Java tutorial
/* * Copyright 2005 Red Hat, Inc. and/or its affiliates. * * 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.guvnor.common.services.backend.file.upload; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.net.URISyntaxException; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Iterator; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileItemFactory; import org.apache.commons.fileupload.disk.DiskFileItemFactory; import org.apache.commons.fileupload.servlet.ServletFileUpload; import org.apache.commons.io.IOUtils; import org.guvnor.common.services.shared.file.upload.FileManagerFields; import org.guvnor.common.services.shared.file.upload.FileOperation; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.uberfire.backend.server.util.Paths; import org.uberfire.backend.vfs.Path; import org.uberfire.server.BaseFilteredServlet; /** * This is for dealing with assets that have an attachment (ie assets that are really an attachment). */ //TODO: Basic authentication public abstract class AbstractFileServlet extends BaseFilteredServlet { private static final Logger log = LoggerFactory.getLogger(AbstractFileServlet.class); private static final SimpleDateFormat sdf = new SimpleDateFormat("dd-MMM-yyyy HH:mm:ss"); private static final long serialVersionUID = 510l; /** * Load resource * @param path * @param request * @return */ protected abstract InputStream doLoad(final Path path, final HttpServletRequest request); /** * Create a new resource * @param path * @param data * @param request * @param comment */ protected abstract void doCreate(final Path path, final InputStream data, final HttpServletRequest request, final String comment); /** * Update a resource * @param path * @param data * @param request * @param comment */ protected abstract void doUpdate(final Path path, final InputStream data, final HttpServletRequest request, final String comment); /** * Convert fileName and contextPath into a Path * @param fileName * @param contextPath * @return */ protected abstract Path convertPath(final String fileName, final String contextPath) throws URISyntaxException; /** * Convert fullPath into a Path * @param fullPath * @return */ protected abstract Path convertPath(final String fullPath) throws URISyntaxException; /** * Posting accepts content of various types. */ protected void doPost(final HttpServletRequest request, final HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); final FormData item = getFormData(request); if (item.getFile() != null) { response.getWriter().write(processUpload(item, request, response)); return; } response.getWriter().write("NO-SCRIPT-DATA"); } /** * Get the form data from the inbound request. */ @SuppressWarnings("rawtypes") private FormData getFormData(final HttpServletRequest request) throws IOException { final FileItemFactory factory = new DiskFileItemFactory(); final ServletFileUpload upload = new ServletFileUpload(factory); upload.setHeaderEncoding("UTF-8"); //See https://code.google.com/p/google-web-toolkit/issues/detail?id=4682 request.setCharacterEncoding("UTF-8"); final FormData data = new FormData(); try { final List items = upload.parseRequest(request); final Iterator it = items.iterator(); FileOperation operation = null; String fileName = null; String contextPath = null; String fullPath = null; while (it.hasNext()) { final FileItem item = (FileItem) it.next(); if (!item.isFormField()) { data.setFile(item); } else if (item.getFieldName().equals(FileManagerFields.FORM_FIELD_PATH)) { contextPath = item.getString("UTF-8"); log.debug("path:" + contextPath); } else if (item.getFieldName().equals(FileManagerFields.FORM_FIELD_NAME)) { fileName = item.getString("UTF-8"); log.debug("name:" + fileName); } else if (item.getFieldName().equals(FileManagerFields.FORM_FIELD_FULL_PATH)) { fullPath = item.getString("UTF-8"); log.debug("full path:" + fullPath); } else if (item.getFieldName().equals(FileManagerFields.FORM_FIELD_OPERATION)) { operation = FileOperation.valueOf(item.getString("UTF-8")); log.debug("operation:" + operation); } } if (operation == null) { throw new IllegalArgumentException("FORM_FIELD_OPERATION is null. Cannot process upload."); } org.uberfire.java.nio.file.Path path; switch (operation) { case CREATE: if (fileName == null) { throw new IllegalArgumentException("FORM_FIELD_NAME is null. Cannot process upload."); } if (contextPath == null) { throw new IllegalArgumentException("FORM_FIELD_PATH is null. Cannot process upload."); } data.setOperation(operation); data.setTargetPath(convertPath(fileName, contextPath)); break; case UPDATE: if (fullPath == null) { throw new IllegalArgumentException("FORM_FIELD_FULL_PATH is null. Cannot process upload."); } data.setOperation(operation); data.setTargetPath(convertPath(fullPath)); } return data; } catch (Exception e) { throw new org.uberfire.java.nio.IOException(e.getMessage()); } } private String processUpload(final FormData item, final HttpServletRequest request, final HttpServletResponse response) throws IOException { // If the file it doesn't exist. if ("".equals(item.getFile().getName())) { throw new IOException("No file selected."); } final String processResult = uploadFile(item, request, response); return processResult; } private String uploadFile(final FormData item, final HttpServletRequest request, final HttpServletResponse response) throws IOException { final InputStream fileData = item.getFile().getInputStream(); final org.uberfire.backend.vfs.Path targetPath = item.getTargetPath(); if (!validateAccess(Paths.convert(targetPath), response)) { return "FAIL"; } try { switch (item.getOperation()) { case CREATE: doCreate(targetPath, fileData, request, "Uploaded " + getTimestamp()); break; case UPDATE: doUpdate(targetPath, fileData, request, "Uploaded " + getTimestamp()); } } finally { item.getFile().getInputStream().close(); } return "OK"; } private String getTimestamp() { final Calendar now = Calendar.getInstance(); final StringBuilder sb = new StringBuilder(); sb.append(sdf.format(now.getTime())); return sb.toString(); } /** * doGet acting like a dispatcher. */ protected void doGet(final HttpServletRequest request, final HttpServletResponse response) throws ServletException, IOException { final String path = request.getParameter(FileManagerFields.FORM_FIELD_PATH); if (path != null) { processAttachmentDownload(path, request, response); } else { response.sendError(HttpServletResponse.SC_BAD_REQUEST); } } protected void processAttachmentDownload(final String url, final HttpServletRequest request, final HttpServletResponse response) throws IOException { final ByteArrayOutputStream output = new ByteArrayOutputStream(); try { final Path sourcePath = convertPath(url); if (!validateAccess(Paths.convert(sourcePath), response)) { return; } IOUtils.copy(doLoad(sourcePath, request), output); //Use the encoded form from in the URL (rather than encode/decode for fun!) //See http://tools.ietf.org/html/rfc6266 for details of filename* content-disposition usage final String fileName = url.substring(url.lastIndexOf("/") + 1); response.setContentType("application/x-download"); response.setHeader("Content-Disposition", "attachment; filename*=utf-8''" + fileName); response.setContentLength(output.size()); response.getOutputStream().write(output.toByteArray()); response.getOutputStream().flush(); } catch (Exception e) { throw new org.uberfire.java.nio.IOException(e.getMessage()); } } }