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 19package org.eclipse.jetty.continuation; 20 21import java.lang.reflect.Constructor; 22import javax.servlet.ServletRequest; 23import javax.servlet.ServletRequestWrapper; 24import javax.servlet.ServletResponse; 25 26/* ------------------------------------------------------------ */ 27/** ContinuationSupport. 28 * 29 * Factory class for accessing Continuation instances, which with either be 30 * native to the container (jetty >= 6), a servlet 3.0 or a faux continuation. 31 * 32 */ 33public class ContinuationSupport 34{ 35 static final boolean __jetty6; 36 static final boolean __servlet3; 37 static final Class<?> __waitingContinuation; 38 static final Constructor<? extends Continuation> __newServlet3Continuation; 39 static final Constructor<? extends Continuation> __newJetty6Continuation; 40 static 41 { 42 boolean servlet3Support=false; 43 Constructor<? extends Continuation>s3cc=null; 44 try 45 { 46 boolean servlet3=ServletRequest.class.getMethod("startAsync")!=null; 47 if (servlet3) 48 { 49 Class<? extends Continuation> s3c = ContinuationSupport.class.getClassLoader().loadClass("org.eclipse.jetty.continuation.Servlet3Continuation").asSubclass(Continuation.class); 50 s3cc=s3c.getConstructor(ServletRequest.class); 51 servlet3Support=true; 52 } 53 } 54 catch (Exception e) 55 {} 56 finally 57 { 58 __servlet3=servlet3Support; 59 __newServlet3Continuation=s3cc; 60 } 61 62 boolean jetty6Support=false; 63 Constructor<? extends Continuation>j6cc=null; 64 try 65 { 66 Class<?> jetty6ContinuationClass = ContinuationSupport.class.getClassLoader().loadClass("org.mortbay.util.ajax.Continuation"); 67 boolean jetty6=jetty6ContinuationClass!=null; 68 if (jetty6) 69 { 70 Class<? extends Continuation> j6c = ContinuationSupport.class.getClassLoader().loadClass("org.eclipse.jetty.continuation.Jetty6Continuation").asSubclass(Continuation.class); 71 j6cc=j6c.getConstructor(ServletRequest.class, jetty6ContinuationClass); 72 jetty6Support=true; 73 } 74 } 75 catch (Exception e) 76 {} 77 finally 78 { 79 __jetty6=jetty6Support; 80 __newJetty6Continuation=j6cc; 81 } 82 83 Class<?> waiting=null; 84 try 85 { 86 waiting=ContinuationSupport.class.getClassLoader().loadClass("org.mortbay.util.ajax.WaitingContinuation"); 87 } 88 catch (Exception e) 89 { 90 } 91 finally 92 { 93 __waitingContinuation=waiting; 94 } 95 } 96 97 /* ------------------------------------------------------------ */ 98 /** 99 * Get a Continuation. The type of the Continuation returned may 100 * vary depending on the container in which the application is 101 * deployed. It may be an implementation native to the container (eg 102 * org.eclipse.jetty.server.AsyncContinuation) or one of the utility 103 * implementations provided such as an internal <code>FauxContinuation</code> 104 * or a real implementation like {@link org.eclipse.jetty.continuation.Servlet3Continuation}. 105 * @param request The request 106 * @return a Continuation instance 107 */ 108 public static Continuation getContinuation(ServletRequest request) 109 { 110 Continuation continuation = (Continuation) request.getAttribute(Continuation.ATTRIBUTE); 111 if (continuation!=null) 112 return continuation; 113 114 while (request instanceof ServletRequestWrapper) 115 request=((ServletRequestWrapper)request).getRequest(); 116 117 if (__servlet3 ) 118 { 119 try 120 { 121 continuation=__newServlet3Continuation.newInstance(request); 122 request.setAttribute(Continuation.ATTRIBUTE,continuation); 123 return continuation; 124 } 125 catch(Exception e) 126 { 127 throw new RuntimeException(e); 128 } 129 } 130 131 if (__jetty6) 132 { 133 Object c=request.getAttribute("org.mortbay.jetty.ajax.Continuation"); 134 try 135 { 136 if (c==null || __waitingContinuation==null || __waitingContinuation.isInstance(c)) 137 continuation=new FauxContinuation(request); 138 else 139 continuation= __newJetty6Continuation.newInstance(request,c); 140 request.setAttribute(Continuation.ATTRIBUTE,continuation); 141 return continuation; 142 } 143 catch(Exception e) 144 { 145 throw new RuntimeException(e); 146 } 147 } 148 149 throw new IllegalStateException("!(Jetty || Servlet 3.0 || ContinuationFilter)"); 150 } 151 152 /* ------------------------------------------------------------ */ 153 /** 154 * @param request the servlet request 155 * @param response the servlet response 156 * @deprecated use {@link #getContinuation(ServletRequest)} 157 * @return the continuation 158 */ 159 @Deprecated 160 public static Continuation getContinuation(final ServletRequest request, final ServletResponse response) 161 { 162 return getContinuation(request); 163 } 164} 165