| 1 | /* |
| 2 | Copyright (C) 2004 MySQL AB |
| 3 | |
| 4 | This program is free software; you can redistribute it and/or modify |
| 5 | it under the terms of version 2 of the GNU General Public License as |
| 6 | published by the Free Software Foundation. |
| 7 | |
| 8 | There are special exceptions to the terms and conditions of the GPL |
| 9 | as it is applied to this software. View the full text of the |
| 10 | exception in file EXCEPTIONS-CONNECTOR-J in the directory of this |
| 11 | software distribution. |
| 12 | |
| 13 | This program is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with this program; if not, write to the Free Software |
| 20 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 21 | */ |
| 22 | package com.mysql.jdbc; |
| 23 | |
| 24 | import java.sql.CallableStatement; |
| 25 | import java.sql.DatabaseMetaData; |
| 26 | import java.sql.PreparedStatement; |
| 27 | import java.sql.SQLException; |
| 28 | import java.sql.SQLWarning; |
| 29 | import java.sql.Savepoint; |
| 30 | import java.sql.Statement; |
| 31 | import java.util.Map; |
| 32 | import java.util.Properties; |
| 33 | |
| 34 | /** |
| 35 | * Connection that opens two connections, one two a replication master, and |
| 36 | * another to one or more slaves, and decides to use master when the connection |
| 37 | * is not read-only, and use slave(s) when the connection is read-only. |
| 38 | * |
| 39 | * @version $Id: ReplicationConnection.java,v 1.1.2.1 2005/05/13 18:58:38 |
| 40 | * mmatthews Exp $ |
| 41 | */ |
| 42 | public class ReplicationConnection implements java.sql.Connection { |
| 43 | private Connection currentConnection; |
| 44 | |
| 45 | private Connection masterConnection; |
| 46 | |
| 47 | private Connection slavesConnection; |
| 48 | |
| 49 | public ReplicationConnection(Properties masterProperties, |
| 50 | Properties slaveProperties) throws SQLException { |
| 51 | Driver driver = new Driver(); |
| 52 | |
| 53 | StringBuffer masterUrl = new StringBuffer("jdbc:mysql://"); |
| 54 | StringBuffer slaveUrl = new StringBuffer("jdbc:mysql://"); |
| 55 | |
| 56 | String masterHost = masterProperties |
| 57 | .getProperty(NonRegisteringDriver.HOST_PROPERTY_KEY); |
| 58 | |
| 59 | if (masterHost != null) { |
| 60 | masterUrl.append(masterHost); |
| 61 | } |
| 62 | |
| 63 | String slaveHost = slaveProperties |
| 64 | .getProperty(NonRegisteringDriver.HOST_PROPERTY_KEY); |
| 65 | |
| 66 | if (slaveHost != null) { |
| 67 | slaveUrl.append(slaveHost); |
| 68 | } |
| 69 | |
| 70 | String masterDb = masterProperties |
| 71 | .getProperty(NonRegisteringDriver.DBNAME_PROPERTY_KEY); |
| 72 | |
| 73 | masterUrl.append("/"); |
| 74 | |
| 75 | if (masterDb != null) { |
| 76 | masterUrl.append(masterDb); |
| 77 | } |
| 78 | |
| 79 | String slaveDb = slaveProperties |
| 80 | .getProperty(NonRegisteringDriver.DBNAME_PROPERTY_KEY); |
| 81 | |
| 82 | slaveUrl.append("/"); |
| 83 | |
| 84 | if (slaveDb != null) { |
| 85 | slaveUrl.append(slaveDb); |
| 86 | } |
| 87 | |
| 88 | this.masterConnection = (com.mysql.jdbc.Connection) driver.connect( |
| 89 | masterUrl.toString(), masterProperties); |
| 90 | this.slavesConnection = (com.mysql.jdbc.Connection) driver.connect( |
| 91 | slaveUrl.toString(), slaveProperties); |
| 92 | |
| 93 | this.currentConnection = this.masterConnection; |
| 94 | } |
| 95 | |
| 96 | /* |
| 97 | * (non-Javadoc) |
| 98 | * |
| 99 | * @see java.sql.Connection#clearWarnings() |
| 100 | */ |
| 101 | public synchronized void clearWarnings() throws SQLException { |
