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 */ 017 018 package org.apache.commons.pool.impl; 019 020 import java.util.ArrayList; 021 import java.util.Collection; 022 import java.util.HashMap; 023 import java.util.Iterator; 024 import java.util.LinkedList; 025 import java.util.List; 026 import java.util.Map; 027 import java.util.NoSuchElementException; 028 import java.util.Set; 029 import java.util.TreeMap; 030 import java.util.TimerTask; 031 032 import org.apache.commons.pool.BaseKeyedObjectPool; 033 import org.apache.commons.pool.KeyedObjectPool; 034 import org.apache.commons.pool.KeyedPoolableObjectFactory; 035 036 /** 037 * A configurable <code>KeyedObjectPool</code> implementation. 038 * <p> 039 * When coupled with the appropriate {@link KeyedPoolableObjectFactory}, 040 * <code>GenericKeyedObjectPool</code> provides robust pooling functionality for 041 * keyed objects. A <code>GenericKeyedObjectPool</code> can be viewed as a map 042 * of pools, keyed on the (unique) key values provided to the 043 * {@link #preparePool preparePool}, {@link #addObject addObject} or 044 * {@link #borrowObject borrowObject} methods. Each time a new key value is 045 * provided to one of these methods, a new pool is created under the given key 046 * to be managed by the containing <code>GenericKeyedObjectPool.</code> 047 * </p> 048 * <p>A <code>GenericKeyedObjectPool</code> provides a number of configurable 049 * parameters:</p> 050 * <ul> 051 * <li> 052 * {@link #setMaxActive maxActive} controls the maximum number of objects 053 * (per key) that can allocated by the pool (checked out to client threads, 054 * or idle in the pool) at one time. When non-positive, there is no limit 055 * to the number of objects per key. When {@link #setMaxActive maxActive} is 056 * reached, the keyed pool is said to be exhausted. The default setting for 057 * this parameter is 8. 058 * </li> 059 * <li> 060 * {@link #setMaxTotal maxTotal} sets a global limit on the number of objects 061 * that can be in circulation (active or idle) within the combined set of 062 * pools. When non-positive, there is no limit to the total number of 063 * objects in circulation. When {@link #setMaxTotal maxTotal} is exceeded, 064 * all keyed pools are exhausted. When <code>maxTotal</code> is set to a 065 * positive value and {@link #borrowObject borrowObject} is invoked 066 * when at the limit with no idle instances available, an attempt is made to 067 * create room by clearing the oldest 15% of the elements from the keyed 068 * pools. The default setting for this parameter is -1 (no limit). 069 * </li> 070 * <li> 071 * {@link #setMaxIdle maxIdle} controls the maximum number of objects that can 072 * sit idle in the pool (per key) at any time. When negative, there 073 * is no limit to the number of objects that may be idle per key. The 074 * default setting for this parameter is 8. 075 * </li> 076 * <li> 077 * {@link #setWhenExhaustedAction whenExhaustedAction} specifies the 078 * behavior of the {@link #borrowObject borrowObject} method when a keyed 079 * pool is exhausted: 080 * <ul> 081 * <li> 082 * When {@link #setWhenExhaustedAction whenExhaustedAction} is 083 * {@link #WHEN_EXHAUSTED_FAIL}, {@link #borrowObject borrowObject} will throw 084 * a {@link NoSuchElementException} 085 * </li> 086 * <li> 087 * When {@link #setWhenExhaustedAction whenExhaustedAction} is 088 * {@link #WHEN_EXHAUSTED_GROW}, {@link #borrowObject borrowObject} will create a new 089 * object and return it (essentially making {@link #setMaxActive maxActive} 090 * meaningless.) 091 * </li> 092 * <li> 093 * When {@link #setWhenExhaustedAction whenExhaustedAction} 094 * is {@link #WHEN_EXHAUSTED_BLOCK}, {@link #borrowObject borrowObject} will block 095 * (invoke {@link Object#wait() wait} until a new or idle object is available. 096 * If a positive {@link #setMaxWait maxWait} 097 * value is supplied, the {@link #borrowObject borrowObject} will block for at 098 * most that many milliseconds, after which a {@link NoSuchElementException} 099 * will be thrown. If {@link #setMaxWait maxWait} is non-positive, 100 * the {@link #borrowObject borrowObject} method will block indefinitely. 101 * </li> 102 * </ul> 103 * The default <code>whenExhaustedAction</code> setting is 104 * {@link #WHEN_EXHAUSTED_BLOCK}. 105 * </li> 106 * <li> 107 * When {@link #setTestOnBorrow testOnBorrow} is set, the pool will 108 * attempt to validate each object before it is returned from the 109 * {@link #borrowObject borrowObject} method. (Using the provided factory's 110 * {@link KeyedPoolableObjectFactory#validateObject validateObject} method.) 111 * Objects that fail to validate will be dropped from the pool, and a 112 * different object will be borrowed. The default setting for this parameter 113 * is <code>false.</code> 114 * </li> 115 * <li> 116 * When {@link #setTestOnReturn testOnReturn} is set, the pool will 117 * attempt to validate each object before it is returned to the pool in the 118 * {@link #returnObject returnObject} method. (Using the provided factory's 119 * {@link KeyedPoolableObjectFactory#validateObject validateObject} 120 * method.) Objects that fail to validate will be dropped from the pool. 121 * The default setting for this parameter is <code>false.</code> 122 * </li> 123 * </ul> 124 * <p> 125 * Optionally, one may configure the pool to examine and possibly evict objects 126 * as they sit idle in the pool and to ensure that a minimum number of idle 127 * objects is maintained for each key. This is performed by an 128 * "idle object eviction" thread, which runs asynchronously. Caution should be 129 * used when configuring this optional feature. Eviction runs require an 130 * exclusive synchronization lock on the pool, so if they run too frequently 131 * and / or incur excessive latency when creating, destroying or validating 132 * object instances, performance issues may result. The idle object eviction 133 * thread may be configured using the following attributes: 134 * <ul> 135 * <li> 136 * {@link #setTimeBetweenEvictionRunsMillis timeBetweenEvictionRunsMillis} 137 * indicates how long the eviction thread should sleep before "runs" of examining 138 * idle objects. When non-positive, no eviction thread will be launched. The 139 * default setting for this parameter is -1 (i.e., by default, idle object 140 * eviction is disabled). 141 * </li> 142 * <li> 143 * {@link #setMinEvictableIdleTimeMillis minEvictableIdleTimeMillis} 144 * specifies the minimum amount of time that an object may sit idle in the 145 * pool before it is eligible for eviction due to idle time. When 146 * non-positive, no object will be dropped from the pool due to idle time 147 * alone. This setting has no effect unless 148 * <code>timeBetweenEvictionRunsMillis > 0.</code> The default setting 149 * for this parameter is 30 minutes. 150 * </li> 151 * <li> 152 * {@link #setTestWhileIdle testWhileIdle} indicates whether or not idle 153 * objects should be validated using the factory's 154 * {@link KeyedPoolableObjectFactory#validateObject validateObject} method 155 * during idle object eviction runs. Objects that fail to validate will be 156 * dropped from the pool. This setting has no effect unless 157 * <code>timeBetweenEvictionRunsMillis > 0.</code> The default setting 158 * for this parameter is <code>false.</code> 159 * </li> 160 * <li> 161 * {@link #setMinIdle minIdle} sets a target value for the minimum number of 162 * idle objects (per key) that should always be available. If this parameter 163 * is set to a positive number and 164 * <code>timeBetweenEvictionRunsMillis > 0,</code> each time the idle object 165 * eviction thread runs, it will try to create enough idle instances so that 166 * there will be <code>minIdle</code> idle instances available under each 167 * key. This parameter is also used by {@link #preparePool preparePool} 168 * if <code>true</code> is provided as that method's 169 * <code>populateImmediately</code> parameter. The default setting for this 170 * parameter is 0. 