| 1 | /* |
| 2 | |
| 3 | Derby - Class org.apache.derby.impl.io.DirStorageFactory |
| 4 | |
| 5 | Copyright 2004 The Apache Software Foundation or its licensors, as applicable. |
| 6 | |
| 7 | Licensed under the Apache License, Version 2.0 (the "License"); |
| 8 | you may not use this file except in compliance with the License. |
| 9 | You may obtain a copy of the License at |
| 10 | |
| 11 | http://www.apache.org/licenses/LICENSE-2.0 |
| 12 | |
| 13 | Unless required by applicable law or agreed to in writing, software |
| 14 | distributed under the License is distributed on an "AS IS" BASIS, |
| 15 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 16 | See the License for the specific language governing permissions and |
| 17 | limitations under the License. |
| 18 | |
| 19 | */ |
| 20 | |
| 21 | package org.apache.derby.impl.io; |
| 22 | |
| 23 | import org.apache.derby.iapi.services.sanity.SanityManager; |
| 24 | |
| 25 | import org.apache.derby.io.WritableStorageFactory; |
| 26 | import org.apache.derby.io.StorageFile; |
| 27 | import org.apache.derby.io.StorageRandomAccessFile; |
| 28 | |
| 29 | import java.io.File; |
| 30 | import java.io.FileNotFoundException; |
| 31 | import java.io.FileOutputStream; |
| 32 | import java.io.FileInputStream; |
| 33 | import java.io.InputStream; |
| 34 | import java.io.OutputStream; |
| 35 | import java.io.IOException; |
| 36 | import java.io.SyncFailedException; |
| 37 | |
| 38 | import java.util.Properties; |
| 39 | |
| 40 | /** |
| 41 | * This class provides a disk based implementation of the StorageFactory interface. It is used by the |
| 42 | * database engine to access persistent data and transaction logs under the directory (default) subsubprotocol. |
| 43 | */ |
| 44 | |
| 45 | public class DirStorageFactory extends BaseStorageFactory |
| 46 | implements WritableStorageFactory |
| 47 | { |
| 48 | /** |
| 49 | * Construct a StorageFile from a path name. |
| 50 | * |
| 51 | * @param path The path name of the file |
| 52 | * |
| 53 | * @return A corresponding StorageFile object |
| 54 | */ |
| 55 | public final StorageFile newStorageFile( String path) |
| 56 | { |
| 57 | return newPersistentFile( path); |
| 58 | } |
| 59 | |
| 60 | /** |
| 61 | * Construct a StorageFile from a directory and file name. |
| 62 | * |
| 63 | * @param directoryName The directory part of the path name. |
| 64 | * @param fileName The name of the file within the directory. |
| 65 | * |
| 66 | * @return A corresponding StorageFile object |
| 67 | */ |
| 68 | public final StorageFile newStorageFile( String directoryName, String fileName) |
| 69 | { |
| 70 | return newPersistentFile( directoryName, fileName); |
| 71 | } |
| 72 | |
| 73 | /** |
| 74 | * Construct a StorageFile from a directory and file name. |
| 75 | * |
| 76 | * @param directoryName The directory part of the path name. |
| 77 | * @param fileName The name of the file within the directory. |
| 78 | * |
| 79 | * @return A corresponding StorageFile object |
| 80 | */ |
| 81 | public final StorageFile newStorageFile( StorageFile directoryName, String fileName) |
| 82 | { |
| 83 | return newPersistentFile( directoryName, fileName); |
| 84 | } |
| 85 | /** |
| 86 | * Construct a persistent StorageFile from a path name. |
| 87 | * |
| 88 | * @param path The path name of the file. Guaranteed not to be in the temporary file directory. If null |
| 89 | * then the database directory should be returned. |
| 90 | * |
| 91 | * @return A corresponding StorageFile object |
| 92 | */ |
| 93 | StorageFile newPersistentFile( String path) |
| 94 | { |
| 95 | if( path == null) |
| 96 | return new DirFile( dataDirectory); |
| 97 | return new DirFile(dataDirectory, path); |
| 98 | } |
| 99 | |
| 100 | /** |
| 101 | * Construct a persistent StorageFile from a directory and path name. |
| 102 | * |
| 103 | * @param directoryName The path name of the directory. Guaranteed not to be in the temporary file directory. |
| 104 | * Guaranteed not to be null |
| 105 | * @param fileName The name of the file within the directory. Guaranteed not to be null. |
| 106 | * |
| 107 | * @return A corresponding StorageFile object |
