Source Code Cross Referenced for ClientPersistentFieldStorageImpl.java in  » Library » Tapestry » org » apache » tapestry » internal » services » Java Source Code / Java DocumentationJava Source Code and Java Documentation

Java Source Code / Java Documentation
1. 6.0 JDK Core
2. 6.0 JDK Modules
3. 6.0 JDK Modules com.sun
4. 6.0 JDK Modules com.sun.java
5. 6.0 JDK Modules sun
6. 6.0 JDK Platform
7. Ajax
8. Apache Harmony Java SE
9. Aspect oriented
10. Authentication Authorization
11. Blogger System
12. Build
13. Byte Code
14. Cache
15. Chart
16. Chat
17. Code Analyzer
18. Collaboration
19. Content Management System
20. Database Client
21. Database DBMS
22. Database JDBC Connection Pool
23. Database ORM
24. Development
25. EJB Server geronimo
26. EJB Server GlassFish
27. EJB Server JBoss 4.2.1
28. EJB Server resin 3.1.5
29. ERP CRM Financial
30. ESB
31. Forum
32. GIS
33. Graphic Library
34. Groupware
35. HTML Parser
36. IDE
37. IDE Eclipse
38. IDE Netbeans
39. Installer
40. Internationalization Localization
41. Inversion of Control
42. Issue Tracking
43. J2EE
44. JBoss
45. JMS
46. JMX
47. Library
48. Mail Clients
49. Net
50. Parser
51. PDF
52. Portal
53. Profiler
54. Project Management
55. Report
56. RSS RDF
57. Rule Engine
58. Science
59. Scripting
60. Search Engine
61. Security
62. Sevlet Container
63. Source Control
64. Swing Library
65. Template Engine
66. Test Coverage
67. Testing
68. UML
69. Web Crawler
70. Web Framework
71. Web Mail
72. Web Server
73. Web Services
74. Web Services apache cxf 2.0.1
75. Web Services AXIS2
76. Wiki Engine
77. Workflow Engines
78. XML
79. XML UI
Java
Java Tutorial
Java Open Source
Jar File Download
Java Articles
Java Products
Java by API
Photoshop Tutorials
Maya Tutorials
Flash Tutorials
3ds-Max Tutorials
Illustrator Tutorials
GIMP Tutorials
C# / C Sharp
C# / CSharp Tutorial
C# / CSharp Open Source
ASP.Net
ASP.NET Tutorial
JavaScript DHTML
JavaScript Tutorial
JavaScript Reference
HTML / CSS
HTML CSS Reference
C / ANSI-C
C Tutorial
C++
C++ Tutorial
Ruby
PHP
Python
Python Tutorial
Python Open Source
SQL Server / T-SQL
SQL Server / T-SQL Tutorial
Oracle PL / SQL
Oracle PL/SQL Tutorial
PostgreSQL
SQL / MySQL
MySQL Tutorial
VB.Net
VB.Net Tutorial
Flash / Flex / ActionScript
VBA / Excel / Access / Word
XML
XML Tutorial
Microsoft Office PowerPoint 2007 Tutorial
Microsoft Office Excel 2007 Tutorial
Microsoft Office Word 2007 Tutorial
Java Source Code / Java Documentation » Library » Tapestry » org.apache.tapestry.internal.services 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


001:        // Copyright 2007 The Apache Software Foundation
002:        //
003:        // Licensed under the Apache License, Version 2.0 (the "License");
004:        // you may not use this file except in compliance with the License.
005:        // You may obtain a copy of the License at
006:        //
007:        //     http://www.apache.org/licenses/LICENSE-2.0
008:        //
009:        // Unless required by applicable law or agreed to in writing, software
010:        // distributed under the License is distributed on an "AS IS" BASIS,
011:        // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012:        // See the License for the specific language governing permissions and
013:        // limitations under the License.