171 * </li> 172 * </ul> 173 * <p> 174 * The pools can be configured to behave as LIFO queues with respect to idle 175 * objects - always returning the most recently used object from the pool, 176 * or as FIFO queues, where borrowObject always returns the oldest object 177 * in the idle object pool. 178 * <ul> 179 * <li> 180 * {@link #setLifo <i>Lifo</i>} 181 * determines whether or not the pools return idle objects in 182 * last-in-first-out order. The default setting for this parameter is 183 * <code>true.</code> 184 * </li> 185 * </ul> 186 * <p> 187 * GenericKeyedObjectPool is not usable without a {@link KeyedPoolableObjectFactory}. A 188 * non-<code>null</code> factory must be provided either as a constructor argument 189 * or via a call to {@link #setFactory setFactory} before the pool is used. 190 * </p> 191 * <p> 192 * Implementation note: To prevent possible deadlocks, care has been taken to 193 * ensure that no call to a factory method will occur within a synchronization 194 * block. See POOL-125 and DBCP-44 for more information. 195 * </p> 196 * @see GenericObjectPool 197 * @author Rodney Waldhoff 198 * @author Dirk Verbeeck 199 * @author Sandy McArthur 200 * @version $Revision: 791907 $ $Date: 2009-07-07 12:56:33 -0400 (Tue, 07 Jul 2009) $ 201 * @since Pool 1.0 202 */ 203 public class GenericKeyedObjectPool extends BaseKeyedObjectPool implements KeyedObjectPool { 204 205 //--- public constants ------------------------------------------- 206 207 /** 208 * A "when exhausted action" type indicating that when the pool is 209 * exhausted (i.e., the maximum number of active objects has 210 * been reached), the {@link #borrowObject} 211 * method should fail, throwing a {@link NoSuchElementException}. 212 * @see #WHEN_EXHAUSTED_BLOCK 213 * @see #WHEN_EXHAUSTED_GROW 214 * @see #setWhenExhaustedAction 215 */ 216 public static final byte WHEN_EXHAUSTED_FAIL = 0; 217 218 /** 219 * A "when exhausted action" type indicating that when the pool 220 * is exhausted (i.e., the maximum number 221 * of active objects has been reached), the {@link #borrowObject} 222 * method should block until a new object is available, or the 223 * {@link #getMaxWait maximum wait time} has been reached. 224 * @see #WHEN_EXHAUSTED_FAIL 225 * @see #WHEN_EXHAUSTED_GROW 226 * @see #setMaxWait 227 * @see #getMaxWait 228 * @see #setWhenExhaustedAction 229 */ 230 public static final byte WHEN_EXHAUSTED_BLOCK = 1; 231 232 /** 233 * A "when exhausted action" type indicating that when the pool is 234 * exhausted (i.e., the maximum number 235 * of active objects has been reached), the {@link #borrowObject} 236 * method should simply create a new object anyway. 237 * @see #WHEN_EXHAUSTED_FAIL 238 * @see #WHEN_EXHAUSTED_GROW 239 * @see #setWhenExhaustedAction 240 */ 241 public static final byte WHEN_EXHAUSTED_GROW = 2; 242 243 /** 244 * The default cap on the number of idle instances (per key) in the pool. 245 * @see #getMaxIdle 246 * @see #setMaxIdle 247 */ 248 public static final int DEFAULT_MAX_IDLE = 8; 249 250 /** 251 * The default cap on the total number of active instances (per key) 252 * from the pool. 253 * @see #getMaxActive 254 * @see #setMaxActive 255 */ 256 public static final int DEFAULT_MAX_ACTIVE = 8; 257 258 /** 259 * The default cap on the the overall maximum number of objects that can 260 * exist at one time. 261 * @see #getMaxTotal 262 * @see #setMaxTotal 263 */ 264 public static final int DEFAULT_MAX_TOTAL = -1; 265 266 /** 267 * The default "when exhausted action" for the pool. 268 * @see #WHEN_EXHAUSTED_BLOCK 269 * @see #WHEN_EXHAUSTED_FAIL 270 * @see #WHEN_EXHAUSTED_GROW 271 * @see #setWhenExhaustedAction 272 */ 273 public static final byte DEFAULT_WHEN_EXHAUSTED_ACTION = WHEN_EXHAUSTED_BLOCK; 274 275 /** 276 * The default maximum amount of time (in milliseconds) the 277 * {@link #borrowObject} method should block before throwing 278 * an exception when the pool is exhausted and the 279 * {@link #getWhenExhaustedAction "when exhausted" action} is 280 * {@link #WHEN_EXHAUSTED_BLOCK}. 281 * @see #getMaxWait 282 * @see #setMaxWait 283 */ 284 public static final long DEFAULT_MAX_WAIT = -1L; 285 286 /** 287 * The default "test on borrow" value. 288 * @see #getTestOnBorrow 289 * @see #setTestOnBorrow 290 */ 291 public static final boolean DEFAULT_TEST_ON_BORROW = false; 292 293 /** 294 * The default "test on return" value. 295 * @see #getTestOnReturn 296 * @see #setTestOnReturn 297 */ 298 public static final boolean DEFAULT_TEST_ON_RETURN = false; 299 300 /** 301 * The default "test while idle" value. 302 * @see #getTestWhileIdle 303 * @see #setTestWhileIdle 304 * @see #getTimeBetweenEvictionRunsMillis 305 * @see #setTimeBetweenEvictionRunsMillis 306 */ 307 public static final boolean DEFAULT_TEST_WHILE_IDLE = false; 308 309 /** 310 * The default "time between eviction runs" value. 311 * @see #getTimeBetweenEvictionRunsMillis 312 * @see #setTimeBetweenEvictionRunsMillis 313 */ 314 public static final long DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS = -1L; 315 316 /** 317 * The default number of objects to examine per run in the 318 * idle object evictor. 319 * @see #getNumTestsPerEvictionRun 320 * @see #setNumTestsPerEvictionRun 321 * @see #getTimeBetweenEvictionRunsMillis 322 * @see #setTimeBetweenEvictionRunsMillis 323 */ 324 public static final int DEFAULT_NUM_TESTS_PER_EVICTION_RUN = 3; 325 326 /** 327 * The default value for {@link #getMinEvictableIdleTimeMillis}. 328 * @see #getMinEvictableIdleTimeMillis 329 * @see #setMinEvictableIdleTimeMillis 330 */ 331 public static final long DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS = 1000L * 60L * 30L; 332 333 /** 334 * The default minimum level of idle objects in the pool. 335 * @since Pool 1.3 336 * @see #setMinIdle 337 * @see #getMinIdle 338 */ 339 public static final int DEFAULT_MIN_IDLE = 0; 340 341 /** 342 * The default LIFO status. True means that borrowObject returns the 343 * most recently used ("last in") idle object in a pool (if there are 344 * idle instances available). False means that pools behave as FIFO 345 * queues - objects are taken from idle object pools in the order that 346 * they are returned. 347 * @see #setLifo 348 */ 349 public static final boolean DEFAULT_LIFO = true; 350 351 //--- constructors ----------------------------------------------- 352 353 /** 354 * Create a new <code>GenericKeyedObjectPool</code> with no factory. 355 * 356 * @see #GenericKeyedObjectPool(KeyedPoolableObjectFactory) 357 * @see #setFactory(KeyedPoolableObjectFactory) 358 */ 359 public GenericKeyedObjectPool() { 360 this(null, DEFAULT_MAX_ACTIVE, DEFAULT_WHEN_EXHAUSTED_ACTION, DEFAULT_MAX_WAIT, DEFAULT_MAX_IDLE, 361 DEFAULT_TEST_ON_BORROW, DEFAULT_TEST_ON_RETURN, DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS, 362 DEFAULT_NUM_TESTS_PER_EVICTION_RUN, DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS, DEFAULT_TEST_WHILE_IDLE); 363 } 364 365 /** 366 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 367 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy 368 * objects if not <code>null</code> 369 */ 370 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory) { 371 this(factory, DEFAULT_MAX_ACTIVE, DEFAULT_WHEN_EXHAUSTED_ACTION, DEFAULT_MAX_WAIT, DEFAULT_MAX_IDLE, 372 DEFAULT_TEST_ON_BORROW, DEFAULT_TEST_ON_RETURN, DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS, 373 DEFAULT_NUM_TESTS_PER_EVICTION_RUN, DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS, DEFAULT_TEST_WHILE_IDLE); 374 } 375 376 /** 377 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 378 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 379 * if not <code>null</code> 380 * @param config a non-<code>null</code> {@link GenericKeyedObjectPool.Config} describing the configuration 381 */ 382 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, GenericKeyedObjectPool.Config config) { 383 this(factory, config.maxActive, config.whenExhaustedAction, config.maxWait, config.maxIdle, config.maxTotal, 384 config.minIdle, config.testOnBorrow, config.testOnReturn, config.timeBetweenEvictionRunsMillis, 385 