Source Code Cross Referenced for Log4jWebConfigurer.java in  » J2EE » spring-framework-2.0.6 » org » springframework » web » util » 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 » J2EE » spring framework 2.0.6 » org.springframework.web.util 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


001:        /*
002:         * Copyright 2002-2005 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:
017:        package org.springframework.web.util;
018:
019:        import java.io.FileNotFoundException;
020:
021:        import javax.servlet.ServletContext;
022:
023:        import org.springframework.util.Log4jConfigurer;
024:        import org.springframework.util.ResourceUtils;
025:        import org.springframework.util.SystemPropertyUtils;
026:
027:        /**
028:         * Convenience class that performs custom Log4J initialization for web environments,
029:         * allowing for log file paths within the web application, with the option to
030:         * perform automatic refresh checks (for runtime changes in logging configuration).
031:         *
032:         * <p><b>WARNING: Assumes an expanded WAR file</b>, both for loading the configuration
033:         * file and for writing the log files. If you want to keep your WAR unexpanded or
034:         * don't need application-specific log files within the WAR directory, don't use
035:         * Log4J setup within the application (thus, don't use Log4jConfigListener or
036:         * Log4jConfigServlet). Instead, use a global, VM-wide Log4J setup (for example,
037:         * in JBoss) or JDK 1.4's <code>java.util.logging</code> (which is global too).
038:         *
039:         * <p>Supports three init parameters at the servlet context level (that is,
040:         * context-param entries in web.xml):
041:         *
042:         * <ul>
043:         * <li><i>"log4jConfigLocation":</i><br>
044:         * Location of the Log4J config file; either a "classpath:" location (e.g.
045:         * "classpath:myLog4j.properties"), an absolute file URL (e.g. "file:C:/log4j.properties),
046:         * or a plain path relative to the web application root directory (e.g.
047:         * "/WEB-INF/log4j.properties"). If not specified, default Log4J initialization will
048:         * apply ("log4j.properties" in the class path; see Log4J documentation for details).
049:         * <li><i>"log4jRefreshInterval":</i><br>
050:         * Interval between config file refresh checks, in milliseconds. If not specified,
051:         * no refresh checks will happen, which avoids starting Log4J's watchdog thread.
052:         * <li><i>"log4jExposeWebAppRoot":</i><br>
053:         * Whether the web app root system property should be exposed, allowing for log
054:         * file paths relative to the web application root directory. Default is "true";
055:         * specify "false" to suppress expose of the web app root system property. See
056:         * below for details on how to use this system property in log file locations.
057:         * </ul>
058:         *
059:         * <p>Note: <code>initLogging</code> should be called before any other Spring activity
060:         * (when using Log4J), for proper initialization before any Spring logging attempts.
061:         *
062:         * <p>Log4J's watchdog thread will asynchronously check whether the timestamp
063:         * of the config file has changed, using the given interval between checks.
064:         * A refresh interval of 1000 milliseconds (one second), which allows to
065:         * do on-demand log level changes with immediate effect, is not unfeasible.
066:
067:         * <p><b>WARNING:</b> Log4J's watchdog thread does not terminate until VM shutdown;
068:         * in particular, it does not terminate on LogManager shutdown. Therefore, it is
069:         * recommended to <i>not</i> use config file refreshing in a production J2EE
070:         * environment; the watchdog thread would not stop on application shutdown there.
071:         *
072:         * <p>By default, this configurer automatically sets the web app root system property,
073:         * for "${key}" substitutions within log file locations in the Log4J config file,
074:         * allowing for log file paths relative to the web application root directory.
075:         * The default system property key is "webapp.root", to be used in a Log4J config
076:         * file like as follows:
077:         *
078:         * <p><code>log4j.appender.myfile.File=${webapp.root}/WEB-INF/demo.log</code>
079:         *
080:         * <p>Alternatively, specify a unique context-param "webAppRootKey" per web application.
081:         * For example, with "webAppRootKey = "demo.root":
082:         *
083:         * <p><code>log4j.appender.myfile.File=${demo.root}/WEB-INF/demo.log</code>
084:         *
085:         * <p><b>WARNING:</b> Some containers (like Tomcat) do <i>not</i> keep system properties
086:         * separate per web app. You have to use unique "webAppRootKey" context-params per web
087:         * app then, to avoid clashes. Other containers like Resin do isolate each web app's
088:         * system properties: Here you can use the default key (i.e. no "webAppRootKey"
089:         * context-param at all) without worrying.