| 108 | */ |
| 109 | StorageFile newPersistentFile( String directoryName, String fileName) |
| 110 | { |
| 111 | return new DirFile( separatedDataDirectory + directoryName, fileName); |
| 112 | } |
| 113 | |
| 114 | /** |
| 115 | * Construct a persistent StorageFile from a directory and path name. |
| 116 | * |
| 117 | * @param directoryName The path name of the directory. Guaranteed not to be to be null. Guaranteed to be |
| 118 | * created by a call to one of the newPersistentFile methods. |
| 119 | * @param fileName The name of the file within the directory. Guaranteed not to be null. |
| 120 | * |
| 121 | * @return A corresponding StorageFile object |
| 122 | */ |
| 123 | StorageFile newPersistentFile( StorageFile directoryName, String fileName) |
| 124 | { |
| 125 | return new DirFile( (DirFile) directoryName, fileName); |
| 126 | } |
| 127 | |
| 128 | /** |
| 129 | * Force the data of an output stream out to the underlying storage. That is, ensure that |
| 130 | * it has been made persistent. If the database is to be transient, that is, if the database |
| 131 | * does not survive a restart, then the sync method implementation need not do anything. |
| 132 | * |
| 133 | * @param stream The stream to be synchronized. |
| 134 | * @param metaData If true then this method must force both changes to the file's |
| 135 | * contents and metadata to be written to storage; if false, it need only force file content changes |
| 136 | * to be written. The implementation is allowed to ignore this parameter and always force out |
| 137 | * metadata changes. |
| 138 | * |
| 139 | * @exception IOException if an I/O error occurs. |
| 140 | * @exception SyncFailedException Thrown when the buffers cannot be flushed, |
| 141 | * or because the system cannot guarantee that all the buffers have been |
| 142 | * synchronized with physical media. |
| 143 | */ |
| 144 | public void sync( OutputStream stream, boolean metaData) throws IOException, SyncFailedException |
| 145 | { |
| 146 | ((FileOutputStream) stream).getFD().sync(); |
| 147 | } |
| 148 | |
| 149 | /** |
| 150 | * This method tests whether the "rws" and "rwd" modes are implemented. If the "rws" method is supported |
| 151 | * then the database engine will conclude that the write methods of "rws" mode StorageRandomAccessFiles are |
| 152 | * slow but the sync method is fast and optimize accordingly. |
| 153 | * |
| 154 | * @return <b>true</b> if an StIRandomAccess file opened with "rws" or "rwd" modes immediately writes data to the |
| 155 | * underlying storage, <b>false</b> if not. |
| 156 | */ |
| 157 | public boolean supportsRws() |
| 158 | { |
| 159 | return false; |
| 160 | } |
| 161 | |
| 162 | public boolean isReadOnlyDatabase() |
| 163 | { |
| 164 | return false; |
| 165 | } |
| 166 | |
| 167 | /** |
| 168 | * Determine whether the storage supports random access. If random access is not supported then |
| 169 | * it will only be accessed using InputStreams and OutputStreams (if the database is writable). |
| 170 | * |
| 171 | * @return <b>true</b> if the storage supports random access, <b>false</b> if it is writable. |
| 172 | */ |
| 173 | public boolean supportsRandomAccess() |
| 174 | { |
| 175 | return true; |
| 176 | } |
| 177 | |
| 178 | void doInit() throws IOException |
| 179 | { |
| 180 | if( dataDirectory != null) |
| 181 | { |
| 182 | File dataDirectoryFile = new File( dataDirectory); |
| 183 | File databaseRoot = null; |
| 184 | if( dataDirectoryFile.isAbsolute()) |
| 185 | databaseRoot = dataDirectoryFile; |
| 186 | else if( home != null && dataDirectory.startsWith( home)) |
| 187 | databaseRoot = dataDirectoryFile; |
| 188 | else |
| 189 | databaseRoot = new File( home, dataDirectory); |
| 190 | canonicalName = databaseRoot.getCanonicalPath(); |
| 191 | createTempDir(); |
| 192 | separatedDataDirectory = dataDirectory + getSeparator(); |
| 193 | } |
| 194 | else if( home != null) |
| 195 | { |
| 196 | File root = new File( home); |
| 197 | dataDirectory = root.getCanonicalPath(); |
| 198 | separatedDataDirectory = dataDirectory + getSeparator(); |
| 199 | } |
| 200 | } // end of doInit |
| 201 | } |