| 102 | this.currentConnection.clearWarnings(); |
| 103 | } |
| 104 | |
| 105 | /* |
| 106 | * (non-Javadoc) |
| 107 | * |
| 108 | * @see java.sql.Connection#close() |
| 109 | */ |
| 110 | public synchronized void close() throws SQLException { |
| 111 | this.masterConnection.close(); |
| 112 | this.slavesConnection.close(); |
| 113 | } |
| 114 | |
| 115 | /* |
| 116 | * (non-Javadoc) |
| 117 | * |
| 118 | * @see java.sql.Connection#commit() |
| 119 | */ |
| 120 | public synchronized void commit() throws SQLException { |
| 121 | this.currentConnection.commit(); |
| 122 | } |
| 123 | |
| 124 | /* |
| 125 | * (non-Javadoc) |
| 126 | * |
| 127 | * @see java.sql.Connection#createStatement() |
| 128 | */ |
| 129 | public Statement createStatement() throws SQLException { |
| 130 | return this.currentConnection.createStatement(); |
| 131 | } |
| 132 | |
| 133 | /* |
| 134 | * (non-Javadoc) |
| 135 | * |
| 136 | * @see java.sql.Connection#createStatement(int, int) |
| 137 | */ |
| 138 | public synchronized Statement createStatement(int resultSetType, |
| 139 | int resultSetConcurrency) throws SQLException { |
| 140 | return this.currentConnection.createStatement(resultSetType, |
| 141 | resultSetConcurrency); |
| 142 | } |
| 143 | |
| 144 | /* |
| 145 | * (non-Javadoc) |
| 146 | * |
| 147 | * @see java.sql.Connection#createStatement(int, int, int) |
| 148 | */ |
| 149 | public synchronized Statement createStatement(int resultSetType, |
| 150 | int resultSetConcurrency, int resultSetHoldability) |
| 151 | throws SQLException { |
| 152 | return this.currentConnection.createStatement(resultSetType, |
| 153 | resultSetConcurrency, resultSetHoldability); |
| 154 | } |
| 155 | |
| 156 | /* |
| 157 | * (non-Javadoc) |
| 158 | * |
| 159 | * @see java.sql.Connection#getAutoCommit() |
| 160 | */ |
| 161 | public synchronized boolean getAutoCommit() throws SQLException { |
| 162 | return this.currentConnection.getAutoCommit(); |
| 163 | } |
| 164 | |
| 165 | /* |
| 166 | * (non-Javadoc) |
| 167 | * |
| 168 | * @see java.sql.Connection#getCatalog() |
| 169 | */ |
| 170 | public synchronized String getCatalog() throws SQLException { |
| 171 | return this.currentConnection.getCatalog(); |
| 172 | } |
| 173 | |
| 174 | public synchronized Connection getCurrentConnection() { |
| 175 | return this.currentConnection; |
| 176 | } |
| 177 | |
| 178 | /* |
| 179 | * (non-Javadoc) |
| 180 | * |
| 181 | * @see java.sql.Connection#getHoldability() |
| 182 | */ |
| 183 | public synchronized int getHoldability() throws SQLException { |
| 184 | return this.currentConnection.getHoldability(); |
| 185 | } |
| 186 | |
| 187 | public synchronized Connection getMasterConnection() { |
| 188 | return this.masterConnection; |
| 189 | } |
| 190 | |
| 191 | /* |
| 192 | * (non-Javadoc) |
| 193 | * |
| 194 | * @see java.sql.Connection#getMetaData() |
| 195 | */ |
| 196 | public synchronized DatabaseMetaData getMetaData() throws SQLException { |
| 197 | return this.currentConnection.getMetaData(); |
| 198 | } |
| 199 | |
| 200 | public synchronized Connection getSlavesConnection() { |
| 201 | return this.slavesConnection; |
| 202 | } |
| 203 | |
| 204 | /* |
| 205 | * (non-Javadoc) |
| 206 | * |
| 207 | * @see java.sql.Connection#getTransactionIsolation() |
| 208 | */ |
| 209 | public synchronized int getTransactionIsolation() throws SQLException { |
| 210 | return this.currentConnection.getTransactionIsolation(); |
| 211 | } |
| 212 | |
| 213 | /* |
| 214 | * (non-Javadoc) |
