" + title + "

/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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. */ import java.io.IOException; import java.io.PrintWriter; import java.util.Enumeration; import java.util.Locale; import java.util.ResourceBundle; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.apache.tomcat.util.json.JSONFilter; import util.CookieFilter; import util.HTMLFilter; /** * Example servlet showing request headers * * @author James Duncan Davidson <duncan@eng.sun.com> */ public class RequestHeaderExample extends HttpServlet { private static final long serialVersionUID = 1L; @Override public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { if (prefersJSON(request.getHeader("Accept"))) { renderJSON(request, response); } else { renderHTML(request, response); } } /** * Returns true if the client appears to prefer a JSON response, * false otherwise. * * Note that this method is not very pedantic and uses only a very lazy * algorithm for checking whether JSON is "preferred". * * @param acceptHeader The value of the HTTP "Accept" header from the client. * * @return true if the client appears to prefer a JSON response, * false otherwise. */ protected boolean prefersJSON(String acceptHeader) { if (null == acceptHeader) { return false; } // mime/type, mime/type;q=n, ... // Don't bother with the q-factor. // This is not expected to be 100% accurate or spec-compliant String[] accepts = acceptHeader.split(","); for (String accept : accepts) { if (accept.contains("application/json")) { return true; } // text/html, application/html, etc. if (accept.contains("html")) { return false; } } return false; } protected void renderHTML(HttpServletRequest request, HttpServletResponse response) throws IOException { ResourceBundle rb = ResourceBundle.getBundle("LocalStrings",request.getLocale()); response.setContentType("text/html"); response.setCharacterEncoding("UTF-8"); PrintWriter out = response.getWriter(); out.println(""); out.println(""); out.println(""); String title = rb.getString("requestheader.title"); out.println("" + title + ""); out.println(""); out.println(""); // all links relative // XXX // making these absolute till we work out the // addition of a PathInfo issue out.println(""); out.println(" $\"view$ "); out.println(""); out.println(" $\"return\"$ "); out.println("

" + title + "

"); out.println(""); Enumeration e = request.getHeaderNames(); while (e.hasMoreElements()) { String headerName = e.nextElement(); String headerValue = request.getHeader(headerName); out.println(""); } out.println("

"); out.println(HTMLFilter.filter(headerName)); out.println("

"); if (headerName.toLowerCase(Locale.ENGLISH).contains("cookie")) { HttpSession session = request.getSession(false); String sessionId = null; if (session != null) { sessionId = session.getId(); } out.println(HTMLFilter.filter(CookieFilter.filter(headerValue, sessionId))); } else { out.println(HTMLFilter.filter(headerValue)); } out.println("

"); } protected void renderJSON(HttpServletRequest request, HttpServletResponse response) throws IOException { response.setContentType("application/json"); response.setCharacterEncoding("UTF-8"); PrintWriter out = response.getWriter(); out.append('['); Enumeration e = request.getHeaderNames(); while (e.hasMoreElements()) { String headerName = e.nextElement(); String headerValue = request.getHeader(headerName); out.append("{\"") .append(JSONFilter.escape(headerName)) .append("\":\"") .append(JSONFilter.escape(headerValue)) .append("\"}") ; if(e.hasMoreElements()) { out.append(','); } } out.print("]"); } @Override public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { doGet(request, response); } }