config.numTestsPerEvictionRun, config.minEvictableIdleTimeMillis, config.testWhileIdle, config.lifo); 386 } 387 388 /** 389 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 390 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 391 * if not <code>null</code> 392 * @param maxActive the maximum number of objects that can be borrowed from me at one time (see {@link #setMaxActive}) 393 */ 394 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, int maxActive) { 395 this(factory,maxActive, DEFAULT_WHEN_EXHAUSTED_ACTION, DEFAULT_MAX_WAIT, DEFAULT_MAX_IDLE, 396 DEFAULT_TEST_ON_BORROW, DEFAULT_TEST_ON_RETURN, DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS, 397 DEFAULT_NUM_TESTS_PER_EVICTION_RUN, DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS, DEFAULT_TEST_WHILE_IDLE); 398 } 399 400 /** 401 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 402 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 403 * if not <code>null</code> 404 * @param maxActive the maximum number of objects that can be borrowed from me at one time (see {@link #setMaxActive}) 405 * @param whenExhaustedAction the action to take when the pool is exhausted (see {@link #setWhenExhaustedAction}) 406 * @param maxWait the maximum amount of time to wait for an idle object when the pool is exhausted and 407 * <code>whenExhaustedAction</code> is {@link #WHEN_EXHAUSTED_BLOCK} (otherwise ignored) (see {@link #setMaxWait}) 408 */ 409 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, 410 long maxWait) { 411 this(factory, maxActive, whenExhaustedAction, maxWait, DEFAULT_MAX_IDLE, DEFAULT_TEST_ON_BORROW, 412 DEFAULT_TEST_ON_RETURN, DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS, DEFAULT_NUM_TESTS_PER_EVICTION_RUN, 413 DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS, DEFAULT_TEST_WHILE_IDLE); 414 } 415 416 /** 417 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 418 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 419 * if not <code>null</code> 420 * @param maxActive the maximum number of objects that can be borrowed from me at one time (see {@link #setMaxActive}) 421 * @param maxWait the maximum amount of time to wait for an idle object when the pool is exhausted and 422 * <code>whenExhaustedAction</code> is {@link #WHEN_EXHAUSTED_BLOCK} (otherwise ignored) (see {@link #setMaxWait}) 423 * @param whenExhaustedAction the action to take when the pool is exhausted (see {@link #setWhenExhaustedAction}) 424 * @param testOnBorrow whether or not to validate objects before they are returned by the {@link #borrowObject} 425 * method (see {@link #setTestOnBorrow}) 426 * @param testOnReturn whether or not to validate objects after they are returned to the {@link #returnObject} 427 * method (see {@link #setTestOnReturn}) 428 */ 429 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, 430 long maxWait, boolean testOnBorrow, boolean testOnReturn) { 431 this(factory, maxActive, whenExhaustedAction, maxWait, DEFAULT_MAX_IDLE,testOnBorrow,testOnReturn, 432 DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS, DEFAULT_NUM_TESTS_PER_EVICTION_RUN, 433 DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS, DEFAULT_TEST_WHILE_IDLE); 434 } 435 436 /** 437 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 438 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 439 * if not <code>null</code> 440 * @param maxActive the maximum number of objects that can be borrowed from me at one time 441 * (see {@link #setMaxActive}) 442 * @param whenExhaustedAction the action to take when the pool is exhausted (see {@link #setWhenExhaustedAction}) 443 * @param maxWait the maximum amount of time to wait for an idle object when the pool is exhausted and 444 * <code>whenExhaustedAction</code> is {@link #WHEN_EXHAUSTED_BLOCK} (otherwise ignored) (see {@link #setMaxWait}) 445 * @param maxIdle the maximum number of idle objects in my pool (see {@link #setMaxIdle}) 446 */ 447 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, 448 long maxWait, int maxIdle) { 449 this(factory, maxActive, whenExhaustedAction, maxWait, maxIdle, DEFAULT_TEST_ON_BORROW, DEFAULT_TEST_ON_RETURN, 450 DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS, DEFAULT_NUM_TESTS_PER_EVICTION_RUN, 451 DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS, DEFAULT_TEST_WHILE_IDLE); 452 } 453 454 /** 455 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 456 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 457 * if not <code>null</code> 458 * @param maxActive the maximum number of objects that can be borrowed from me at one time 459 * (see {@link #setMaxActive}) 460 * @param whenExhaustedAction the action to take when the pool is exhausted (see {@link #setWhenExhaustedAction}) 461 * @param maxWait the maximum amount of time to wait for an idle object when the pool is exhausted and 462 * <code>whenExhaustedAction</code> is {@link #WHEN_EXHAUSTED_BLOCK} (otherwise ignored) (see {@link #getMaxWait}) 463 * @param maxIdle the maximum number of idle objects in my pool (see {@link #setMaxIdle}) 464 * @param testOnBorrow whether or not to validate objects before they are returned by the {@link #borrowObject} 465 * method (see {@link #setTestOnBorrow}) 466 * @param testOnReturn whether or not to validate objects after they are returned to the {@link #returnObject} 467 * method (see {@link #setTestOnReturn}) 468 */ 469 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, 470 long maxWait, int maxIdle, boolean testOnBorrow, boolean testOnReturn) { 471 this(factory, maxActive, whenExhaustedAction, maxWait, maxIdle, testOnBorrow, testOnReturn, 472 DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS, DEFAULT_NUM_TESTS_PER_EVICTION_RUN, 473 DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS, DEFAULT_TEST_WHILE_IDLE); 474 } 475 476 /** 477 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 478 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 479 * if not <code>null</code> 480 * @param maxActive the maximum number of objects that can be borrowed from me at one time 481 * (see {@link #setMaxActive}) 482 * @param whenExhaustedAction the action to take when the pool is exhausted 483 * (see {@link #setWhenExhaustedAction}) 484 * @param maxWait the maximum amount of time to wait for an idle object when the pool is exhausted and 485 * <code>whenExhaustedAction</code> is {@link #WHEN_EXHAUSTED_BLOCK} (otherwise ignored) (see {@link #setMaxWait}) 486 * @param maxIdle the maximum number of idle objects in my pool (see {@link #setMaxIdle}) 487 * @param testOnBorrow whether or not to validate objects before they are returned by the {@link #borrowObject} 488 * method (see {@link #setTestOnBorrow}) 489 * @param testOnReturn whether or not to validate objects after they are returned to the {@link #returnObject} 490 * method (see {@link #setTestOnReturn}) 491 * @param timeBetweenEvictionRunsMillis the amount of time (in milliseconds) to sleep between examining idle 492 * objects for eviction (see {@link #setTimeBetweenEvictionRunsMillis}) 493 * @param numTestsPerEvictionRun the number of idle objects to examine per run within the idle object eviction 494 * thread (if any) (see {@link #setNumTestsPerEvictionRun}) 495 * @param minEvictableIdleTimeMillis the minimum number of milliseconds an object can sit idle in the pool before 496 * it is eligible for eviction (see {@link #setMinEvictableIdleTimeMillis}) 497 * @param testWhileIdle whether or not to validate objects in the idle object eviction thread, if any 498 * (see {@link #setTestWhileIdle}) 499 */ 500 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, 501 long maxWait, int maxIdle, boolean testOnBorrow, boolean testOnReturn, long timeBetweenEvictionRunsMillis, 502 int numTestsPerEvictionRun, long minEvictableIdleTimeMillis, boolean testWhileIdle) { 503 this(factory, maxActive, whenExhaustedAction, maxWait, maxIdle, GenericKeyedObjectPool.DEFAULT_MAX_TOTAL, 504 testOnBorrow, testOnReturn, timeBetweenEvictionRunsMillis, numTestsPerEvictionRun, 505 minEvictableIdleTimeMillis, testWhileIdle); 506 } 507 508 /** 509 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 