Source Code Cross Referenced for TransitionExecutingStateExceptionHandler.java in  » Workflow-Engines » spring-webflow-1.0.4 » org » springframework » webflow » engine » support » 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 » Workflow Engines » spring webflow 1.0.4 » org.springframework.webflow.engine.support 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


001:        /*
002:         * Copyright 2004-2007 the original author or authors.
003:         *
004:         * Licensed under the Apache License, Version 2.0 (the "License");
005:         * you may not use this file except in compliance with the License.
006:         * You may obtain a copy of the License at
007:         *
008:         *      http://www.apache.org/licenses/LICENSE-2.0
009:         *
010:         * Unless required by applicable law or agreed to in writing, software
011:         * distributed under the License is distributed on an "AS IS" BASIS,
012:         * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013:         * See the License for the specific language governing permissions and
014:         * limitations under the License.
015:         */
016:        package org.springframework.webflow.engine.support;
017:
018:        import java.util.HashMap;
019:        import java.util.Map;
020:
021:        import org.apache.commons.logging.Log;
022:        import org.apache.commons.logging.LogFactory;
023:        import org.springframework.core.JdkVersion;
024:        import org.springframework.core.NestedRuntimeException;
025:        import org.springframework.core.style.ToStringCreator;
026:        import org.springframework.util.Assert;
027:        import org.springframework.webflow.engine.ActionList;
028:        import org.springframework.webflow.engine.FlowExecutionExceptionHandler;
029:        import org.springframework.webflow.engine.RequestControlContext;
030:        import org.springframework.webflow.engine.TargetStateResolver;
031:        import org.springframework.webflow.engine.Transition;
032:        import org.springframework.webflow.execution.FlowExecutionException;
033:        import org.springframework.webflow.execution.RequestContext;
034:        import org.springframework.webflow.execution.ViewSelection;
035:
036:        /**
037:         * A flow execution exception handler that maps the occurence of a specific type of
038:         * exception to a transition to a new {@link org.springframework.webflow.engine.State}.
039:         * <p>
040:         * The handled {@link FlowExecutionException} will be exposed in flash scope as
041:         * {@link #STATE_EXCEPTION_ATTRIBUTE}. The underlying root cause of that exception
042:         * will be exposed in flash scope as {@link #ROOT_CAUSE_EXCEPTION_ATTRIBUTE}.
043:         * 
044:         * @author Keith Donald
045:         */
046:        public class TransitionExecutingStateExceptionHandler implements 
047:                FlowExecutionExceptionHandler {
048:
049:            // this class should really have been called TransitionExecutingFlowExceptionHandler
050:
051:            private static final Log logger = LogFactory
052:                    .getLog(TransitionExecutingStateExceptionHandler.class);
053:
054:            /**
055:             * The name of the attribute to expose a handled exception under in
056:             * flash scope ("stateException").
057:             */
058:            public static final String STATE_EXCEPTION_ATTRIBUTE = "stateException";
059:
060:            /**
061:             * The name of the attribute to expose a root cause of a handled exception
062:             * under in flash scope ("rootCauseException").
063:             */
064:            public static final String ROOT_CAUSE_EXCEPTION_ATTRIBUTE = "rootCauseException";
065:
066:            /**
067:             * The exceptionType->targetStateResolver map.
068:             */
069:            private Map exceptionTargetStateMappings = new HashMap();
070:
071:            /**
072:             * The list of actions to execute when this handler handles an exception.
073:             */
074:            private ActionList actionList = new ActionList();
075:
076:            /**
077:             * Adds an exception->state mapping to this handler.
078:             * @param exceptionClass the type of exception to map
079:             * @param targetStateId the id of the state to transition to if the
080:             * specified type of exception is handled
081:             * @return this handler, to allow for adding multiple mappings in a single
082:             * statement
083:             */
084:            public TransitionExecutingStateExceptionHandler add(
085:                    Class exceptionClass, String targetStateId) {
086:                return add(exceptionClass, new DefaultTargetStateResolver(
087:                        targetStateId));
088:            }
089:
090:            /**
091:             * Adds a exception->state mapping to this handler.