014:
015:        package org.apache.tapestry.internal.services;
016:
017:        import static org.apache.tapestry.ioc.IOCConstants.PERTHREAD_SCOPE;
018:        import static org.apache.tapestry.ioc.internal.util.CollectionFactory.newMap;
019:
020:        import java.io.ObjectInputStream;
021:        import java.io.Serializable;
022:        import java.util.Collection;
023:        import java.util.Collections;
024:        import java.util.Map;
025:
026:        import org.apache.tapestry.Link;
027:        import org.apache.tapestry.internal.TapestryInternalUtils;
028:        import org.apache.tapestry.internal.util.Base64ObjectInputStream;
029:        import org.apache.tapestry.internal.util.Base64ObjectOutputStream;
030:        import org.apache.tapestry.ioc.annotations.Scope;
031:        import org.apache.tapestry.ioc.internal.util.CollectionFactory;
032:        import org.apache.tapestry.services.PersistentFieldChange;
033:        import org.apache.tapestry.services.Request;
034:
035:        /**
036:         * Manages client-persistent values on behalf of a {@link ClientPersistentFieldStorageImpl}. Some
037:         * effort is made to ensure that we don't uncessarily convert between objects and Base64 (the
038:         * encoding used to record the value on the client).
039:         */
040:        @Scope(PERTHREAD_SCOPE)
041:        public class ClientPersistentFieldStorageImpl implements 
042:                ClientPersistentFieldStorage {
043:            static final String PARAMETER_NAME = "t:state:client";
044:
045:            private static class Key implements  Serializable {
046:                private static final long serialVersionUID = -2741540370081645945L;
047:
048:                private final String _pageName;
049:
050:                private final String _componentId;
051:
052:                private final String _fieldName;
053:
054:                Key(final String pageName, final String componentId,
055:                        final String fieldName) {
056:                    _pageName = pageName;
057:                    _componentId = componentId;
058:                    _fieldName = fieldName;
059:                }
060:
061:                public boolean matches(String pageName) {
062:                    return _pageName.equals(pageName);
063:                }
064:
065:                public PersistentFieldChange toChange(Object value) {
066:                    return new PersistentFieldChangeImpl(
067:                            _componentId == null ? "" : _componentId,
068:                            _fieldName, value);
069:                }
070:
071:                @Override
072:                public int hashCode() {
073:                    final int PRIME = 31;
074:
075:                    int result = 1;
076:
077:                    result = PRIME
078:                            * result
079:                            + ((_componentId == null) ? 0 : _componentId
080:                                    .hashCode());
081:
082:                    // _fieldName and _pageName are never null
083:
084:                    result = PRIME * result + _fieldName.hashCode();
085:                    result = PRIME * result + _pageName.hashCode();
086:
087:                    return result;
088:                }
089:
090:                @Override
091:                public boolean equals(Object obj) {
092:                    if (this  == obj)
093:                        return true;
094:                    if (obj == null)
095:                        return false;
096:                    if (getClass() != obj.getClass())
097:                        return false;
098:                    final Key other = (Key) obj;
099:
100:                    // _fieldName and _pageName are never null
101:
102:                    if (!_fieldName.equals(other._fieldName))
103:                        return false;
104:                    if (!_pageName.equals(other._pageName))
105:                        return false;
106:
107:                    if (_componentId == null) {
108:                        if (other._componentId != null)
109:                            return false;
110:                    } else if (!_componentId.equals(other._componentId))
111:                        return false;
112:
113:                    return true;
114:                }
115:            }
116:
117:            private final Map<Key, Object> _persistedValues = newMap();
118:
119:            private String _clientData;
120:
121:            private boolean _mapUptoDate = false;
122:
123:            public ClientPersistentFieldStorageImpl(Request request) {
124:                String value = request.getParameter(PARAMETER_NAME);
125:
126:                // MIME can encode to a '+' character; the browser converts that to a space; we convert it
127:                // back.
