Jake Slack | 03928ae | 2014-05-13 18:41:56 -0700 | [diff] [blame] | 1 | // |
| 2 | // ======================================================================== |
| 3 | // Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd. |
| 4 | // ------------------------------------------------------------------------ |
| 5 | // All rights reserved. This program and the accompanying materials |
| 6 | // are made available under the terms of the Eclipse Public License v1.0 |
| 7 | // and Apache License v2.0 which accompanies this distribution. |
| 8 | // |
| 9 | // The Eclipse Public License is available at |
| 10 | // http://www.eclipse.org/legal/epl-v10.html |
| 11 | // |
| 12 | // The Apache License v2.0 is available at |
| 13 | // http://www.opensource.org/licenses/apache2.0.php |
| 14 | // |
| 15 | // You may elect to redistribute this code under either of these licenses. |
| 16 | // ======================================================================== |
| 17 | // |
| 18 | |
| 19 | package org.eclipse.jetty.servlets; |
| 20 | |
| 21 | import java.io.IOException; |
| 22 | |
| 23 | import javax.servlet.RequestDispatcher; |
| 24 | import javax.servlet.ServletContext; |
| 25 | import javax.servlet.ServletException; |
| 26 | import javax.servlet.http.HttpServlet; |
| 27 | import javax.servlet.http.HttpServletRequest; |
| 28 | import javax.servlet.http.HttpServletResponse; |
| 29 | |
| 30 | /* ------------------------------------------------------------ */ |
| 31 | /** Concatenation Servlet |
| 32 | * This servlet may be used to concatenate multiple resources into |
| 33 | * a single response. It is intended to be used to load multiple |
| 34 | * javascript or css files, but may be used for any content of the |
| 35 | * same mime type that can be meaningfully concatenated. |
| 36 | * <p> |
| 37 | * The servlet uses {@link RequestDispatcher#include(javax.servlet.ServletRequest, javax.servlet.ServletResponse)} |
| 38 | * to combine the requested content, so dynamically generated content |
| 39 | * may be combined (Eg engine.js for DWR). |
| 40 | * <p> |
| 41 | * The servlet uses parameter names of the query string as resource names |
| 42 | * relative to the context root. So these script tags: |
| 43 | * <pre> |
| 44 | * <script type="text/javascript" src="../js/behaviour.js"></script> |
| 45 | * <script type="text/javascript" src="../js/ajax.js&/chat/chat.js"></script> |
| 46 | * <script type="text/javascript" src="../chat/chat.js"></script> |
| 47 | * </pre> can be replaced with the single tag (with the ConcatServlet mapped to /concat): |
| 48 | * <pre> |
| 49 | * <script type="text/javascript" src="../concat?/js/behaviour.js&/js/ajax.js&/chat/chat.js"></script> |
| 50 | * </pre> |
| 51 | * The {@link ServletContext#getMimeType(String)} method is used to determine the |
| 52 | * mime type of each resource. If the types of all resources do not match, then a 415 |
| 53 | * UNSUPPORTED_MEDIA_TYPE error is returned. |
| 54 | * <p> |
| 55 | * If the init parameter "development" is set to "true" then the servlet will run in |
| 56 | * development mode and the content will be concatenated on every request. Otherwise |
| 57 | * the init time of the servlet is used as the lastModifiedTime of the combined content |
| 58 | * and If-Modified-Since requests are handled with 206 NOT Modified responses if |
| 59 | * appropriate. This means that when not in development mode, the servlet must be |
| 60 | * restarted before changed content will be served. |
| 61 | * |
| 62 | * |
| 63 | * |
| 64 | */ |
| 65 | public class ConcatServlet extends HttpServlet |
| 66 | { |
| 67 | boolean _development; |
| 68 | long _lastModified; |
| 69 | ServletContext _context; |
| 70 | |
| 71 | /* ------------------------------------------------------------ */ |
| 72 | public void init() throws ServletException |
| 73 | { |
| 74 | _lastModified=System.currentTimeMillis(); |
| 75 | _context=getServletContext(); |
| 76 | _development="true".equals(getInitParameter("development")); |
| 77 | } |
| 78 | |
| 79 | /* ------------------------------------------------------------ */ |
| 80 | /* |
| 81 | * @return The start time of the servlet unless in development mode, in which case -1 is returned. |
| 82 | */ |
| 83 | protected long getLastModified(HttpServletRequest req) |
| 84 | { |
| 85 | return _development?-1:_lastModified; |
| 86 | } |
| 87 | |
| 88 | /* ------------------------------------------------------------ */ |
| 89 | protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException |
| 90 | { |
| 91 | String q=req.getQueryString(); |
| 92 | if (q==null) |
| 93 | { |
| 94 | resp.sendError(HttpServletResponse.SC_NO_CONTENT); |
| 95 | return; |
| 96 | } |
| 97 | |
| 98 | String[] parts = q.split("\\&"); |
| 99 | String type=null; |
| 100 | for (int i=0;i<parts.length;i++) |
| 101 | { |
| 102 | String t = _context.getMimeType(parts[i]); |
| 103 | if (t!=null) |
| 104 | { |
| 105 | if (type==null) |
| 106 | type=t; |
| 107 | else if (!type.equals(t)) |
| 108 | { |
| 109 | resp.sendError(HttpServletResponse.SC_UNSUPPORTED_MEDIA_TYPE); |
| 110 | return; |
| 111 | } |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | if (type!=null) |
| 116 | resp.setContentType(type); |
| 117 | |
| 118 | for (int i=0;i<parts.length;i++) |
| 119 | { |
| 120 | RequestDispatcher dispatcher=_context.getRequestDispatcher(parts[i]); |
| 121 | if (dispatcher!=null) |
| 122 | dispatcher.include(req,resp); |
| 123 | } |
| 124 | } |
| 125 | } |