Source Code Cross Referenced for RevolvingFileStrategy.java in  » Development » LogKit » org » apache » log » output » io » rotate » 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 » Development » LogKit » org.apache.log.output.io.rotate 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


001:        /* ====================================================================
002:         * The Apache Software License, Version 1.1
003:         *
004:         * Copyright (c) 1997-2003 The Apache Software Foundation. All rights
005:         * reserved.
006:         *
007:         * Redistribution and use in source and binary forms, with or without
008:         * modification, are permitted provided that the following conditions
009:         * are met:
010:         *
011:         * 1. Redistributions of source code must retain the above copyright
012:         *    notice, this list of conditions and the following disclaimer.
013:         *
014:         * 2. Redistributions in binary form must reproduce the above copyright
015:         *    notice, this list of conditions and the following disclaimer in
016:         *    the documentation and/or other materials provided with the
017:         *    distribution.
018:         *
019:         * 3. The end-user documentation included with the redistribution,
020:         *    if any, must include the following acknowledgment:
021:         *    "This product includes software developed by the
022:         *    Apache Software Foundation (http://www.apache.org/)."
023:         *    Alternately, this acknowledgment may appear in the software
024:         *    itself, if and wherever such third-party acknowledgments
025:         *    normally appear.
026:         *
027:         * 4. The names "Jakarta", "Avalon", and "Apache Software Foundation"
028:         *    must not be used to endorse or promote products derived from this
029:         *    software without prior written permission. For written
030:         *    permission, please contact apache@apache.org.
031:         *
032:         * 5. Products derived from this software may not be called "Apache",
033:         *    nor may "Apache" appear in their name, without prior written
034:         *    permission of the Apache Software Foundation.
035:         *
036:         * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
037:         * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
038:         * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
039:         * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
040:         * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
041:         * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
042:         * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
043:         * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
044:         * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
045:         * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
046:         * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
047:         * SUCH DAMAGE.
048:         * ====================================================================
049:         *
050:         * This software consists of voluntary contributions made by many
051:         * individuals on behalf of the Apache Software Foundation. For more
052:         * information on the Apache Software Foundation, please see
053:         * <http://www.apache.org/>.
054:         */
055:        package org.apache.log.output.io.rotate;
056:
057:        import java.io.File;
058:        import java.text.DecimalFormat;
059:        import java.text.FieldPosition;
060:        import java.text.NumberFormat;
061:
062:        /**
063:         * strategy for naming log files based on appending revolving suffix.
064:         * If the initial rotation is not specified then the class will attempt to
065:         * calculate the rotation number via the following algorithm.
066:         *
067:         * It will search for the file with the highest number in the rotation. It will
068:         * then increment its rotation number and use that number. If all files in rotation
069:         * are present then it will then set the initial rotation to the next rotation after
070:         * the most recently created file.
071:         *
072:         * @author <a href="mailto:dev@avalon.apache.org">Avalon Development Team</a>
073:         * @author <a href="mailto:bh22351@i-one.at">Bernhard Huber</a>
074:         * @author <a href="mailto:peter@apache.org">Peter Donald</a>
075:         * @author <a href="mailto:david.gray@hic.gov.au">David Gray</a>
076:         */
077:        public class RevolvingFileStrategy implements  FileStrategy {
078:            ///revolving suffix formatting pattern. ie. "'.'000000"
079:            private static final String PATTERN = "'.'000000";
080:
081:            ///a revolving suffix formatter
082:            private DecimalFormat m_decimalFormat;
083:
084:            ///current revolving suffix
085:            private int m_rotation;
086:
087:            ///max revolving value.
088:            private int m_maxRotations;
089:
090:            ///the base file name.
091:            private File m_baseFile;
092:
093:            /**
094:             * Creation of a new instane ofthe revolving file strategy.
095:             * @param baseFile the base file
096:             * @param maxRotations the maximum number of rotations ??
097:             */
098:            public RevolvingFileStrategy(final File baseFile,
099:                    final int maxRotations) {
100:                this (baseFile, -1, maxRotations);
101:            }
102:
103:            /**
104:             * Creation of a new instane ofthe revolving file strategy.
105:             * @param baseFile the base file
106:             * @param initialRotation the number of initial rotations ??
107:             * @param maxRotations the maximum number of rotations?? 
108:             */
109:            public RevolvingFileStrategy(final File baseFile,
110:                    final int initialRotation, final int maxRotations) {
111:                m_decimalFormat = new DecimalFormat(PATTERN);
112:
113:                m_baseFile = baseFile;
114:                m_rotation = initialRotation;
115:                m_maxRotations = maxRotations;
116:
117:                if (-1 == m_maxRotations) {
118:                    m_maxRotations = Integer.MAX_VALUE;
119:                }
120:
121:                if (-1 == initialRotation) {
122:                    m_rotation = calculateInitialRotation();
123:                }
124:
125:                if (m_rotation > m_maxRotations) {
126:                    m_rotation = m_maxRotations;
127:                }
128:
129:                if (m_rotation < 0) {
130:                    m_rotation = 0;
131:                }
132:            }
133:
134:            /**
135:             * Calculate the real file name from the base filename.