092:             * @param exceptionClass the type of exception to map
093:             * @param targetStateResolver the resolver to calculate the state to
094:             * transition to if the specified type of exception is handled
095:             * @return this handler, to allow for adding multiple mappings in a single
096:             * statement
097:             */
098:            public TransitionExecutingStateExceptionHandler add(
099:                    Class exceptionClass,
100:                    TargetStateResolver targetStateResolver) {
101:                Assert.notNull(exceptionClass,
102:                        "The exception class is required");
103:                Assert.notNull(targetStateResolver,
104:                        "The target state resolver is required");
105:                exceptionTargetStateMappings.put(exceptionClass,
106:                        targetStateResolver);
107:                return this ;
108:            }
109:
110:            /**
111:             * Returns the list of actions to execute when this handler handles an exception.
112:             * The returned list is mutable.
113:             */
114:            public ActionList getActionList() {
115:                return actionList;
116:            }
117:
118:            public boolean handles(FlowExecutionException e) {
119:                return getTargetStateResolver(e) != null;
120:            }
121:
122:            public ViewSelection handle(FlowExecutionException exception,
123:                    RequestControlContext context) {
124:                if (logger.isDebugEnabled()) {
125:                    logger.debug("Handling state exception " + exception,
126:                            exception);
127:                }
128:                exposeException(context, exception, findRootCause(exception));
129:                actionList.execute(context);
130:                return context.execute(new Transition(
131:                        getTargetStateResolver(exception)));
132:            }
133:
134:            // helpers
135:
136:            /**
137:             * Exposes the given flow exception and root cause in flash scope to make
138:             * them available for response rendering. Subclasses can override this
139:             * if they want to expose the exceptions in a different way or do special
140:             * processing before the exceptions are exposed.
141:             * @param context the request control context
142:             * @param exception the exception being handled
143:             * @param rootCause root cause of the exception being handled (could be null)
144:             * @since 1.0.2
145:             */
146:            protected void exposeException(RequestContext context,
147:                    FlowExecutionException exception, Throwable rootCause) {
148:                // note that all Throwables are Serializable so putting them in flash
149:                // scope should not be a problem
150:                context.getFlashScope().put(STATE_EXCEPTION_ATTRIBUTE,
151:                        exception);
152:                if (logger.isDebugEnabled()) {
153:                    logger.debug("Exposing state exception root cause "
154:                            + rootCause + " under attribute '"
155:                            + ROOT_CAUSE_EXCEPTION_ATTRIBUTE + "'");
156:                }
157:                context.getFlashScope().put(ROOT_CAUSE_EXCEPTION_ATTRIBUTE,
158:                        rootCause);
159:            }
160:
161:            /**
162:             * Find the mapped target state resolver for given exception. Returns
163:             * <code>null</code> if no mapping can be found for given exception. Will
164:             * try all exceptions in the exception cause chain.
165:             */
166:            protected TargetStateResolver getTargetStateResolver(
167:                    FlowExecutionException e) {
168:                if (JdkVersion.getMajorJavaVersion() == JdkVersion.JAVA_13) {
169:                    return getTargetStateResolver13(e);
170:                } else {
171:                    return getTargetStateResolver14(e);
172:                }
173:            }
174:
175:            /**
176:             * Internal getTargetStateResolver implementation for use with JDK 1.3.