| 215 | * |
| 216 | * @see java.sql.Connection#getTypeMap() |
| 217 | */ |
| 218 | public synchronized Map getTypeMap() throws SQLException { |
| 219 | return this.currentConnection.getTypeMap(); |
| 220 | } |
| 221 | |
| 222 | /* |
| 223 | * (non-Javadoc) |
| 224 | * |
| 225 | * @see java.sql.Connection#getWarnings() |
| 226 | */ |
| 227 | public synchronized SQLWarning getWarnings() throws SQLException { |
| 228 | return this.currentConnection.getWarnings(); |
| 229 | } |
| 230 | |
| 231 | /* |
| 232 | * (non-Javadoc) |
| 233 | * |
| 234 | * @see java.sql.Connection#isClosed() |
| 235 | */ |
| 236 | public synchronized boolean isClosed() throws SQLException { |
| 237 | return this.currentConnection.isClosed(); |
| 238 | } |
| 239 | |
| 240 | /* |
| 241 | * (non-Javadoc) |
| 242 | * |
| 243 | * @see java.sql.Connection#isReadOnly() |
| 244 | */ |
| 245 | public synchronized boolean isReadOnly() throws SQLException { |
| 246 | return this.currentConnection == this.slavesConnection; |
| 247 | } |
| 248 | |
| 249 | /* |
| 250 | * (non-Javadoc) |
| 251 | * |
| 252 | * @see java.sql.Connection#nativeSQL(java.lang.String) |
| 253 | */ |
| 254 | public synchronized String nativeSQL(String sql) throws SQLException { |
| 255 | return this.currentConnection.nativeSQL(sql); |
| 256 | } |
| 257 | |
| 258 | /* |
| 259 | * (non-Javadoc) |
| 260 | * |
| 261 | * @see java.sql.Connection#prepareCall(java.lang.String) |
| 262 | */ |
| 263 | public CallableStatement prepareCall(String sql) throws SQLException { |
| 264 | return this.currentConnection.prepareCall(sql); |
| 265 | } |
| 266 | |
| 267 | /* |
| 268 | * (non-Javadoc) |
| 269 | * |
| 270 | * @see java.sql.Connection#prepareCall(java.lang.String, int, int) |
| 271 | */ |
| 272 | public synchronized CallableStatement prepareCall(String sql, |
| 273 | int resultSetType, int resultSetConcurrency) throws SQLException { |
| 274 | return this.currentConnection.prepareCall(sql, resultSetType, |
| 275 | resultSetConcurrency); |
| 276 | } |
| 277 | |
| 278 | /* |
| 279 | * (non-Javadoc) |
| 280 | * |
| 281 | * @see java.sql.Connection#prepareCall(java.lang.String, int, int, int) |
| 282 | */ |
| 283 | public synchronized CallableStatement prepareCall(String sql, |
| 284 | int resultSetType, int resultSetConcurrency, |
| 285 | int resultSetHoldability) throws SQLException { |
| 286 | return this.currentConnection.prepareCall(sql, resultSetType, |
| 287 | resultSetConcurrency, resultSetHoldability); |
| 288 | } |
| 289 | |
| 290 | /* |
| 291 | * (non-Javadoc) |
| 292 | * |
| 293 | * @see java.sql.Connection#prepareStatement(java.lang.String) |
| 294 | */ |
| 295 | public PreparedStatement prepareStatement(String sql) throws SQLException { |
| 296 | return this.currentConnection.prepareStatement(sql); |
| 297 | } |
| 298 | |
| 299 | /* |
| 300 | * (non-Javadoc) |
| 301 | * |
| 302 | * @see java.sql.Connection#prepareStatement(java.lang.String, int) |
| 303 | */ |
| 304 | public synchronized PreparedStatement prepareStatement(String sql, |
| 305 | int autoGeneratedKeys) throws SQLException { |
| 306 | return this.currentConnection.prepareStatement(sql, autoGeneratedKeys); |
| 307 | } |
| 308 | |
| 309 | /* |
| 310 | * (non-Javadoc) |
| 311 | * |
| 312 | * @see java.sql.Connection#prepareStatement(java.lang.String, int, int) |
| 313 | */ |
| 314 | public synchronized PreparedStatement prepareStatement(String sql, |
| 315 | int resultSetType, int resultSetConcurrency) throws SQLException { |