128:
129:                _clientData = value == null ? null : value.replace(' ', '+');
130:            }
131:
132:            public void updateLink(Link link) {
133:                refreshClientData();
134:
135:                if (_clientData != null)
136:                    link.addParameter(PARAMETER_NAME, _clientData);
137:            }
138:
139:            public Collection<PersistentFieldChange> gatherFieldChanges(
140:                    String pageName) {
141:                refreshMap();
142:
143:                if (_persistedValues.isEmpty())
144:                    return Collections.emptyList();
145:
146:                Collection<PersistentFieldChange> result = CollectionFactory
147:                        .newList();
148:
149:                for (Map.Entry<Key, Object> e : _persistedValues.entrySet()) {
150:                    Key key = e.getKey();
151:
152:                    if (key.matches(pageName))
153:                        result.add(key.toChange(e.getValue()));
154:                }
155:
156:                return result;
157:            }
158:
159:            public void postChange(String pageName, String componentId,
160:                    String fieldName, Object newValue) {
161:                refreshMap();
162:
163:                Key key = new Key(pageName, componentId, fieldName);
164:
165:                if (newValue == null)
166:                    _persistedValues.remove(key);
167:                else {
168:                    if (!Serializable.class.isInstance(newValue))
169:                        throw new IllegalArgumentException(ServicesMessages
170:                                .clientStateMustBeSerializable(newValue));
171:
172:                    _persistedValues.put(key, newValue);
173:                }
174:
175:                _clientData = null;
176:            }
177:
178:            @SuppressWarnings("unchecked")
179:            private void refreshMap() {
180:                if (_mapUptoDate)
181:                    return;
182:
183:                // Parse the client data to form the map.
184:
185:                restoreMapFromClientData();
186:
187:                _mapUptoDate = true;
188:            }
189:
190:            private void restoreMapFromClientData() {
191:                _persistedValues.clear();
192:
193:                if (_clientData == null)
194:                    return;
195:
196:                ObjectInputStream in = null;
197:
198:                try {
199:                    in = new Base64ObjectInputStream(_clientData);
200:
201:                    int count = in.readInt();
202:
203:                    for (int i = 0; i < count; i++) {
204:                        Key key = (Key) in.readObject();
205:                        Object value = in.readObject();
206:
207:                        _persistedValues.put(key, value);
208:                    }
209:                } catch (Exception ex) {
210:                    throw new RuntimeException(ServicesMessages
211:                            .corruptClientState(), ex);
212:                } finally {
213:                    TapestryInternalUtils.close(in);
214:                }
215:            }
216:
217:            private void refreshClientData() {
218:                // Client data will be null after a change to the map, or if there was no client data in the
219:                // request. In any other case where the client data is non-null, it is by definition
220:                // up-to date (since it is reset to null any time there's a change to the map).
221:
222:                if (_clientData != null)
223:                    return;
224:
225:                // Very typical: we're refreshing the client data but haven't created the map yet, and there
226:                // was no value in the request. Leave it as null.
227:
228:                if (!_mapUptoDate)
229:                    return;
230:
231:                // Null is also appropriate when the persisted values are empty.
232:
233:                if (_persistedValues.isEmpty())
234:                    return;
235:
236:                // Otherwise, time to update _clientData from _persistedValues
237:
238:                Base64ObjectOutputStream os = null;
239:
240:                try {
241:                    os = new Base64ObjectOutputStream();
242:
243:                    os.writeInt(_persistedValues.size());
244:
245:                    for (Map.Entry<Key, Object> e : _persistedValues.entrySet()) {
246:                        os.writeObject(e.getKey());
247:                        os.writeObject(e.getValue());
248:                    }
249:
250:                } catch (Exception ex) {
251:                    throw new RuntimeException(ex.getMessage(), ex);
252:                } finally {
253:                    TapestryInternalUtils.close(os);
254:                }
255:
256:                _clientData = os.toBase64();
257:            }
258:        }
www.java2java.com | Contact Us
Copyright 2009 - 12 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.