510 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 511 * if not <code>null</code> 512 * @param maxActive the maximum number of objects that can be borrowed from me at one time 513 * (see {@link #setMaxActive}) 514 * @param whenExhaustedAction the action to take when the pool is exhausted (see {@link #setWhenExhaustedAction}) 515 * @param maxWait the maximum amount of time to wait for an idle object when the pool is exhausted and 516 * <code>whenExhaustedAction</code> is {@link #WHEN_EXHAUSTED_BLOCK} (otherwise ignored) (see {@link #setMaxWait}) 517 * @param maxIdle the maximum number of idle objects in my pool (see {@link #setMaxIdle}) 518 * @param maxTotal the maximum number of objects that can exists at one time (see {@link #setMaxTotal}) 519 * @param testOnBorrow whether or not to validate objects before they are returned by the {@link #borrowObject} 520 * method (see {@link #setTestOnBorrow}) 521 * @param testOnReturn whether or not to validate objects after they are returned to the {@link #returnObject} 522 * method (see {@link #setTestOnReturn}) 523 * @param timeBetweenEvictionRunsMillis the amount of time (in milliseconds) to sleep between examining idle 524 * objects for eviction (see {@link #setTimeBetweenEvictionRunsMillis}) 525 * @param numTestsPerEvictionRun the number of idle objects to examine per run within the idle object eviction 526 * thread (if any) (see {@link #setNumTestsPerEvictionRun}) 527 * @param minEvictableIdleTimeMillis the minimum number of milliseconds an object can sit idle in the pool 528 * before it is eligible for eviction (see {@link #setMinEvictableIdleTimeMillis}) 529 * @param testWhileIdle whether or not to validate objects in the idle object eviction thread, if any 530 * (see {@link #setTestWhileIdle}) 531 */ 532 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, 533 long maxWait, int maxIdle, int maxTotal, boolean testOnBorrow, boolean testOnReturn, 534 long timeBetweenEvictionRunsMillis, int numTestsPerEvictionRun, long minEvictableIdleTimeMillis, 535 boolean testWhileIdle) { 536 this(factory, maxActive, whenExhaustedAction, maxWait, maxIdle, maxTotal, 537 GenericKeyedObjectPool.DEFAULT_MIN_IDLE, testOnBorrow, testOnReturn, timeBetweenEvictionRunsMillis, 538 numTestsPerEvictionRun, minEvictableIdleTimeMillis, testWhileIdle); 539 } 540 541 /** 542 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 543 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 544 * if not <code>null</code> 545 * @param maxActive the maximum number of objects that can be borrowed at one time (see {@link #setMaxActive}) 546 * @param whenExhaustedAction the action to take when the pool is exhausted (see {@link #setWhenExhaustedAction}) 547 * @param maxWait the maximum amount of time to wait for an idle object when the pool is exhausted and 548 * <code>whenExhaustedAction</code> is {@link #WHEN_EXHAUSTED_BLOCK} (otherwise ignored) (see {@link #setMaxWait}) 549 * @param maxIdle the maximum number of idle objects in my pool (see {@link #setMaxIdle}) 550 * @param maxTotal the maximum number of objects that can exists at one time (see {@link #setMaxTotal}) 551 * @param minIdle the minimum number of idle objects to have in the pool at any one time (see {@link #setMinIdle}) 552 * @param testOnBorrow whether or not to validate objects before they are returned by the {@link #borrowObject} 553 * method (see {@link #setTestOnBorrow}) 554 * @param testOnReturn whether or not to validate objects after they are returned to the {@link #returnObject} 555 * method (see {@link #setTestOnReturn}) 556 * @param timeBetweenEvictionRunsMillis the amount of time (in milliseconds) to sleep between examining idle 557 * objects 558 * for eviction (see {@link #setTimeBetweenEvictionRunsMillis}) 559 * @param numTestsPerEvictionRun the number of idle objects to examine per run within the idle object eviction 560 * thread (if any) (see {@link #setNumTestsPerEvictionRun}) 561 * @param minEvictableIdleTimeMillis the minimum number of milliseconds an object can sit idle in the pool before 562 * it is eligible for eviction (see {@link #setMinEvictableIdleTimeMillis}) 563 * @param testWhileIdle whether or not to validate objects in the idle object eviction thread, if any 564 * (see {@link #setTestWhileIdle}) 565 * @since Pool 1.3 566 */ 567 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, 568 long maxWait, int maxIdle, int maxTotal, int minIdle, boolean testOnBorrow, boolean testOnReturn, 569 long timeBetweenEvictionRunsMillis, int numTestsPerEvictionRun, long minEvictableIdleTimeMillis, 570 boolean testWhileIdle) { 571 this(factory, maxActive, whenExhaustedAction, maxWait, maxIdle, maxTotal, minIdle, testOnBorrow, testOnReturn, 572 timeBetweenEvictionRunsMillis, numTestsPerEvictionRun, minEvictableIdleTimeMillis, testWhileIdle, 573 DEFAULT_LIFO); 574 } 575 576 /** 577 * Create a new <code>GenericKeyedObjectPool</code> using the specified values. 578 * @param factory the <code>KeyedPoolableObjectFactory</code> to use to create, validate, and destroy objects 579 * if not <code>null</code> 580 * @param maxActive the maximum number of objects that can be borrowed at one time 581 * (see {@link #setMaxActive}) 582 * @param whenExhaustedAction the action to take when the pool is exhausted (see {@link #setWhenExhaustedAction}) 583 * @param maxWait the maximum amount of time to wait for an idle object when the pool is exhausted and 584 * <code>whenExhaustedAction</code> is {@link #WHEN_EXHAUSTED_BLOCK} (otherwise ignored) (see {@link #setMaxWait}) 585 * @param maxIdle the maximum number of idle objects in my pool (see {@link #setMaxIdle}) 586 * @param maxTotal the maximum number of objects that can exists at one time (see {@link #setMaxTotal}) 587 * @param minIdle the minimum number of idle objects to have in the pool at any one time (see {@link #setMinIdle}) 588 * @param testOnBorrow whether or not to validate objects before they are returned by the {@link #borrowObject} 589 * method (see {@link #setTestOnBorrow}) 590 * @param testOnReturn whether or not to validate objects after they are returned to the {@link #returnObject} 591 * method (see {@link #setTestOnReturn}) 592 * @param timeBetweenEvictionRunsMillis the amount of time (in milliseconds) to sleep between examining idle 593 * objects for eviction (see {@link #setTimeBetweenEvictionRunsMillis}) 594 * @param numTestsPerEvictionRun the number of idle objects to examine per run within the idle object eviction 595 * thread (if any) (see {@link #setNumTestsPerEvictionRun}) 596 * @param minEvictableIdleTimeMillis the minimum number of milliseconds an object can sit idle in the pool before 597 * it is eligible for eviction (see {@link #setMinEvictableIdleTimeMillis}) 598 * @param testWhileIdle whether or not to validate objects in the idle object eviction thread, if any 599 * (see {@link #setTestWhileIdle}) 600 * @param lifo whether or not the pools behave as LIFO (last in first out) queues (see {@link #setLifo}) 601 * @since Pool 1.4 602 */ 603 public GenericKeyedObjectPool(KeyedPoolableObjectFactory factory, int maxActive, byte whenExhaustedAction, 604 long maxWait, int maxIdle, int maxTotal, int minIdle, boolean testOnBorrow, boolean testOnReturn, 605 long timeBetweenEvictionRunsMillis, int numTestsPerEvictionRun, long minEvictableIdleTimeMillis, 606 boolean testWhileIdle, boolean lifo) { 607 _factory = factory; 608 _maxActive = maxActive; 609 _lifo = lifo; 610 switch (whenExhaustedAction) { 611 case WHEN_EXHAUSTED_BLOCK: 612 case WHEN_EXHAUSTED_FAIL: 613 case WHEN_EXHAUSTED_GROW: 614 _whenExhaustedAction = whenExhaustedAction; 615 break; 616 default: 617 throw new IllegalArgumentException("whenExhaustedAction " + whenExhaustedAction + " not recognized."); 618 } 619 _maxWait = maxWait; 620 _maxIdle = maxIdle; 621 _maxTotal = maxTotal; 622 _minIdle = minIdle; 623 _testOnBorrow = testOnBorrow; 624 _testOnReturn = testOnReturn; 625 _timeBetweenEvictionRunsMillis = timeBetweenEvictionRunsMillis; 626 _numTestsPerEvictionRun = numTestsPerEvictionRun; 627 _minEvictableIdleTimeMillis = minEvictableIdleTimeMillis; 628 _testWhileIdle = testWhileIdle; 629 630 _poolMap = new HashMap(); 631 _poolList = new CursorableLinkedList(); 632 633 startEvictor(_timeBetweenEvictionRunsMillis); 634 } 635 636 //--- public methods --------------------------------------------- 637 638 //--- configuration methods -------------------------------------- 639 640 /** 641 * Returns the cap on the number of object instances allocated by the pool 642 * (checked out or idle), per key. 643 * A negative value indicates no limit. 