormContent.getScormId(), ActionKeys.VIEW); if (!allowed) { AssetEntry scormAsset = AssetEntryLocalServiceUtil.getEntry(SCORMContent.class.getName(), scormContent.getPrimaryKey()); long scormAssetId = scormAsset.getEntryId(); int typeId = new Long((new SCORMLearningActivityType()).getTypeId()).intValue(); long[] groupIds = user.getGroupIds(); for (long gId : groupIds) { List<LearningActivity> acts = LearningActivityLocalServiceUtil .getLearningActivitiesOfGroupAndType(gId, typeId); for (LearningActivity act : acts) { String entryId = LearningActivityLocalServiceUtil.getExtraContentValue(act.getActId(), "assetEntry"); if (Validator.isNotNull(entryId) && Long.valueOf(entryId) == scormAssetId) { allowed = pc.hasPermission(gId, LearningActivity.class.getName(), act.getActId(), ActionKeys.VIEW); if (allowed) { break; } } } if (allowed) { break; } } } if (allowed) { File archivo = new File(patharchivo); // Si el archivo existe y no es un directorio se sirve. Si no, // no se hace nada. if (archivo.exists() && archivo.isFile()) { // El content type siempre antes del printwriter mime_type = MimeTypesUtil.getContentType(archivo); charset = ""; if (archivo.getName().toLowerCase().endsWith(".html") || archivo.getName().toLowerCase().endsWith(".htm")) { mime_type = "text/html"; if (isISO(FileUtils.readFileToString(archivo))) { charset = "ISO-8859-1"; } } if (archivo.getName().toLowerCase().endsWith(".swf")) { mime_type = "application/x-shockwave-flash"; } if (archivo.getName().toLowerCase().endsWith(".mp4")) { mime_type = "video/mp4"; } if (archivo.getName().toLowerCase().endsWith(".flv")) { mime_type = "video/x-flv"; } response.setContentType(mime_type); if (Validator.isNotNull(charset)) { response.setCharacterEncoding(charset); } response.addHeader("Content-Type", mime_type + (Validator.isNotNull(charset) ? "; " + charset : "")); /*if (archivo.getName().toLowerCase().endsWith(".swf") || archivo.getName().toLowerCase().endsWith(".flv")) { response.addHeader("Content-Length", String.valueOf(archivo.length())); } */ if (archivo.getName().toLowerCase().endsWith("imsmanifest.xml")) { FileInputStream fis = new FileInputStream(patharchivo); String sco = ParamUtil.get(request, "scoshow", ""); Document manifest = SAXReaderUtil.read(fis); if (sco.length() > 0) { Element organizatEl = manifest.getRootElement().element("organizations") .element("organization"); Element selectedItem = selectItem(organizatEl, sco); if (selectedItem != null) { selectedItem.detach(); java.util.List<Element> items = organizatEl.elements("item"); for (Element item : items) { organizatEl.remove(item); } organizatEl.add(selectedItem); } } //clean unused resources. Element resources = manifest.getRootElement().element("resources"); java.util.List<Element> theResources = resources.elements("resource"); Element organizatEl = manifest.getRootElement().element("organizations") .element("organization"); java.util.List<String> identifiers = getIdentifierRefs(organizatEl); for (Element resource : theResources) { String identifier = resource.attributeValue("identifier"); if (!identifiers.contains(identifier)) { resources.remove(resource); } } response.getWriter().print(manifest.asXML()); fis.close(); return; } if (mime_type.startsWith("text") || mime_type.endsWith("javascript") || mime_type.equals("application/xml")) { java.io.OutputStream out = response.getOutputStream(); FileInputStream fis = new FileInputStream(patharchivo); byte[] buffer = new byte[512]; int i = 0; while (fis.available() > 0) { i = fis.read(buffer); if (i == 512) out.write(buffer); else out.write(buffer, 0, i); } fis.close(); out.flush(); out.close(); return; } //If not manifest String fileName = archivo.getName(); long length = archivo.length(); long lastModified = archivo.lastModified(); String eTag = fileName + "_" + length + "_" + lastModified; long expires = System.currentTimeMillis() + DEFAULT_EXPIRE_TIME; String ifNoneMatch = request.getHeader("If-None-Match"); if (ifNoneMatch != null && matches(ifNoneMatch, eTag)) { response.setStatus(HttpServletResponse.SC_NOT_MODIFIED); response.setHeader("ETag", eTag); // Required in 304. response.setDateHeader("Expires", expires); // Postpone cache with 1 week. return; } long ifModifiedSince = request.getDateHeader("If-Modified-Since"); if (ifNoneMatch == null && ifModifiedSince != -1 && ifModifiedSince + 1000 > lastModified) { response.setStatus(HttpServletResponse.SC_NOT_MODIFIED); response.setHeader("ETag", eTag); // Required in 304. response.setDateHeader("Expires", expires); // Postpone cache with 1 week. return; } // If-Match header should contain "*" or ETag. If not, then return 412. String ifMatch = request.getHeader("If-Match"); if (ifMatch != null && !matches(ifMatch, eTag)) { response.sendError(HttpServletResponse.SC_PRECONDITION_FAILED); return; } // If-Unmodified-Since header should be greater than LastModified. If not, then return 412. long ifUnmodifiedSince = request.getDateHeader("If-Unmodified-Since"); if (ifUnmodifiedSince != -1 && ifUnmodifiedSince + 1000 <= lastModified) { response.sendError(HttpServletResponse.SC_PRECONDITION_FAILED); return; } // Validate