| 316 | return this.currentConnection.prepareStatement(sql, resultSetType, |
| 317 | resultSetConcurrency); |
| 318 | } |
| 319 | |
| 320 | /* |
| 321 | * (non-Javadoc) |
| 322 | * |
| 323 | * @see java.sql.Connection#prepareStatement(java.lang.String, int, int, |
| 324 | * int) |
| 325 | */ |
| 326 | public synchronized PreparedStatement prepareStatement(String sql, |
| 327 | int resultSetType, int resultSetConcurrency, |
| 328 | int resultSetHoldability) throws SQLException { |
| 329 | return this.currentConnection.prepareStatement(sql, resultSetType, |
| 330 | resultSetConcurrency, resultSetHoldability); |
| 331 | } |
| 332 | |
| 333 | /* |
| 334 | * (non-Javadoc) |
| 335 | * |
| 336 | * @see java.sql.Connection#prepareStatement(java.lang.String, int[]) |
| 337 | */ |
| 338 | public synchronized PreparedStatement prepareStatement(String sql, |
| 339 | int[] columnIndexes) throws SQLException { |
| 340 | return this.currentConnection.prepareStatement(sql, columnIndexes); |
| 341 | } |
| 342 | |
| 343 | /* |
| 344 | * (non-Javadoc) |
| 345 | * |
| 346 | * @see java.sql.Connection#prepareStatement(java.lang.String, |
| 347 | * java.lang.String[]) |
| 348 | */ |
| 349 | public synchronized PreparedStatement prepareStatement(String sql, |
| 350 | String[] columnNames) throws SQLException { |
| 351 | return this.currentConnection.prepareStatement(sql, columnNames); |
| 352 | } |
| 353 | |
| 354 | /* |
| 355 | * (non-Javadoc) |
| 356 | * |
| 357 | * @see java.sql.Connection#releaseSavepoint(java.sql.Savepoint) |
| 358 | */ |
| 359 | public synchronized void releaseSavepoint(Savepoint savepoint) |
| 360 | throws SQLException { |
| 361 | this.currentConnection.releaseSavepoint(savepoint); |
| 362 | } |
| 363 | |
| 364 | /* |
| 365 | * (non-Javadoc) |
| 366 | * |
| 367 | * @see java.sql.Connection#rollback() |
| 368 | */ |
| 369 | public synchronized void rollback() throws SQLException { |
| 370 | this.currentConnection.rollback(); |
| 371 | } |
| 372 | |
| 373 | /* |
| 374 | * (non-Javadoc) |
| 375 | * |
| 376 | * @see java.sql.Connection#rollback(java.sql.Savepoint) |
| 377 | */ |
| 378 | public synchronized void rollback(Savepoint savepoint) throws SQLException { |
| 379 | this.currentConnection.rollback(savepoint); |
| 380 | } |
| 381 | |
| 382 | /* |
| 383 | * (non-Javadoc) |
| 384 | * |
| 385 | * @see java.sql.Connection#setAutoCommit(boolean) |
| 386 | */ |
| 387 | public synchronized void setAutoCommit(boolean autoCommit) |
| 388 | throws SQLException { |
| 389 | this.currentConnection.setAutoCommit(autoCommit); |
| 390 | } |
| 391 | |
| 392 | /* |
| 393 | * (non-Javadoc) |
| 394 | * |
| 395 | * @see java.sql.Connection#setCatalog(java.lang.String) |
| 396 | */ |
| 397 | public synchronized void setCatalog(String catalog) throws SQLException { |
| 398 | this.currentConnection.setCatalog(catalog); |
| 399 | } |
| 400 | |
| 401 | /* |
| 402 | * (non-Javadoc) |
| 403 | * |
| 404 | * @see java.sql.Connection#setHoldability(int) |
| 405 | */ |
| 406 | public synchronized void setHoldability(int holdability) |
| 407 | throws SQLException { |
| 408 | this.currentConnection.setHoldability(holdability); |
| 409 | } |
| 410 | |
| 411 | /* |
| 412 | * (non-Javadoc) |
| 413 | * |
| 414 | * @see java.sql.Connection#setReadOnly(boolean) |
| 415 | */ |
| 416 | public synchronized void setReadOnly(boolean readOnly) throws SQLException { |
| 417 | if (readOnly) { |
| 418 | if (currentConnection != slavesConnection) { |
| 419 | switchToSlavesConnection(); |
| 420 | } |
| 421 | } else { |
