1
2
3 /*
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
5 *
6 * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
7 *
8 * Portions Copyright Apache Software Foundation.
9 *
10 * The contents of this file are subject to the terms of either the GNU
11 * General Public License Version 2 only ("GPL") or the Common Development
12 * and Distribution License("CDDL") (collectively, the "License"). You
13 * may not use this file except in compliance with the License. You can obtain
14 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
15 * or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
16 * language governing permissions and limitations under the License.
17 *
18 * When distributing the software, include this License Header Notice in each
19 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
20 * Sun designates this particular file as subject to the "Classpath" exception
21 * as provided by Sun in the GPL Version 2 section of the License file that
22 * accompanied this code. If applicable, add the following below the License
23 * Header, with the fields enclosed by brackets [] replaced by your own
24 * identifying information: "Portions Copyrighted [year]
25 * [name of copyright owner]"
26 *
27 * Contributor(s):
28 *
29 * If you wish your version of this file to be governed by only the CDDL or
30 * only the GPL Version 2, indicate your decision by adding "[Contributor]
31 * elects to include this software in this distribution under the [CDDL or GPL
32 * Version 2] license." If you don't indicate a single choice of license, a
33 * recipient has the option to distribute your version of this file under
34 * either the CDDL, the GPL Version 2 or to extend the choice of license to
35 * its licensees as provided above. However, if you add GPL Version 2 code
36 * and therefore, elected the GPL Version 2 license, then the option applies
37 * only if the new code is made subject to such option by the copyright
38 * holder.
39 */
40 package org.apache.tomcat.util.handler;
41
42 import java.io;
43 import java.util;
44 import java.security;
45
46
47 /**
48 * The lowest level component of Jk ( and hopefully Coyote ).
49 *
50 * Try to keep it minimal and flexible - add only if you _have_ to add.
51 *
52 * It is similar in concept and can implement/wrap tomcat3.3 Interceptor, tomcat4.0 Valve,
53 * axis Handler, tomcat3.3 Handler, apache2 Hooks etc.
54 *
55 * Both iterative (Interceptor, Hook ) and recursive ( Valve ) behavior are supported.
56 * Named TcHandler because Handler name is too overloaded.
57 *
58 * The interface allows both stateless and statefull implementations ( like Servlet ).
59 *
60 * @author Costin Manolache
61 */
62 public abstract class TcHandler {
63 public static final int OK=0;
64 public static final int LAST=1;
65 public static final int ERROR=2;
66
67 protected Hashtable attributes=new Hashtable();
68 protected TcHandler next;
69 protected String name;
70 protected int id;
71
72 // -------------------- Configuration --------------------
73
74 /** Set the name of the handler. Will allways be called by
75 * worker env after creating the worker.
76 */
77 public void setName(String s ) {
78 name=s;
79 }
80
81 public String getName() {
82 return name;
83 }
84
85 /** Set the id of the worker. It can be used for faster dispatch.
86 * Must be unique, managed by whoever creates the handlers.
87 */
88 public void setId( int id ) {
89 this.id=id;
90 }
91
92 public int getId() {
93 return id;
94 }
95
96 /** Catalina-style "recursive" invocation. A handler is required to call
97 * the next handler if set.
98 */
99 public void setNext( TcHandler h ) {
100 next=h;
101 }
102
103
104 /** Base implementation will just save all attributes.
105 * It is higly desirable to override this and allow runtime reconfiguration.
106 * XXX Should I make it abstract and force everyone to override ?
107 */
108 public void setAttribute( String name, Object value ) {
109 attributes.put( name, value );
110 }
111
112 /** Get an attribute. Override to allow runtime query ( attribute can be
113 * anything, including statistics, etc )
114 */
115 public Object getAttribute( String name ) {
116 return attributes.get(name) ;
117 }
118
119 //-------------------- Lifecycle --------------------
120
121 /** Should register the request types it can handle,
122 * same style as apache2.
123 */
124 public void init() throws IOException {
125 }
126
127 /** Clean up and stop the handler. Override if needed.
128 */
129 public void destroy() throws IOException {
130 }
131
132 public void start() throws IOException {
133 }
134
135 public void stop() throws IOException {
136 }
137
138 // -------------------- Action --------------------
139
140 /** The 'hook' method. If a 'next' was set, invoke should call it ( recursive behavior,
141 * similar with valve ).
142 *
143 * The application using the handler can also iterate, using the same semantics with
144 * Interceptor or APR hooks.
145 *
146 * @returns OK, LAST, ERROR Status of the execution, semantic similar with apache
147 */
148 public abstract int invoke(TcHandlerCtx tcCtx) throws IOException;
149
150
151
152 }