and process range ------------------------------------------------------------- // Prepare some variables. The full Range represents the complete file. Range full = new Range(0, length - 1, length); List<Range> ranges = new ArrayList<Range>(); // Validate and process Range and If-Range headers. String range = request.getHeader("Range"); if (range != null) { // Range header should match format "bytes=n-n,n-n,n-n...". If not, then return 416. if (!range.matches("^bytes=\\d*-\\d*(,\\d*-\\d*)*$")) { response.setHeader("Content-Range", "bytes */" + length); // Required in 416. response.sendError(HttpServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE); return; } // If-Range header should either match ETag or be greater then LastModified. If not, // then return full file. String ifRange = request.getHeader("If-Range"); if (ifRange != null && !ifRange.equals(eTag)) { try { long ifRangeTime = request.getDateHeader("If-Range"); // Throws IAE if invalid. if (ifRangeTime != -1 && ifRangeTime + 1000 < lastModified) { ranges.add(full); } } catch (IllegalArgumentException ignore) { ranges.add(full); } } // If any valid If-Range header, then process each part of byte range. if (ranges.isEmpty()) { for (String part : range.substring(6).split(",")) { // Assuming a file with length of 100, the following examples returns bytes at: // 50-80 (50 to 80), 40- (40 to length=100), -20 (length-20=80 to length=100). long start = sublong(part, 0, part.indexOf("-")); long end = sublong(part, part.indexOf("-") + 1, part.length()); if (start == -1) { start = length - end; end = length - 1; } else if (end == -1 || end > length - 1) { end = length - 1; } // Check if Range is syntactically valid. If not, then return 416. if (start > end) { response.setHeader("Content-Range", "bytes */" + length); // Required in 416. response.sendError(HttpServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE); return; } // Add range. ranges.add(new Range(start, end, length)); } } } boolean acceptsGzip = false; String disposition = "inline"; if (mime_type.startsWith("text")) { //String acceptEncoding = request.getHeader("Accept-Encoding"); // acceptsGzip = acceptEncoding != null && accepts(acceptEncoding, "gzip"); // mime_type += ";charset=UTF-8"; } // Else, expect for images, determine content disposition. If content type is supported by // the browser, then set to inline, else attachment which will pop a 'save as' dialogue. else if (!mime_type.startsWith("image")) { String accept = request.getHeader("Accept"); disposition = accept != null && accepts(accept, mime_type) ? "inline" : "attachment"; } // Initialize response. response.reset(); response.setBufferSize(DEFAULT_BUFFER_SIZE); response.setHeader("Content-Disposition", disposition + ";filename=\"" + fileName + "\""); response.setHeader("Accept-Ranges", "bytes"); response.setHeader("ETag", eTag); response.setDateHeader("Last-Modified", lastModified); response.setDateHeader("Expires", expires); // Send requested file (part(s)) to client ------------------------------------------------ // Prepare streams. RandomAccessFile input = null; OutputStream output = null; try { // Open streams. input = new RandomAccessFile(archivo, "r"); output = response.getOutputStream(); if (ranges.isEmpty() || ranges.get(0) == full) { // Return full file. Range r = full; response.setContentType(mime_type); response.setHeader("Content-Range", "bytes " + r.start + "-" + r.end + "/" + r.total); if (content) { // Content length is not directly predictable in case of GZIP. // So only add it if there is no means of GZIP, else browser will hang. response.setHeader("Content-Length", String.valueOf(r.length)); // Copy full range. copy(input, output, r.start, r.length); } } else if (ranges.size() == 1) { // Return single part of file. Range r = ranges.get(0); response.setContentType(mime_type); response.setHeader("Content-Range", "bytes " + r.start + "-" + r.end + "/" + r.total); response.setHeader("Content-Length", String.valueOf(r.length)); response.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT); // 206. if (content) { // Copy single part range. copy(input, output, r.start, r.length); } } else { // Return multiple parts of file. response.setContentType("multipart/byteranges; boundary=" + MULTIPART_BOUNDARY); response.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT); // 206. if (content) { // Cast back to ServletOutputStream to get the easy println methods. ServletOutputStream sos = (ServletOutputStream) output; // Copy multi part range. for (Range r : ranges) { // Add multipart boundary and header fields for every range. sos.println(); sos.println("--" + MULTIPART_BOUNDARY); sos.println("Content-Type: " + mime_type); sos.println("Content-Range: bytes " + r.start + "-" + r.end + "/" + r.total); // Copy single part range of multi part range. copy(input, output, r.start, r.length); } // End with multipart boundary. sos.println(); sos.println("--" + MULTIPART_BOUNDARY + "--"); } } } finally { // Gently close streams. close(output); close(input); } } else { //java.io.OutputStream out = response.getOutputStream(); response.sendError(404); //out.write(uri.getBytes()); } } else { response.sendError(401); } } catch (Exception e) { System.out.println("Error en el processRequest() de ServidorArchivos: " + e.getMessage()); } } /** * Returns true if the given accept header accepts the given value. * @param acceptHeader The accept header. * @param toAccept The value to be accepted. * @return True if the given accept header accepts the given value. */ private static boolean accepts(String acceptHeader, String toAccept) { String[] acceptValues = acceptHeader.split("\\s*(,|;)\\s*"); Arrays.sort(acceptValues); return Arrays.binarySearch(acceptValues, toAccept) > -1 || Arrays.binarySearch(acceptValues, toAccept.replaceAll("/.