644 * 645 * @return the cap on the number of active instances per key. 646 * @see #setMaxActive 647 */ 648 public synchronized int getMaxActive() { 649 return _maxActive; 650 } 651 652 /** 653 * Sets the cap on the number of object instances managed by the pool per key. 654 * @param maxActive The cap on the number of object instances per key. 655 * Use a negative value for no limit. 656 * 657 * @see #getMaxActive 658 */ 659 public synchronized void setMaxActive(int maxActive) { 660 _maxActive = maxActive; 661 allocate(); 662 } 663 664 /** 665 * Returns the overall maximum number of objects (across pools) that can 666 * exist at one time. A negative value indicates no limit. 667 * @return the maximum number of instances in circulation at one time. 668 * @see #setMaxTotal 669 */ 670 public synchronized int getMaxTotal() { 671 return _maxTotal; 672 } 673 674 /** 675 * Sets the cap on the total number of instances from all pools combined. 676 * When <code>maxTotal</code> is set to a 677 * positive value and {@link #borrowObject borrowObject} is invoked 678 * when at the limit with no idle instances available, an attempt is made to 679 * create room by clearing the oldest 15% of the elements from the keyed 680 * pools. 681 * 682 * @param maxTotal The cap on the total number of instances across pools. 683 * Use a negative value for no limit. 684 * @see #getMaxTotal 685 */ 686 public synchronized void setMaxTotal(int maxTotal) { 687 _maxTotal = maxTotal; 688 allocate(); 689 } 690 691 /** 692 * Returns the action to take when the {@link #borrowObject} method 693 * is invoked when the pool is exhausted (the maximum number 694 * of "active" objects has been reached). 695 * 696 * @return one of {@link #WHEN_EXHAUSTED_BLOCK}, 697 * {@link #WHEN_EXHAUSTED_FAIL} or {@link #WHEN_EXHAUSTED_GROW} 698 * @see #setWhenExhaustedAction 699 */ 700 public synchronized byte getWhenExhaustedAction() { 701 return _whenExhaustedAction; 702 } 703 704 /** 705 * Sets the action to take when the {@link #borrowObject} method 706 * is invoked when the pool is exhausted (the maximum number 707 * of "active" objects has been reached). 708 * 709 * @param whenExhaustedAction the action code, which must be one of 710 * {@link #WHEN_EXHAUSTED_BLOCK}, {@link #WHEN_EXHAUSTED_FAIL}, 711 * or {@link #WHEN_EXHAUSTED_GROW} 712 * @see #getWhenExhaustedAction 713 */ 714 public synchronized void setWhenExhaustedAction(byte whenExhaustedAction) { 715 switch(whenExhaustedAction) { 716 case WHEN_EXHAUSTED_BLOCK: 717 case WHEN_EXHAUSTED_FAIL: 718 case WHEN_EXHAUSTED_GROW: 719 _whenExhaustedAction = whenExhaustedAction; 720 allocate(); 721 break; 722 default: 723 throw new IllegalArgumentException("whenExhaustedAction " + whenExhaustedAction + " not recognized."); 724 } 725 } 726 727 728 /** 729 * Returns the maximum amount of time (in milliseconds) the 730 * {@link #borrowObject} method should block before throwing 731 * an exception when the pool is exhausted and the 732 * {@link #setWhenExhaustedAction "when exhausted" action} is 733 * {@link #WHEN_EXHAUSTED_BLOCK}. 734 * 735 * When less than or equal to 0, the {@link #borrowObject} method 736 * may block indefinitely. 737 * 738 * @return the maximum number of milliseconds borrowObject will block. 739 * @see #setMaxWait 740 * @see #setWhenExhaustedAction 741 * @see #WHEN_EXHAUSTED_BLOCK 742 */ 743 public synchronized long getMaxWait() { 744 return _maxWait; 745 } 746 747 /** 748 * Sets the maximum amount of time (in milliseconds) the 749 * {@link #borrowObject} method should block before throwing 750 * an exception when the pool is exhausted and the 751 * {@link #setWhenExhaustedAction "when exhausted" action} is 752 * {@link #WHEN_EXHAUSTED_BLOCK}. 753 * 754 * When less than or equal to 0, the {@link #borrowObject} method 755 * may block indefinitely. 756 * 757 * @param maxWait the maximum number of milliseconds borrowObject will block or negative for indefinitely. 758 * @see #getMaxWait 759 * @see #setWhenExhaustedAction 760 * @see #WHEN_EXHAUSTED_BLOCK 761 */ 762 public synchronized void setMaxWait(long maxWait) { 763 _maxWait = maxWait; 764 } 765 766 /** 767 * Returns the cap on the number of "idle" instances per key. 768 * @return the maximum number of "idle" instances that can be held 769 * in a given keyed pool. 770 * @see #setMaxIdle 771 */ 772 public synchronized int getMaxIdle() { 773 return _maxIdle; 774 } 775 776 /** 777 * Sets the cap on the number of "idle" instances in the pool. 778 * If maxIdle is set too low on heavily loaded systems it is possible you 779 * will see objects being destroyed and almost immediately new objects 780 * being created. This is a result of the active threads momentarily 781 * returning objects faster than they are requesting them them, causing the 782 * number of idle objects to rise above maxIdle. The best value for maxIdle 783 * for heavily loaded system will vary but the default is a good starting 784 * point. 785 * @param maxIdle the maximum number of "idle" instances that can be held 786 * in a given keyed pool. Use a negative value for no limit. 787 * @see #getMaxIdle 788 * @see #DEFAULT_MAX_IDLE 789 */ 790 public synchronized void setMaxIdle(int maxIdle) { 791 _maxIdle = maxIdle; 792 allocate(); 793 } 794 795 /** 796 * Sets the minimum number of idle objects to maintain in each of the keyed 797 * pools. This setting has no effect unless 798 * <code>timeBetweenEvictionRunsMillis > 0</code> and attempts to ensure 799 * that each pool has the required minimum number of instances are only 800 * made during idle object eviction runs. 801 * @param poolSize - The minimum size of the each keyed pool 802 * @since Pool 1.3 803 * @see #getMinIdle 804 * @see #setTimeBetweenEvictionRunsMillis 805 */ 806 public synchronized void setMinIdle(int poolSize) { 807 _minIdle = poolSize; 808 } 809 810 /** 811 * Returns the minimum number of idle objects to maintain in each of the keyed 812 * pools. This setting has no effect unless 813 * <code>timeBetweenEvictionRunsMillis > 0</code> and attempts to ensure 814 * that each pool has the required minimum number of instances are only 815 * made during idle object eviction runs. 816 * @return minimum size of the each keyed pool 817 * @since Pool 1.3 818 * @see #setTimeBetweenEvictionRunsMillis 819 */ 820 public synchronized int getMinIdle() { 821 return _minIdle; 822 } 823 824 /** 825 * When <code>true</code>, objects will be 826 * {@link org.apache.commons.pool.PoolableObjectFactory#validateObject validated} 827 * before being returned by the {@link #borrowObject} 828 * method. If the object fails to validate, 829 * it will be dropped from the pool, and we will attempt 830 * to borrow another. 831 * 832 * @return <code>true</code> if objects are validated before being borrowed. 833 * @see #setTestOnBorrow 834 */ 835 public boolean getTestOnBorrow() { 836 return _testOnBorrow; 837 } 838 839 /** 840 * When <code>true</code>, objects will be 841 * {@link org.apache.commons.pool.PoolableObjectFactory#validateObject validated} 842 * before being returned by the {@link #borrowObject} 843 * method. If the object fails to validate, 844 * it will be dropped from the pool, and we will attempt 845 * to borrow another. 846 * 847 * @param testOnBorrow whether object should be validated before being returned by borrowObject. 848 * @see #getTestOnBorrow 849 */ 850 public void setTestOnBorrow(boolean testOnBorrow) { 851 _testOnBorrow = testOnBorrow; 852 } 853 854 /** 855 * When <code>true</code>, objects will be 856 * {@link org.apache.commons.pool.PoolableObjectFactory#validateObject validated} 857 * before being returned to the pool within the 858 * {@link #returnObject}. 