090:         *
091:         * @author Juergen Hoeller
092:         * @since 12.08.2003
093:         * @see org.springframework.util.Log4jConfigurer
094:         * @see Log4jConfigListener
095:         * @see Log4jConfigServlet
096:         */
097:        public abstract class Log4jWebConfigurer {
098:
099:            /** Parameter specifying the location of the Log4J config file */
100:            public static final String CONFIG_LOCATION_PARAM = "log4jConfigLocation";
101:
102:            /** Parameter specifying the refresh interval for checking the Log4J config file */
103:            public static final String REFRESH_INTERVAL_PARAM = "log4jRefreshInterval";
104:
105:            /** Parameter specifying whether to expose the web app root system property */
106:            public static final String EXPOSE_WEB_APP_ROOT_PARAM = "log4jExposeWebAppRoot";
107:
108:            /**
109:             * Initialize Log4J, including setting the web app root system property.
110:             * @param servletContext the current ServletContext
111:             * @see WebUtils#setWebAppRootSystemProperty
112:             */
113:            public static void initLogging(ServletContext servletContext) {
114:                // Expose the web app root system property.
115:                if (exposeWebAppRoot(servletContext)) {
116:                    WebUtils.setWebAppRootSystemProperty(servletContext);
117:                }
118:
119:                // Only perform custom Log4J initialization in case of a config file.
120:                String location = servletContext
121:                        .getInitParameter(CONFIG_LOCATION_PARAM);
122:                if (location != null) {
123:                    // Perform actual Log4J initialization; else rely on Log4J's default initialization.
124:                    try {
125:                        // Return a URL (e.g. "classpath:" or "file:") as-is;
126:                        // consider a plain file path as relative to the web application root directory.
127:                        if (!ResourceUtils.isUrl(location)) {
128:                            // Resolve system property placeholders before resolving real path.
129:                            location = SystemPropertyUtils
130:                                    .resolvePlaceholders(location);
131:                            location = WebUtils.getRealPath(servletContext,
132:                                    location);
133:                        }
134:
135:                        // Write log message to server log.
136:                        servletContext.log("Initializing Log4J from ["
137:                                + location + "]");
138:
139:                        // Check whether refresh interval was specified.
140:                        String intervalString = servletContext
141:                                .getInitParameter(REFRESH_INTERVAL_PARAM);
142:                        if (intervalString != null) {
143:                            // Initialize with refresh interval, i.e. with Log4J's watchdog thread,
144:                            // checking the file in the background.
145:                            try {
146:                                long refreshInterval = Long
147:                                        .parseLong(intervalString);
148:                                Log4jConfigurer.initLogging(location,
149:                                        refreshInterval);
150:                            } catch (NumberFormatException ex) {
151:                                throw new IllegalArgumentException(
152:                                        "Invalid 'log4jRefreshInterval' parameter: "
153:                                                + ex.getMessage());
154:                            }
155:                        } else {
156:                            // Initialize without refresh check, i.e. without Log4J's watchdog thread.
157:                            Log4jConfigurer.initLogging(location);
158:                        }
159:                    } catch (FileNotFoundException ex) {
160:                        throw new IllegalArgumentException(
161:                                "Invalid 'log4jConfigLocation' parameter: "
162:                                        + ex.getMessage());
163:                    }
164:                }
165:            }
166:
167:            /**
168:             * Shut down Log4J, properly releasing all file locks
169:             * and resetting the web app root system property.
170:             * @param servletContext the current ServletContext
171:             * @see WebUtils#removeWebAppRootSystemProperty
172:             */
173:            public static void shutdownLogging(ServletContext servletContext) {
174:                servletContext.log("Shutting down Log4J");
175:                try {
176:                    Log4jConfigurer.shutdownLogging();
177:                } finally {
178:                    // Remove the web app root system property.
179:                    if (exposeWebAppRoot(servletContext)) {
180:                        WebUtils.removeWebAppRootSystemProperty(servletContext);
181:                    }
182:                }
183:            }
184:
185:            /**
186:             * Return whether to expose the web app root system property,
187:             * checking the corresponding ServletContext init parameter.
188:             * @see #EXPOSE_WEB_APP_ROOT_PARAM
189:             */
190:            private static boolean exposeWebAppRoot(
191:                    ServletContext servletContext) {
192:                String exposeWebAppRootParam = servletContext
193:                        .getInitParameter(EXPOSE_WEB_APP_ROOT_PARAM);
194:                return (exposeWebAppRootParam == null || Boolean.valueOf(
195:                        exposeWebAppRootParam).booleanValue());
196:            }
197:
198:        }
www.java2java.com | Contact Us
Copyright 2009 - 12 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.