177:             */
178:            private TargetStateResolver getTargetStateResolver13(
179:                    NestedRuntimeException e) {
180:                TargetStateResolver targetStateResolver;
181:                if (isRootCause13(e)) {
182:                    return findTargetStateResolver(e.getClass());
183:                } else {
184:                    targetStateResolver = (TargetStateResolver) exceptionTargetStateMappings
185:                            .get(e.getClass());
186:                    if (targetStateResolver != null) {
187:                        return targetStateResolver;
188:                    } else {
189:                        if (e.getCause() instanceof  NestedRuntimeException) {
190:                            return getTargetStateResolver13((NestedRuntimeException) e
191:                                    .getCause());
192:                        } else {
193:                            return null;
194:                        }
195:                    }
196:                }
197:            }
198:
199:            /**
200:             * Internal getTargetStateResolver implementation for use with JDK 1.4 or later.
201:             */
202:            private TargetStateResolver getTargetStateResolver14(Throwable t) {
203:                TargetStateResolver targetStateResolver;
204:                if (isRootCause14(t)) {
205:                    return findTargetStateResolver(t.getClass());
206:                } else {
207:                    targetStateResolver = (TargetStateResolver) exceptionTargetStateMappings
208:                            .get(t.getClass());
209:                    if (targetStateResolver != null) {
210:                        return targetStateResolver;
211:                    } else {
212:                        return getTargetStateResolver14(t.getCause());
213:                    }
214:                }
215:            }
216:
217:            /**
218:             * Check if given exception is the root of the exception cause chain.
219:             * For use with JDK 1.3.
220:             */
221:            private boolean isRootCause13(NestedRuntimeException e) {
222:                return e.getCause() == null;
223:            }
224:
225:            /**
226:             * Check if given exception is the root of the exception cause chain.
227:             * For use with JDK 1.4 or later.
228:             */
229:            private boolean isRootCause14(Throwable t) {
230:                return t.getCause() == null;
231:            }
232:
233:            /**
234:             * Try to find a mapped target state resolver for given exception type. Will
235:             * also try to lookup using the class hierarchy of given exception type.
236:             * @param exceptionType the exception type to lookup
237:             * @return the target state id or null if not found
238:             */
239:            private TargetStateResolver findTargetStateResolver(
240:                    Class exceptionType) {
241:                while (exceptionType != null && exceptionType != Object.class) {
242:                    if (exceptionTargetStateMappings.containsKey(exceptionType)) {
243:                        return (TargetStateResolver) exceptionTargetStateMappings
244:                                .get(exceptionType);
245:                    } else {
246:                        exceptionType = exceptionType.getSuperclass();
247:                    }
248:                }
249:                return null;
250:            }
251:
252:            /**
253:             * Find the root cause of given throwable.
254:             */
255:            protected Throwable findRootCause(Throwable t) {
256:                if (JdkVersion.getMajorJavaVersion() == JdkVersion.JAVA_13) {
257:                    return findRootCause13(t);
258:                } else {
259:                    return findRootCause14(t);
260:                }
261:            }
262:
263:            /**
264:             * Find the root cause of given throwable. For use on JDK 1.3.
265:             */
266:            private Throwable findRootCause13(Throwable t) {
267:                if (t instanceof  NestedRuntimeException) {
268:                    NestedRuntimeException nre = (NestedRuntimeException) t;
269:                    Throwable cause = nre.getCause();
270:                    if (cause == null) {
271:                        return nre;
272:                    } else {
273:                        return findRootCause13(cause);
274:                    }
275:                } else {
276:                    return t;
277:                }
278:            }
279:
280:            /**
281:             * Find the root cause of given throwable. For use on JDK 1.4 or later.
282:             */
283:            private Throwable findRootCause14(Throwable e) {
284:                Throwable cause = e.getCause();
285:                if (cause == null) {
286:                    return e;
287:                } else {
288:                    return findRootCause14(cause);
289:                }
290:            }
291:
292:            public String toString() {
293:                return new ToStringCreator(this ).append(
294:                        "exceptionTargetStateMappings",
295:                        exceptionTargetStateMappings).toString();
296:            }
297:        }
www.java2java.com | Contact Us
Copyright 2009 - 12 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.