859 * 860 * @return <code>true</code> when objects will be validated before being returned. 861 * @see #setTestOnReturn 862 */ 863 public boolean getTestOnReturn() { 864 return _testOnReturn; 865 } 866 867 /** 868 * When <code>true</code>, objects will be 869 * {@link org.apache.commons.pool.PoolableObjectFactory#validateObject validated} 870 * before being returned to the pool within the 871 * {@link #returnObject}. 872 * 873 * @param testOnReturn <code>true</code> so objects will be validated before being returned. 874 * @see #getTestOnReturn 875 */ 876 public void setTestOnReturn(boolean testOnReturn) { 877 _testOnReturn = testOnReturn; 878 } 879 880 /** 881 * Returns the number of milliseconds to sleep between runs of the 882 * idle object evictor thread. 883 * When non-positive, no idle object evictor thread will be 884 * run. 885 * 886 * @return milliseconds to sleep between evictor runs. 887 * @see #setTimeBetweenEvictionRunsMillis 888 */ 889 public synchronized long getTimeBetweenEvictionRunsMillis() { 890 return _timeBetweenEvictionRunsMillis; 891 } 892 893 /** 894 * Sets the number of milliseconds to sleep between runs of the 895 * idle object evictor thread. 896 * When non-positive, no idle object evictor thread will be 897 * run. 898 * 899 * @param timeBetweenEvictionRunsMillis milliseconds to sleep between evictor runs. 900 * @see #getTimeBetweenEvictionRunsMillis 901 */ 902 public synchronized void setTimeBetweenEvictionRunsMillis(long timeBetweenEvictionRunsMillis) { 903 _timeBetweenEvictionRunsMillis = timeBetweenEvictionRunsMillis; 904 startEvictor(_timeBetweenEvictionRunsMillis); 905 } 906 907 /** 908 * Returns the max number of objects to examine during each run of the 909 * idle object evictor thread (if any). 910 * 911 * @return number of objects to examine each eviction run. 912 * @see #setNumTestsPerEvictionRun 913 * @see #setTimeBetweenEvictionRunsMillis 914 */ 915 public synchronized int getNumTestsPerEvictionRun() { 916 return _numTestsPerEvictionRun; 917 } 918 919 /** 920 * Sets the max number of objects to examine during each run of the 921 * idle object evictor thread (if any). 922 * <p> 923 * When a negative value is supplied, 924 * <code>ceil({@link #getNumIdle()})/abs({@link #getNumTestsPerEvictionRun})</code> 925 * tests will be run. I.e., when the value is <code>-n</code>, roughly one <code>n</code>th of the 926 * idle objects will be tested per run. When the value is positive, the number of tests 927 * actually performed in each run will be the minimum of this value and the number of instances 928 * idle in the pools. 929 * 930 * @param numTestsPerEvictionRun number of objects to examine each eviction run. 931 * @see #setNumTestsPerEvictionRun 932 * @see #setTimeBetweenEvictionRunsMillis 933 */ 934 public synchronized void setNumTestsPerEvictionRun(int numTestsPerEvictionRun) { 935 _numTestsPerEvictionRun = numTestsPerEvictionRun; 936 } 937 938 /** 939 * Returns the minimum amount of time an object may sit idle in the pool 940 * before it is eligible for eviction by the idle object evictor 941 * (if any). 942 * 943 * @return minimum amount of time an object may sit idle in the pool before it is eligible for eviction. 944 * @see #setMinEvictableIdleTimeMillis 945 * @see #setTimeBetweenEvictionRunsMillis 946 */ 947 public synchronized long getMinEvictableIdleTimeMillis() { 948 return _minEvictableIdleTimeMillis; 949 } 950 951 /** 952 * Sets the minimum amount of time an object may sit idle in the pool 953 * before it is eligible for eviction by the idle object evictor 954 * (if any). 955 * When non-positive, no objects will be evicted from the pool 956 * due to idle time alone. 957 * 958 * @param minEvictableIdleTimeMillis minimum amount of time an object may sit idle in the pool before 959 * it is eligible for eviction. 960 * @see #getMinEvictableIdleTimeMillis 961 * @see #setTimeBetweenEvictionRunsMillis 962 */ 963 public synchronized void setMinEvictableIdleTimeMillis(long minEvictableIdleTimeMillis) { 964 _minEvictableIdleTimeMillis = minEvictableIdleTimeMillis; 965 } 966 967 /** 968 * When <code>true</code>, objects will be 969 * {@link org.apache.commons.pool.PoolableObjectFactory#validateObject validated} 970 * by the idle object evictor (if any). If an object 971 * fails to validate, it will be dropped from the pool. 972 * 973 * @return <code>true</code> when objects are validated when borrowed. 974 * @see #setTestWhileIdle 975 * @see #setTimeBetweenEvictionRunsMillis 976 */ 977 public synchronized boolean getTestWhileIdle() { 978 return _testWhileIdle; 979 } 980 981 /** 982 * When <code>true</code>, objects will be 983 * {@link org.apache.commons.pool.PoolableObjectFactory#validateObject validated} 984 * by the idle object evictor (if any). If an object 985 * fails to validate, it will be dropped from the pool. 986 * 987 * @param testWhileIdle <code>true</code> so objects are validated when borrowed. 988 * @see #getTestWhileIdle 989 * @see #setTimeBetweenEvictionRunsMillis 990 */ 991 public synchronized void setTestWhileIdle(boolean testWhileIdle) { 992 _testWhileIdle = testWhileIdle; 993 } 994 995 /** 996 * Sets the configuration. 997 * @param conf the new configuration to use. 998 * @see GenericKeyedObjectPool.Config 999 */ 1000 public synchronized void setConfig(GenericKeyedObjectPool.Config conf) { 1001 setMaxIdle(conf.maxIdle); 1002 setMaxActive(conf.maxActive); 1003 setMaxTotal(conf.maxTotal); 1004 setMinIdle(conf.minIdle); 1005 setMaxWait(conf.maxWait); 1006 setWhenExhaustedAction(conf.whenExhaustedAction); 1007 setTestOnBorrow(conf.testOnBorrow); 1008 setTestOnReturn(conf.testOnReturn); 1009 setTestWhileIdle(conf.testWhileIdle); 1010 setNumTestsPerEvictionRun(conf.numTestsPerEvictionRun); 1011 setMinEvictableIdleTimeMillis(conf.minEvictableIdleTimeMillis); 1012 setTimeBetweenEvictionRunsMillis(conf.timeBetweenEvictionRunsMillis); 1013 } 1014 1015 /** 1016 * Whether or not the idle object pools act as LIFO queues. True means 1017 * that borrowObject returns the most recently used ("last in") idle object 1018 * in a pool (if there are idle instances available). False means that 1019 * the pools behave as FIFO queues - objects are taken from idle object 1020 * pools in the order that they are returned. 1021 * 1022 * @return <code>true</code> if the pools are configured to act as LIFO queues 1023 * @since 1.4 1024 */ 1025 public synchronized boolean getLifo() { 1026 return _lifo; 1027 } 1028 1029 /** 1030 * Sets the LIFO property of the pools. True means that borrowObject returns 1031 * the most recently used ("last in") idle object in a pool (if there are 1032 * idle instances available). False means that the pools behave as FIFO 1033 * queues - objects are taken from idle object pools in the order that 1034 * they are returned. 1035 * 1036 * @param lifo the new value for the lifo property 1037 * @since 1.4 1038 */ 1039 public synchronized void setLifo(boolean lifo) { 1040 this._lifo = lifo; 1041 } 1042 1043 //-- ObjectPool methods ------------------------------------------ 1044 1045 /** 1046 * <p>Borrows an object from the keyed pool associated with the given key.</p> 1047 * 1048 * <p>If there is an idle instance available in the pool associated with the given key, then 1049 * either the most-recently returned (if {@link #getLifo() lifo} == true) or "oldest" (lifo == false) 1050 * instance sitting idle in the pool will be activated and returned. If activation fails, or 1051 * {@link #getTestOnBorrow() testOnBorrow} is set to true and validation fails, the instance is destroyed and the 1052 * next available instance is examined. This continues until either a valid instance is returned or there 1053 * are no more idle instances available.