136:             *
137:             * @return File the calculated file name
138:             */
139:            public File nextFile() {
140:                final StringBuffer sb = new StringBuffer();
141:                final FieldPosition position = new FieldPosition(
142:                        NumberFormat.INTEGER_FIELD);
143:                sb.append(m_baseFile);
144:
145:                final StringBuffer result = m_decimalFormat.format(m_rotation,
146:                        sb, position);
147:                m_rotation += 1;
148:
149:                if (m_rotation >= m_maxRotations) {
150:                    m_rotation = 0;
151:                }
152:
153:                return new File(result.toString());
154:            }
155:
156:            /**
157:             * Retrieve the current rotation number.
158:             *
159:             * @return the current rotation number.
160:             */
161:            public int getCurrentRotation() {
162:                return m_rotation;
163:            }
164:
165:            /**
166:             * Method that searches through files that
167:             * match the pattern for resolving file and determine
168:             * the last generation written to.
169:             *
170:             * @return the initial rotation
171:             */
172:            private int calculateInitialRotation() {
173:                final File[] matchingFiles = getMatchingFiles();
174:                if (null == matchingFiles || 0 == matchingFiles.length) {
175:                    return 0;
176:                }
177:
178:                final int[] rotations = calculateRotations(matchingFiles);
179:
180:                //First we go through and look for maximumRotation
181:                int maxRotation = 0;
182:                for (int i = 0; i < rotations.length; i++) {
183:                    final int rotation = rotations[i];
184:                    if (rotation > maxRotation) {
185:                        maxRotation = rotation;
186:                    }
187:                }
188:
189:                //If the max rotation present on filessytem
190:                //is less than max rotation possible then return that
191:                //rotation
192:                if (m_maxRotations != maxRotation) {
193:                    return maxRotation + 1;
194:                }
195:
196:                //Okay now we need to calculate the youngest file for our rotation
197:                long time = matchingFiles[0].lastModified();
198:
199:                //index of oldest file
200:                int oldest = rotations[0];
201:                for (int i = 0; i < matchingFiles.length; i++) {
202:                    final File file = matchingFiles[i];
203:                    final long lastModified = file.lastModified();
204:                    if (lastModified < time) {
205:                        time = lastModified;
206:                        oldest = rotations[i];
207:                    }
208:                }
209:
210:                return oldest;
211:            }
212:
213:            /**
214:             * Generate an array of rotation numbers for all the files specified.
215:             *
216:             * @param matchingFiles the files to generate rotation numbers for
217:             * @return the array containing rotations
218:             */
219:            private int[] calculateRotations(final File[] matchingFiles) {
220:                final int[] results = new int[matchingFiles.length];
221:
222:                for (int i = 0; i < matchingFiles.length; i++) {
223:                    final File file = matchingFiles[i];
224:
225:                    // The files may be returned in any order
226:                    //therefore calc the rotation number
227:                    try {
228:                        results[i] = calculateRotationForFile(file);
229:                    } catch (final NumberFormatException nfe) {
230:                        //If bad log file detected then set to -1
231:                        results[i] = -1;
232:                    }
233:                }
234:                return results;
235:            }
236:
237:            /**
238:             * Return the rotation for the specified file
239:             *
240:             * @param file the file to check
241:             * @return the rotation of the file
242:             */
243:            private int calculateRotationForFile(final File file) {
244:                final String filename = file.toString();
245:                final int length = filename.length();
246:                final int minDigits = m_decimalFormat.getMinimumIntegerDigits();
247:                final String rotation = filename.substring(length - minDigits);
248:
249:                return Integer.parseInt(rotation);
250:            }
251:
252:            /**
253:             * Get a list of files that could have been part of the rotation.
254:             *
255:             * @return the list of files that match
256:             */
257:            private File[] getMatchingFiles() {
258:                // First get the path of the base file. Note that this path includes
259:                // the path and the base of the file name itself.
260:                final String fullFilePathName = m_baseFile.getPath();
261:
262:                // Try to find the last path separator (if it exists)
263:                final int fileSeparatorPosition = fullFilePathName
264:                        .lastIndexOf(File.separator);
265:
266:                // If the last path separator does not exist the baseFile is a pure file name
267:                File basePath;
268:                String baseFileName;
269:                if (fileSeparatorPosition < 0) {
270:                    // assume the current directory
271:                    basePath = new File(".");
272:                    baseFileName = fullFilePathName;
273:                } else {
274:                    // Extract the sub-directory structure
275:                    String m_parentPath = fullFilePathName.substring(0,
276:                            fileSeparatorPosition);
277:                    baseFileName = fullFilePathName
278:                            .substring(fileSeparatorPosition + 1);
279:                    basePath = new File(m_parentPath);
280:                }
281:
282:                return basePath.listFiles(new BaseFileNameFilter(baseFileName));
283:            }
284:        }
www.java2java.com | Contact Us
Copyright 2009 - 12 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.