Java tutorial
/* * Copyright 2000-2018 Vaadin Ltd. * * 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 com.vaadin.server; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.net.MalformedURLException; import java.net.URL; import java.util.List; import java.util.logging.Level; import java.util.logging.Logger; import javax.servlet.http.HttpServletRequest; import com.vaadin.server.communication.PushRequestHandler; import com.vaadin.server.communication.ServletBootstrapHandler; import com.vaadin.server.communication.ServletUIInitHandler; import com.vaadin.ui.UI; public class VaadinServletService extends VaadinService { /** * Should never be used directly, always use {@link #getServlet()} */ private final VaadinServlet servlet; public VaadinServletService(VaadinServlet servlet, DeploymentConfiguration deploymentConfiguration) throws ServiceException { super(deploymentConfiguration); this.servlet = servlet; } /** * Creates a servlet service. This method is for use by dependency injection * frameworks etc. {@link #getServlet()} should be overridden (or otherwise * intercepted) so it does not return <code>null</code>. * * @since 8.2 */ protected VaadinServletService() { this.servlet = null; } @Override protected List<RequestHandler> createRequestHandlers() throws ServiceException { List<RequestHandler> handlers = super.createRequestHandlers(); handlers.add(0, new ServletBootstrapHandler()); handlers.add(new ServletUIInitHandler()); if (isAtmosphereAvailable()) { try { handlers.add(new PushRequestHandler(this)); } catch (ServiceException e) { // Atmosphere init failed. Push won't work but we don't throw a // service exception as we don't want to prevent non-push // applications from working getLogger().log(Level.WARNING, "Error initializing Atmosphere. Push will not work.", e); } } return handlers; } /** * Retrieves a reference to the servlet associated with this service. Should * be overridden (or otherwise intercepted) if the no-arg constructor is * used to prevent NPEs. * * @return A reference to the VaadinServlet this service is using */ public VaadinServlet getServlet() { return servlet; } @Override public String getStaticFileLocation(VaadinRequest request) { VaadinServletRequest servletRequest = (VaadinServletRequest) request; String staticFileLocation; // if property is defined in configurations, use that staticFileLocation = getDeploymentConfiguration().getResourcesPath(); if (staticFileLocation != null) { return staticFileLocation; } // the last (but most common) option is to generate default location // from request by finding how many "../" should be added to the // requested path before we get to the context root String requestedPath = servletRequest.getServletPath(); String pathInfo = servletRequest.getPathInfo(); if (pathInfo != null) { requestedPath += pathInfo; } return getCancelingRelativePath(requestedPath); } /** * Gets a relative path that cancels the provided path. This essentially * adds one .. for each part of the path to cancel. * * @param pathToCancel * the path that should be canceled * @return a relative path that cancels out the provided path segment */ public static String getCancelingRelativePath(String pathToCancel) { StringBuilder sb = new StringBuilder("."); // Start from i = 1 to ignore first slash for (int i = 1; i < pathToCancel.length(); i++) { if (pathToCancel.charAt(i) == '/') { sb.append("/.."); } } return sb.toString(); } /** * Gets a relative path you can use to refer to the context root. * * @param request * the request for which the location should be determined * @return A relative path to the context root. Never ends with a slash (/). * * @since 8.0.3 */ public static String getContextRootRelativePath(VaadinRequest request) { VaadinServletRequest servletRequest = (VaadinServletRequest) request; // Generate location from the request by finding how many "../" should // be added to the servlet path before we get to the context root String servletPath = servletRequest.getServletPath(); if (servletPath == null) { // Not allowed by the spec but servers are servers... servletPath = ""; } String pathInfo = servletRequest.getPathInfo(); if (pathInfo != null && !pathInfo.isEmpty()) { servletPath += pathInfo; } return getCancelingRelativePath(servletPath); } @Override public String getConfiguredWidgetset(VaadinRequest request) { return getDeploymentConfiguration().getWidgetset(VaadinServlet.DEFAULT_WIDGETSET); } @Override public String getConfiguredTheme(VaadinRequest request) { // Use the default return VaadinServlet.getDefaultTheme(); } @Override public boolean isStandalone(VaadinRequest request) { return true; } @Override public String getMimeType(String resourceName) { return getServlet().getServletContext().getMimeType(resourceName); } @Override public File getBaseDirectory() { final String realPath = VaadinServlet.getResourcePath(getServlet().getServletContext(), "/"); if (realPath == null) { return null; } return new File(realPath); } @Override protected boolean requestCanCreateSession(VaadinRequest request) { if (ServletUIInitHandler.isUIInitRequest(request)) { // This is the first request if you are embedding by writing the // embedding code yourself return true; } else if (isOtherRequest(request)) { /* * I.e URIs that are not RPC calls or static (theme) files. */ return true; } return false; } private boolean isOtherRequest(VaadinRequest request) { // TODO This should be refactored in some way. It should not be // necessary to check all these types. return (!ServletPortletHelper.isAppRequest(request) && !ServletUIInitHandler.isUIInitRequest(request) && !ServletPortletHelper.isFileUploadRequest(request) && !ServletPortletHelper.isHeartbeatRequest(request) && !ServletPortletHelper.isPublishedFileRequest(request) && !ServletPortletHelper.isUIDLRequest(request) && !ServletPortletHelper.isPushRequest(request)); } @Override protected URL getApplicationUrl(VaadinRequest request) throws MalformedURLException { return getServlet().getApplicationUrl((VaadinServletRequest) request); } public static HttpServletRequest getCurrentServletRequest() { return VaadinServletRequest.getCurrent(); } public static VaadinServletResponse getCurrentResponse() { return VaadinServletResponse.getCurrent(); } @Override public String getServiceName() { return getServlet().getServletName(); } @Override public InputStream getThemeResourceAsStream(UI uI, String themeName, String resource) throws IOException { String filename = "/" + VaadinServlet.THEME_DIR_PATH + '/' + themeName + "/" + resource; URL resourceUrl = getServlet().findResourceURL(filename); if (resourceUrl != null) { // security check: do not permit navigation out of the VAADIN // directory if (!getServlet().isAllowedVAADINResourceUrl(null, resourceUrl)) { throw new IOException(String.format( "Requested resource [{0}] not accessible in the VAADIN directory or access to it is forbidden.", filename)); } return resourceUrl.openStream(); } else { return null; } } @Override public String getMainDivId(VaadinSession session, VaadinRequest request, Class<? extends UI> uiClass) { String appId = null; try { URL appUrl = getServlet().getApplicationUrl((VaadinServletRequest) request); appId = appUrl.getPath(); } catch (MalformedURLException e) { // Just ignore problem here } if (appId == null || appId.isEmpty() || "/".equals(appId)) { appId = "ROOT"; } appId = appId.replaceAll("[^a-zA-Z0-9]", ""); // Add hashCode to the end, so that it is still (sort of) // predictable, but indicates that it should not be used in CSS // and // such: int hashCode = appId.hashCode(); if (hashCode < 0) { hashCode = -hashCode; } appId = appId + "-" + hashCode; return appId; } private static final Logger getLogger() { return Logger.getLogger(VaadinServletService.class.getName()); } }