</p> 1054 * 1055 * <p>If there are no idle instances available in the pool associated with the given key, behavior 1056 * depends on the {@link #getMaxActive() maxActive}, {@link #getMaxTotal() maxTotal}, and (if applicable) 1057 * {@link #getWhenExhaustedAction() whenExhaustedAction} and {@link #getMaxWait() maxWait} properties. If the 1058 * number of instances checked out from the pool under the given key is less than <code>maxActive</code> and 1059 * the total number of instances in circulation (under all keys) is less than <code>maxTotal</code>, a new instance 1060 * is created, activated and (if applicable) validated and returned to the caller.</p> 1061 * 1062 * <p>If the associated keyed pool is exhausted (no available idle instances and no capacity to create new ones), 1063 * this method will either block ({@link #WHEN_EXHAUSTED_BLOCK}), throw a <code>NoSuchElementException</code> 1064 * ({@link #WHEN_EXHAUSTED_FAIL}), or grow ({@link #WHEN_EXHAUSTED_GROW} - ignoring maxActive, maxTotal properties). 1065 * The length of time that this method will block when <code>whenExhaustedAction == WHEN_EXHAUSTED_BLOCK</code> 1066 * is determined by the {@link #getMaxWait() maxWait} property.</p> 1067 * 1068 * <p>When the pool is exhausted, multiple calling threads may be simultaneously blocked waiting for instances 1069 * to become available. As of pool 1.5, a "fairness" algorithm has been implemented to ensure that threads receive 1070 * available instances in request arrival order.</p> 1071 * 1072 * @param key pool key 1073 * @return object instance from the keyed pool 1074 * @throws NoSuchElementException if a keyed object instance cannot be returned. 1075 */ 1076 public Object borrowObject(Object key) throws Exception { 1077 long starttime = System.currentTimeMillis(); 1078 Latch latch = new Latch(key); 1079 byte whenExhaustedAction; 1080 long maxWait; 1081 synchronized (this) { 1082 // Get local copy of current config. Can't sync when used later as 1083 // it can result in a deadlock. Has the added advantage that config 1084 // is consistent for entire method execution 1085 whenExhaustedAction = _whenExhaustedAction; 1086 maxWait = _maxWait; 1087 1088 // Add this request to the queue 1089 _allocationQueue.add(latch); 1090 1091 // Work the allocation queue, allocating idle instances and 1092 // instance creation permits in request arrival order 1093 allocate(); 1094 } 1095 1096 for(;;) { 1097 synchronized (this) { 1098 assertOpen(); 1099 } 1100 // If no object was allocated 1101 if (null == latch.getPair()) { 1102 // Check to see if we were allowed to create one 1103 if (latch.mayCreate()) { 1104 // allow new object to be created 1105 } else { 1106 // the pool is exhausted 1107 switch(whenExhaustedAction) { 1108 case WHEN_EXHAUSTED_GROW: 1109 // allow new object to be created 1110 synchronized (this) { 1111 // Make sure allocate hasn't already assigned an object 1112 // in a different thread 1113 if (latch.getPair() == null) { 1114 _allocationQueue.remove(latch); 1115 latch.getPool().incrementInternalProcessingCount(); 1116 } 1117 } 1118 break; 1119 case WHEN_EXHAUSTED_FAIL: 1120 synchronized (this) { 1121 // Make sure allocate hasn't already assigned an object 1122 // in a different thread 1123 if (latch.getPair() != null) { 1124 break; 1125 } 1126 _allocationQueue.remove(latch); 1127 } 1128 throw new NoSuchElementException("Pool exhausted"); 1129 case WHEN_EXHAUSTED_BLOCK: 1130 try { 1131 synchronized (latch) { 1132 // Before we wait, make sure another thread didn't allocate us an object 1133 if (latch.getPair() == null) { 1134 if (maxWait <= 0) { 1135 latch.wait(); 1136 } else { 1137 // this code may be executed again after a notify then continue cycle 1138 // so, need to calculate the amount of time to wait 1139 final long elapsed = (System.currentTimeMillis() - starttime); 1140 final long waitTime = maxWait - elapsed; 1141 if (waitTime > 0) 1142 { 1143 latch.wait(waitTime); 1144 } 1145 } 1146 } else { 1147 break; 1148 } 1149 } 1150 } catch(InterruptedException e) { 1151 Thread.currentThread().interrupt(); 1152 throw e; 1153 } 1154 if (maxWait > 0 && ((System.currentTimeMillis() - starttime) >= maxWait)) { 1155 synchronized (this) { 1156 // Make sure allocate hasn't already assigned an object 1157 // in a different thread 1158 if (latch.getPair() == null) { 1159 _allocationQueue.remove(latch); 1160 } else { 1161 break; 1162 } 1163 } 1164 throw new NoSuchElementException("Timeout waiting for idle object"); 1165 } else { 1166 continue; // keep looping 1167 } 1168 default: 1169 throw new IllegalArgumentException("whenExhaustedAction " + whenExhaustedAction + 1170 " not recognized."); 1171 } 1172 } 1173 } 1174 1175 boolean newlyCreated = false; 1176 if (null == latch.getPair()) { 1177 try { 1178 Object obj = _factory.makeObject(key); 1179 latch.setPair(new ObjectTimestampPair(obj)); 1180 newlyCreated = true; 1181 } finally { 1182 if (!newlyCreated) { 1183 // object cannot be created 1184 synchronized (this) { 1185 latch.getPool().decrementInternalProcessingCount(); 1186 // No need to reset latch - about to throw exception 1187 allocate(); 1188 } 1189 } 1190 } 1191 } 1192 1193 // activate & validate the object 1194 try { 1195 _factory.activateObject(key, latch.getPair().value); 1196 if (_testOnBorrow && !_factory.validateObject(key, latch.getPair().value)) { 1197 throw new Exception("ValidateObject failed"); 1198 } 1199 synchronized (this) { 1200 latch.getPool().decrementInternalProcessingCount(); 1201 latch.getPool().incrementActiveCount(); 1202 } 1203 return latch.getPair().value; 1204 } catch (Throwable e) { 1205 // object cannot be activated or is invalid 1206 try { 1207 _factory.destroyObject(key, latch.getPair().value); 1208 } catch (Throwable e2) { 1209 // cannot destroy broken object 1210 } 1211 synchronized (this) { 1212 latch.getPool().decrementInternalProcessingCount(); 1213 latch.reset(); 1214 _allocationQueue.add(0, latch); 1215 allocate(); 1216 } 1217 if (newlyCreated) { 1218 throw new NoSuchElementException( 1219 "Could not create a validated object, cause: " + 1220 e.getMessage()); 1221 } 1222 else { 1223 continue; // keep looping 1224 } 1225 } 1226 } 1227 } 1228 1229 /** 1230 * Allocate available instances to latches in the allocation queue. Then 1231 * set _mayCreate to true for as many additional latches remaining in queue 1232 * as _maxActive allows for each key. 1233 */ 1234 private void allocate() { 1235 boolean clearOldest = false; 1236 1237 synchronized (this) { 1238 if (isClosed()) return; 1239 1240 Iterator allocationQueueIter = _allocationQueue.iterator(); 1241 1242 while (allocationQueueIter.hasNext()) { 1243 // First use any objects in the pool to clear the queue 1244 Latch latch = (Latch) allocationQueueIter.next(); 1245 ObjectQueue pool = (ObjectQueue)(_poolMap.get(latch.getkey())); 1246 if (null == pool) { 1247 pool = new ObjectQueue(); 1248 _poolMap.put(latch.getkey(), pool); 1249 _poolList.add(latch.getkey()); 1250 } 1251 latch.setPool(pool); 1252 if (!pool.queue.isEmpty()) { 1253 allocationQueueIter.remove(); 1254 latch.setPair( 1255 (ObjectTimestampPair) pool.queue.removeFirst()); 1256 pool.incrementInternalProcessingCount(); 1257 _totalIdle--; 1258 synchronized (latch) { 1259 latch.notify(); 1260 } 1261 // Next item in queue 1262 continue; 1263 } 1264 1265 // If there is a totalMaxActive and we are at the limit then 1266 // we have to make room 1267 if ((_maxTotal > 0) && 1268 (_totalActive + _totalIdle + _totalInternalProcessing >= _maxTotal)) { 1269 clearOldest = true; 1270 break; 1271 } 1272 1273 // Second utilise any spare capacity to create new objects 1274 if ((_maxActive < 0 || pool.activeCount + pool.internalProcessingCount < _maxActive) && 1275 (_maxTotal < 0 || _totalActive + _totalIdle + _totalInternalProcessing < _maxTotal)) { 1276 // allow new object to be created 1277 allocationQueueIter.remove(); 1278 latch.setMayCreate(true); 1279 pool.incrementInternalProcessingCount(); 1280 synchronized (latch) { 1281 latch.notify(); 1282 } 1283 // Next item in queue 1284 continue; 1285 } 1286 1287 // If there is no per-key limit and we reach this point we 1288 // must have allocated all the objects we possibly can and there 1289 // is no point looking at the rest of the allocation queue 1290 if (_maxActive < 0) { 1291 break; 1292 } 1293 } 1294 } 1295 1296 if (clearOldest) { 1297 /* Clear oldest calls factory methods so it must be called from 1298 * outside the sync block. 