001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache license, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the license for the specific language governing permissions and 015 * limitations under the license. 016 */ 017package org.apache.logging.log4j.core.appender; 018 019import java.io.BufferedOutputStream; 020import java.io.File; 021import java.io.FileNotFoundException; 022import java.io.FileOutputStream; 023import java.io.IOException; 024import java.io.OutputStream; 025import java.io.Serializable; 026import java.nio.channels.FileChannel; 027import java.nio.channels.FileLock; 028import java.util.HashMap; 029import java.util.Map; 030 031import org.apache.logging.log4j.core.Layout; 032 033 034/** 035 * Manages actual File I/O for File Appenders. 036 */ 037public class FileManager extends OutputStreamManager { 038 039 private static final FileManagerFactory FACTORY = new FileManagerFactory(); 040 041 private final boolean isAppend; 042 private final boolean isLocking; 043 private final String advertiseURI; 044 private final int bufferSize; 045 046 protected FileManager(final String fileName, final OutputStream os, final boolean append, final boolean locking, 047 final String advertiseURI, final Layout<? extends Serializable> layout, final int bufferSize, 048 final boolean writeHeader) { 049 super(os, fileName, layout, writeHeader); 050 this.isAppend = append; 051 this.isLocking = locking; 052 this.advertiseURI = advertiseURI; 053 this.bufferSize = bufferSize; 054 } 055 056 /** 057 * Returns the FileManager. 058 * @param fileName The name of the file to manage. 059 * @param append true if the file should be appended to, false if it should be overwritten. 060 * @param locking true if the file should be locked while writing, false otherwise. 061 * @param bufferedIo true if the contents should be buffered as they are written. 062 * @param advertiseUri the URI to use when advertising the file 063 * @param layout The layout 064 * @param bufferSize buffer size for buffered IO 065 * @return A FileManager for the File. 066 */ 067 public static FileManager getFileManager(final String fileName, final boolean append, boolean locking, 068 final boolean bufferedIo, final String advertiseUri, final Layout<? extends Serializable> layout, 069 final int bufferSize) { 070 071 if (locking && bufferedIo) { 072 locking = false; 073 } 074 return (FileManager) getManager(fileName, new FactoryData(append, locking, bufferedIo, bufferSize, 075 advertiseUri, layout), FACTORY); 076 } 077 078 @Override 079 protected synchronized void write(final byte[] bytes, final int offset, final int length) { 080 081 if (isLocking) { 082 final FileChannel channel = ((FileOutputStream) getOutputStream()).getChannel(); 083 try { 084 /* Lock the whole file. This could be optimized to only lock from the current file 085 position. Note that locking may be advisory on some systems and mandatory on others, 086 so locking just from the current position would allow reading on systems where 087 locking is mandatory. Also, Java 6 will throw an exception if the region of the 088 file is already locked by another FileChannel in the same JVM. Hopefully, that will 089 be avoided since every file should have a single file manager - unless two different 090 files strings are configured that somehow map to the same file.*/ 091 final FileLock lock = channel.lock(0, Long.MAX_VALUE, false); 092 try { 093 super.write(bytes, offset, length); 094 } finally { 095 lock.release(); 096 } 097 } catch (final IOException ex) { 098 throw new AppenderLoggingException("Unable to obtain lock on " + getName(), ex); 099 } 100 101 } else { 102 super.write(bytes, offset, length); 103 } 104 } 105 106 /** 107 * Returns the name of the File being managed. 108 * @return The name of the File being managed. 109 */ 110 public String getFileName() { 111 return getName(); 112 } 113 114 /** 115 * Returns the append status. 116 * @return true if the file will be appended to, false if it is overwritten. 117 */ 118 public boolean isAppend() { 119 return isAppend; 120 } 121 122 /** 123 * Returns the lock status. 124 * @return true if the file will be locked when writing, false otherwise. 125 */ 126 public boolean isLocking() { 127 return isLocking; 128 } 129 130 /** 131 * Returns the buffer size to use if the appender was configured with BufferedIO=true, otherwise returns a negative 132 * number. 133 * @return the buffer size, or a negative number if the output stream is not buffered 134 */ 135 public int getBufferSize() { 136 return bufferSize; 137 } 138 139 /** 140 * FileManager's content format is specified by: <code>Key: "fileURI" Value: provided "advertiseURI" param</code>. 141 * 142 * @return Map of content format keys supporting FileManager 143 */ 144 @Override 145 public Map<String, String> getContentFormat() { 146 final Map<String, String> result = new HashMap<>(super.getContentFormat()); 147 result.put("fileURI", advertiseURI); 148 return result; 149 } 150 151 /** 152 * Factory Data. 153 */ 154 private static class FactoryData { 155 private final boolean append; 156 private final boolean locking; 157 private final boolean bufferedIO; 158 private final int bufferSize; 159 private final String advertiseURI; 160 private final Layout<? extends Serializable> layout; 161 162 /** 163 * Constructor. 164 * @param append Append status. 165 * @param locking Locking status. 166 * @param bufferedIO Buffering flag. 167 * @param bufferSize Buffer size. 168 * @param advertiseURI the URI to use when advertising the file 169 */ 170 public FactoryData(final boolean append, final boolean locking, final boolean bufferedIO, final int bufferSize, 171 final String advertiseURI, final Layout<? extends Serializable> layout) { 172 this.append = append; 173 this.locking = locking; 174 this.bufferedIO = bufferedIO; 175 this.bufferSize = bufferSize; 176 this.advertiseURI = advertiseURI; 177 this.layout = layout; 178 } 179 } 180 181 /** 182 * Factory to create a FileManager. 183 */ 184 private static class FileManagerFactory implements ManagerFactory<FileManager, FactoryData> { 185 186 /** 187 * Create a FileManager. 188 * @param name The name of the File. 189 * @param data The FactoryData 190 * @return The FileManager for the File. 191 */ 192 @Override 193 public FileManager createManager(final String name, final FactoryData data) { 194 final File file = new File(name); 195 final File parent = file.getParentFile(); 196 if (null != parent && !parent.exists()) { 197 parent.mkdirs(); 198 } 199 200 final boolean writeHeader = !data.append || !file.exists(); 201 OutputStream os; 202 try { 203 os = new FileOutputStream(name, data.append); 204 int bufferSize = data.bufferSize; 205 if (data.bufferedIO) { 206 os = new BufferedOutputStream(os, bufferSize); 207 } else { 208 bufferSize = -1; // signals to RollingFileManager not to use BufferedOutputStream 209 } 210 return new FileManager(name, os, data.append, data.locking, data.advertiseURI, data.layout, bufferSize, 211 writeHeader); 212 } catch (final FileNotFoundException ex) { 213 LOGGER.error("FileManager (" + name + ") " + ex, ex); 214 } 215 return null; 216 } 217 } 218 219}