| 422 | if (currentConnection != masterConnection) { |
| 423 | switchToMasterConnection(); |
| 424 | } |
| 425 | } |
| 426 | } |
| 427 | |
| 428 | /* |
| 429 | * (non-Javadoc) |
| 430 | * |
| 431 | * @see java.sql.Connection#setSavepoint() |
| 432 | */ |
| 433 | public synchronized Savepoint setSavepoint() throws SQLException { |
| 434 | return this.currentConnection.setSavepoint(); |
| 435 | } |
| 436 | |
| 437 | /* |
| 438 | * (non-Javadoc) |
| 439 | * |
| 440 | * @see java.sql.Connection#setSavepoint(java.lang.String) |
| 441 | */ |
| 442 | public synchronized Savepoint setSavepoint(String name) throws SQLException { |
| 443 | return this.currentConnection.setSavepoint(name); |
| 444 | } |
| 445 | |
| 446 | /* |
| 447 | * (non-Javadoc) |
| 448 | * |
| 449 | * @see java.sql.Connection#setTransactionIsolation(int) |
| 450 | */ |
| 451 | public synchronized void setTransactionIsolation(int level) |
| 452 | throws SQLException { |
| 453 | this.currentConnection.setTransactionIsolation(level); |
| 454 | } |
| 455 | |
| 456 | // For testing |
| 457 | |
| 458 | /* |
| 459 | * (non-Javadoc) |
| 460 | * |
| 461 | * @see java.sql.Connection#setTypeMap(java.util.Map) |
| 462 | */ |
| 463 | public synchronized void setTypeMap(Map arg0) throws SQLException { |
| 464 | this.currentConnection.setTypeMap(arg0); |
| 465 | } |
| 466 | |
| 467 | private synchronized void switchToMasterConnection() throws SQLException { |
| 468 | swapConnections(this.masterConnection, this.slavesConnection); |
| 469 | } |
| 470 | |
| 471 | private synchronized void switchToSlavesConnection() throws SQLException { |
| 472 | swapConnections(this.slavesConnection, this.masterConnection); |
| 473 | } |
| 474 | |
| 475 | /** |
| 476 | * Swaps current context (catalog, autocommit and txn_isolation) from |
| 477 | * sourceConnection to targetConnection, and makes targetConnection |
| 478 | * the "current" connection that will be used for queries. |
| 479 | * |
| 480 | * @param switchToConnection the connection to swap from |
| 481 | * @param switchFromConnection the connection to swap to |
| 482 | * |
| 483 | * @throws SQLException if an error occurs |
| 484 | */ |
| 485 | private synchronized void swapConnections(Connection switchToConnection, |
| 486 | Connection switchFromConnection) throws SQLException { |
| 487 | String switchFromCatalog = switchFromConnection.getCatalog(); |
| 488 | String switchToCatalog = switchToConnection.getCatalog(); |
| 489 | |
| 490 | if (switchToCatalog != null && !switchToCatalog.equals(switchFromCatalog)) { |
| 491 | switchToConnection.setCatalog(switchFromCatalog); |
| 492 | } else if (switchFromCatalog != null) { |
| 493 | switchToConnection.setCatalog(switchFromCatalog); |
| 494 | } |
| 495 | |
| 496 | boolean switchToAutoCommit = switchToConnection.getAutoCommit(); |
| 497 | boolean switchFromConnectionAutoCommit = switchFromConnection.getAutoCommit(); |
| 498 | |
| 499 | if (switchFromConnectionAutoCommit != switchToAutoCommit) { |
| 500 | switchToConnection.setAutoCommit(switchFromConnectionAutoCommit); |
| 501 | } |
| 502 | |
| 503 | int switchToIsolation = switchToConnection |
| 504 | .getTransactionIsolation(); |
| 505 | |
| 506 | int switchFromIsolation = switchFromConnection.getTransactionIsolation(); |
| 507 | |
| 508 | if (switchFromIsolation != switchToIsolation) { |
| 509 | switchToConnection |
| 510 | .setTransactionIsolation(switchFromIsolation); |
| 511 | } |
| 512 | |
| 513 | this.currentConnection = switchToConnection; |
| 514 | } |
| 515 | } |