001 package org.apache.archiva.transaction;
002
003 /*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements. See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership. The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License. You may obtain a copy of the License at
011 *
012 * http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied. See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022 import org.apache.commons.io.FileUtils;
023 import org.codehaus.plexus.digest.Digester;
024 import org.codehaus.plexus.digest.DigesterException;
025
026 import java.io.File;
027 import java.io.IOException;
028 import java.util.ArrayList;
029 import java.util.Collections;
030 import java.util.HashMap;
031 import java.util.Iterator;
032 import java.util.List;
033 import java.util.Map;
034
035 /**
036 * Abstract class for the TransactionEvents
037 *
038 *
039 */
040 public abstract class AbstractTransactionEvent
041 implements TransactionEvent
042 {
043 private Map<File, File> backups = new HashMap<File, File>();
044
045 private List<File> createdDirs = new ArrayList<File>();
046
047 private List<File> createdFiles = new ArrayList<File>();
048
049 /**
050 * {@link List}<{@link Digester}>
051 */
052 private List<? extends Digester> digesters;
053
054 protected AbstractTransactionEvent()
055 {
056 this( new ArrayList<Digester>( 0 ) );
057 }
058
059 protected AbstractTransactionEvent( List<? extends Digester> digesters )
060 {
061 this.digesters = digesters;
062 }
063
064 protected List<? extends Digester> getDigesters()
065 {
066 return digesters;
067 }
068
069 /**
070 * Method that creates a directory as well as all the parent directories needed
071 *
072 * @param dir The File directory to be created
073 * @throws IOException when an unrecoverable error occurred
074 */
075 protected void mkDirs( File dir )
076 throws IOException
077 {
078 List<File> createDirs = new ArrayList<File>();
079
080 File parent = dir;
081 while ( !parent.exists() || !parent.isDirectory() )
082 {
083 createDirs.add( parent );
084
085 parent = parent.getParentFile();
086 }
087
088 while ( !createDirs.isEmpty() )
089 {
090 File directory = (File) createDirs.remove( createDirs.size() - 1 );
091
092 if ( directory.mkdir() )
093 {
094 createdDirs.add( directory );
095 }
096 else
097 {
098 throw new IOException( "Failed to create directory: " + directory.getAbsolutePath() );
099 }
100 }
101 }
102
103 protected void revertMkDirs()
104 throws IOException
105 {
106 if ( createdDirs != null )
107 {
108 Collections.reverse( createdDirs );
109
110 while ( !createdDirs.isEmpty() )
111 {
112 File dir = (File) createdDirs.remove( 0 );
113
114 if ( dir.isDirectory() && dir.list().length == 0 )
115 {
116 FileUtils.deleteDirectory( dir );
117 }
118 else
119 {
120 //cannot rollback created directory if it still contains files
121 break;
122 }
123 }
124 }
125 }
126
127 protected void revertFilesCreated()
128 throws IOException
129 {
130 Iterator<File> it = createdFiles.iterator();
131 while ( it.hasNext() )
132 {
133 File file = (File) it.next();
134 file.delete();
135 it.remove();
136 }
137 }
138
139 protected void createBackup( File file )
140 throws IOException
141 {
142 if ( file.exists() && file.isFile() )
143 {
144 File backup = File.createTempFile( "temp-", ".backup" );
145
146 FileUtils.copyFile( file, backup );
147
148 backup.deleteOnExit();
149
150 backups.put( file, backup );
151 }
152 }
153
154 protected void restoreBackups()
155 throws IOException
156 {
157 for ( Map.Entry<File, File> entry : backups.entrySet() )
158 {
159 FileUtils.copyFile( entry.getValue(), entry.getKey() );
160 }
161 }
162
163 protected void restoreBackup( File file )
164 throws IOException
165 {
166 File backup = (File) backups.get( file );
167 if ( backup != null )
168 {
169 FileUtils.copyFile( backup, file );
170 }
171 }
172
173 /**
174 * Create checksums of file using all digesters defined at construction time.
175 *
176 * @param file
177 * @param force whether existing checksums should be overwritten or not
178 * @throws IOException
179 */
180 protected void createChecksums( File file, boolean force )
181 throws IOException
182 {
183 for ( Digester digester : getDigesters() )
184 {
185 File checksumFile = new File( file.getAbsolutePath() + "." + getDigesterFileExtension( digester ) );
186 if ( checksumFile.exists() )
187 {
188 if ( !force )
189 {
190 continue;
191 }
192 createBackup( checksumFile );
193 }
194 else
195 {
196 createdFiles.add( checksumFile );
197 }
198
199 try
200 {
201 writeStringToFile( checksumFile, digester.calc( file ) );
202 }
203 catch ( DigesterException e )
204 {
205 throw (IOException) e.getCause();
206 }
207 }
208 }
209
210 /**
211 * TODO: Remove in favor of using FileUtils directly.
212 */
213 protected void writeStringToFile( File file, String content )
214 throws IOException
215 {
216 FileUtils.writeStringToFile( file, content );
217 }
218
219 /**
220 * File extension for checksums
221 * TODO should be moved to plexus-digester ?
222 */
223 protected String getDigesterFileExtension( Digester digester )
224 {
225 return digester.getAlgorithm().toLowerCase().replaceAll( "-", "" );
226 }
227
228 }