*$", "/*")) > -1 || Arrays.binarySearch(acceptValues, "*/*") > -1; } /** * Returns true if the given match header matches the given value. * @param matchHeader The match header. * @param toMatch The value to be matched. * @return True if the given match header matches the given value. */ private static boolean matches(String matchHeader, String toMatch) { String[] matchValues = matchHeader.split("\\s*,\\s*"); Arrays.sort(matchValues); return Arrays.binarySearch(matchValues, toMatch) > -1 || Arrays.binarySearch(matchValues, "*") > -1; } /** * Returns a substring of the given string value from the given begin index to the given end * index as a long. If the substring is empty, then -1 will be returned * @param value The string value to return a substring as long for. * @param beginIndex The begin index of the substring to be returned as long. * @param endIndex The end index of the substring to be returned as long. * @return A substring of the given string value as long or -1 if substring is empty. */ private static long sublong(String value, int beginIndex, int endIndex) { String substring = value.substring(beginIndex, endIndex); return (substring.length() > 0) ? Long.parseLong(substring) : -1; } /** * Copy the given byte range of the given input to the given output. * @param input The input to copy the given range to the given output for. * @param output The output to copy the given range from the given input for. * @param start Start of the byte range. * @param length Length of the byte range. * @throws IOException If something fails at I/O level. */ private static void copy(RandomAccessFile input, OutputStream output, long start, long length) throws IOException { byte[] buffer = new byte[DEFAULT_BUFFER_SIZE]; int read; if (input.length() == length) { // Write full range. while ((read = input.read(buffer)) > 0) { output.write(buffer, 0, read); } } else { // Write partial range. input.seek(start); long toRead = length; while ((read = input.read(buffer)) > 0) { if ((toRead -= read) > 0) { output.write(buffer, 0, read); } else { output.write(buffer, 0, (int) toRead + read); break; } } } } /** * Close the given resource. * @param resource The resource to be closed. */ private static void close(Closeable resource) { if (resource != null) { try { resource.close(); } catch (IOException ignore) { // Ignore IOException. If you want to handle this anyway, it might be useful to know // that this will generally only be thrown when the client aborted the request. } } } // Inner classes ------------------------------------------------------------------------------ /** * This class represents a byte range. */ protected class Range { long start; long end; long length; long total; /** * Construct a byte range. * @param start Start of the byte range. * @param end End of the byte range. * @param total Total length of the byte source. */ public Range(long start, long end, long total) { this.start = start; this.end = end; this.length = end - start + 1; this.total = total; } } private List<String> getIdentifierRefs(Element organizatEl) { java.util.List<String> ident = new java.util.ArrayList<String>(); // TODO Auto-generated method stub java.util.List<Element> items = organizatEl.elements("item"); for (Element item : items) { String identi = item.attributeValue("identifierref"); ident.add(identi); java.util.List<String> subident = getIdentifierRefs(item); if (subident != null && subident.size() > 0) { ident.addAll(subident); } } return ident; } private Element selectItem(Element organizatEl, String sco) { java.util.List<Element> items = organizatEl.elements("item"); for (Element item : items) { if (item.attributeValue("identifier").equals(sco)) { return item; } Element retorno = selectItem(item, sco); if (retorno != null) { return retorno; } } return null; } private boolean isISO(String testString) { if (Validator.isNotNull(testString)) { return testString.substring(0, (testString.length() >= 1024 ? 1024 : testString.length())) .contains("ISO-8859-1"); } return false; } /** * Procesa el metodo HTTP GET. */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, java.io.IOException { processRequest(request, response, true); } /** * Procesa el metodo HTTP POST. */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, java.io.IOException { processRequest(request, response, true); } }