KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > apache > jetspeed > services > statemanager > StateManagerService


1 /*
2  * Copyright 2000-2002,2004 The Apache Software Foundation.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16
17 // package
18 package org.apache.jetspeed.services.statemanager;
19
20 // imports
21 import javax.servlet.http.HttpSession JavaDoc;
22
23 /**
24 * <p>The StateManagerService is a service that manages SessionState information.
25 * Each SessionState is identified by a unique key in this service. The SessionState
26 * is composed of name - value sets of attributes, stored under the key by the service.</p>
27 * <p>See the proposal: jakarta-jetspeed/proposals/StateManager.txt for more details.</p>
28 * <p>Attribute values placed into SessionStates may be automatically removed, for example when
29 * a SessionState expires in some way, or by means of some other automatic service. These value
30 * objects can be notified of their placement into and out of the SessionState. Objects that wish
31 * to receive this notification implement the SessionStateBindingListener interface. This is based
32 * on and similar to the HttpSessionBindingListener mechanism.</p>
33 * <p>To support the "current" routines; the ability to get a session state based
34 * on the current http session, this service must be installed properly into the
35 * procssing of each http request. At the start of the request, the HttpSession
36 * of the request must be passed into the setCurrentContext() method. At the end
37 * of the request, clearCurrentContext() is called. For Jetspeed, this is done in
38 * the JetspeedRunDataService, which is always going to be called by Turbine in this
39 * way.</p>
40 * @version $Revision: 1.5 $
41 * @see org.apache.jetspeed.services.statemanager.SessionState
42 * @see org.apache.jetspeed.services.statemanager.SessionStateBindingListener
43 * @author <a HREF="mailto:ggolden@apache.org">Glenn R. Golden</a>
44 */
45 public interface StateManagerService
46 {
47     /** The name used to find the service in the service manager. */
48     public String JavaDoc SERVICE_NAME = "StateManagerService";
49
50     /**
51     * Access the named attribute of the keyed state.
52     * @param key The state key.
53     * @param name The attribute name.
54     * @return The named attribute value of the keyed state.
55     */
56     public Object JavaDoc getAttribute ( String JavaDoc key, String JavaDoc name );
57
58     /**
59     * Set the named state attribute of the keyed state with the provided object.
60     * @param key The state key.
61     * @param name The attribute name.
62     * @param value The new value of the attribute (any object type).
63     */
64     public void setAttribute( String JavaDoc key, String JavaDoc name, Object JavaDoc value );
65
66     /**
67     * Remove the named state attribute of the keyed state, if it exists.
68     * @param key The state key.
69     * @param name The attribute name.
70     */
71     public void removeAttribute( String JavaDoc key, String JavaDoc name );
72
73     /**
74     * Remove all state attribute of the keyed state.
75     * @param key The state key.
76     */
77     public void clear( String JavaDoc key );
78
79     /**
80     * Access an array of all names of attributes stored in the keyed state.
81     * @param key The state key.
82     * @return An array of all names of attributes stored in the keyed state.
83     */
84     public String JavaDoc[] getAttributeNames( String JavaDoc key );
85
86     /**
87     * Access an SessionState object with the given key.
88     * @param key The SessionState key.
89     * @return an SessionState object with the given key.
90     */
91     public SessionState getSessionState( String JavaDoc key );
92
93     /**
94     * Access the SessionState object associated with the current request's http session.
95     * The session id is used as the key.
96     * @return an SessionState object associated with the current request's http session.
97     */
98     public SessionState getCurrentSessionState();
99
100     /**
101     * Access the SessionState object associated with the current request's http session with the given key.
102     * @param key The string to add to the session id to form the SessionState key.
103     * @return an SessionState object associated with the current request's http session with the given key.
104     */
105     public SessionState getCurrentSessionState( String JavaDoc key );
106
107     /**
108     * Retire, forget about and clean up all states that start with the given key.
109     * @param keyStart The beginning of the key of the states to clean up.
110     */
111     public void retireState( String JavaDoc keyStart );
112
113     /**
114     * Set the "current" context for this thread -
115     * Call this at the start of each request, and call %%% at the end.
116     * getCurrentSession() uses this for the session state key.
117     * @param session the HttpSession of the current request.
118     */
119     public void setCurrentContext( HttpSession JavaDoc session );
120
121     /**
122     * Clear the "current context for this thread -
123     * Call at the end of each request, balanced with calls to setCurrentContext()
124     */
125     public void clearCurrentContext();
126
127 } // interface StateManagerService
128
129 /**********************************************************************************
130 *
131 * $Header: /home/cvs/jakarta-jetspeed/src/java/org/apache/jetspeed/services/statemanager/StateManagerService.java,v 1.5 2004/02/23 03:38:28 jford Exp $
132 *
133 **********************************************************************************/
134
135
Popular Tags