1299 * It also needs to be outside the sync block as it calls 1300 * allocate(). If called inside the sync block, the call to 1301 * allocate() would be able to enter the sync block (since the 1302 * thread already has the lock) which may have unexpected, 1303 * unpleasant results. 1304 */ 1305 clearOldest(); 1306 } 1307 } 1308 1309 /** 1310 * Clears any objects sitting idle in the pool by removing them from the 1311 * idle instance pool and then invoking the configured 1312 * {@link KeyedPoolableObjectFactory#destroyObject(Object, Object)} method on 1313 * each idle instance. 1314 * 1315 * <p> Implementation notes: 1316 * <ul><li>This method does not destroy or effect in any way instances that are 1317 * checked out when it is invoked.</li> 1318 * <li>Invoking this method does not prevent objects being 1319 * returned to the idle instance pool, even during its execution. It locks 1320 * the pool only during instance removal. Additional instances may be returned 1321 * while removed items are being destroyed.</li></ul></p> 1322 */ 1323 public void clear() { 1324 Map toDestroy = new HashMap(); 1325 synchronized (this) { 1326 for (Iterator it = _poolMap.keySet().iterator(); it.hasNext();) { 1327 Object key = it.next(); 1328 ObjectQueue pool = (ObjectQueue)_poolMap.get(key); 1329 // Copy objects to new list so pool.queue can be cleared inside 1330 // the sync 1331 List objects = new ArrayList(); 1332 objects.addAll(pool.queue); 1333 toDestroy.put(key, objects); 1334 it.remove(); 1335 _poolList.remove(key); 1336 _totalIdle = _totalIdle - pool.queue.size(); 1337 _totalInternalProcessing = 1338 _totalInternalProcessing + pool.queue.size(); 1339 pool.queue.clear(); 1340 } 1341 } 1342 destroy(toDestroy); 1343 } 1344 1345 /** 1346 * Clears oldest 15% of objects in pool. The method sorts the 1347 * objects into a TreeMap and then iterates the first 15% for removal. 1348 * 1349 * @since Pool 1.3 1350 */ 1351 public void clearOldest() { 1352 // Map of objects to destroy my key 1353 final Map toDestroy = new HashMap(); 1354 1355 // build sorted map of idle objects 1356 final Map map = new TreeMap(); 1357 synchronized (this) { 1358 for (Iterator keyiter = _poolMap.keySet().iterator(); keyiter.hasNext();) { 1359 final Object key = keyiter.next(); 1360 final CursorableLinkedList list = ((ObjectQueue)_poolMap.get(key)).queue; 1361 for (Iterator it = list.iterator(); it.hasNext();) { 1362 // each item into the map uses the objectimestamppair object 1363 // as the key. It then gets sorted based on the timstamp field 1364 // each value in the map is the parent list it belongs in. 1365 map.put(it.next(), key); 1366 } 1367 } 1368 1369 // Now iterate created map and kill the first 15% plus one to account for zero 1370 Set setPairKeys = map.entrySet(); 1371 int itemsToRemove = ((int) (map.size() * 0.15)) + 1; 1372 1373 Iterator iter = setPairKeys.iterator(); 1374 while (iter.hasNext() && itemsToRemove > 0) { 1375 Map.Entry entry = (Map.Entry) iter.next(); 1376 // kind of backwards on naming. In the map, each key is the objecttimestamppair 1377 // because it has the ordering with the timestamp value. Each value that the 1378 // key references is the key of the list it belongs to. 1379 Object key = entry.getValue(); 1380 ObjectTimestampPair pairTimeStamp = (ObjectTimestampPair) entry.getKey(); 1381 final CursorableLinkedList list = 1382 ((ObjectQueue)(_poolMap.get(key))).queue; 1383 list.remove(pairTimeStamp); 1384 1385 if (toDestroy.containsKey(key)) { 1386 ((List)toDestroy.get(key)).add(pairTimeStamp); 1387 } else { 1388 List listForKey = new ArrayList(); 1389 listForKey.add(pairTimeStamp); 1390 toDestroy.put(key, listForKey); 1391 } 1392 // if that was the last object for that key, drop that pool 1393 if (list.isEmpty()) { 1394 _poolMap.remove(key); 1395 _poolList.remove(key); 1396 } 1397 _totalIdle--; 1398 _totalInternalProcessing++; 1399 itemsToRemove--; 1400 } 1401 1402 } 1403 destroy(toDestroy); 1404 } 1405 1406 /** 1407 * Clears the specified pool, removing all pooled instances corresponding to the given <code>key</code>. 1408 * 1409 * @param key the key to clear 1410 */ 1411 public void clear(Object key) { 1412 Map toDestroy = new HashMap(); 1413 1414 final ObjectQueue pool; 1415 synchronized (this) { 1416 pool = (ObjectQueue)(_poolMap.remove(key)); 1417 if (pool == null) { 1418 return; 1419 } else { 1420 _poolList.remove(key); 1421 } 1422 // Copy objects to new list so pool.queue can be cleared inside 1423 // the sync 1424 List objects = new ArrayList(); 1425 objects.addAll(pool.queue); 1426 toDestroy.put(key, objects); 1427 _totalIdle = _totalIdle - pool.queue.size(); 1428 _totalInternalProcessing = 1429 _totalInternalProcessing + pool.queue.size(); 1430 pool.queue.clear(); 1431 } 1432 destroy(toDestroy); 1433 } 1434 1435 /** 1436 * Assuming Map<Object,Collection<ObjectTimestampPair>>, destroy all 1437 * ObjectTimestampPair.value 1438 * 1439 * @param m Map containing keyed pools to clear 1440 */ 1441 private void destroy(Map m) { 1442 for (Iterator keys = m.keySet().iterator(); keys.hasNext();) { 1443 Object key = keys.next(); 1444 Collection c = (Collection) m.get(key); 1445 for (Iterator it = c.iterator(); it.hasNext();) { 1446 try { 1447 _factory.destroyObject( 1448 key,((ObjectTimestampPair)(it.next())).value); 1449 } catch(Exception e) { 1450 // ignore error, keep destroying the rest 1451 } finally { 1452 synchronized(this) { 1453 _totalInternalProcessing--; 1454 allocate(); 1455 } 1456 } 1457 } 1458 1459 } 1460 } 1461 1462 /** 1463 * Returns the total number of instances current borrowed from this pool but not yet returned. 1464 * 1465 * @return the total number of instances currently borrowed from this pool 1466 */ 1467 public synchronized int getNumActive() { 1468 return _totalActive; 1469 } 1470 1471 /** 1472 * Returns the total number of instances currently idle in this pool. 1473 * 1474 * @return the total number of instances currently idle in this pool 1475 */ 1476 public synchronized int getNumIdle() { 1477 return _totalIdle; 1478 } 1479 1480 /** 1481 * Returns the number of instances currently borrowed from but not yet returned 1482 * to the pool corresponding to the given <code>key</code>. 1483 * 1484 * @param key the key to query 1485 * @return the number of instances corresponding to the given <code>key</code> currently borrowed in this pool 1486 */ 1487 public synchronized int getNumActive(Object key) { 1488 final ObjectQueue pool = (ObjectQueue)(_poolMap.get(key)); 1489 return pool != null ? pool.activeCount : 0; 1490 } 1491 1492 /** 1493 * Returns the number of instances corresponding to the given <code>key</code> currently idle in this pool. 1494 * 1495 * @param key the key to query 1496 * @return the number of instances corresponding to the given <code>key</code> currently idle in this pool 1497 */ 1498 public synchronized int getNumIdle(Object key) { 1499 final ObjectQueue pool = (ObjectQueue)(_poolMap.get(key)); 1500 return pool != null ? pool.queue.size() : 0; 1501 } 1502 1503 /** 1504 * <p>Returns an object to a keyed pool.</p> 1505 * 1506 * <p>For the pool to function correctly, the object instance <strong>must</strong> have been borrowed 1507 * from the pool (under the same key) and not yet returned. Repeated <code>returnObject</code> calls on 1508 * the same object/key pair (with no <code>borrowObject</code> calls in between) will result in multiple 1509 * references to the object in the idle instance pool.</p> 1510 * 1511 * <p>If {@link #getMaxIdle() maxIdle} is set to a positive value and the number of idle instances under the given 1512 * key has reached this value, the returning instance is destroyed.</p> 1513 * 1514 * <p>If {@link #getTestOnReturn() testOnReturn} == true, the returning instance is validated before being returned 1515 * to the idle instance pool under the given key. In this case, if validation fails, the instance is destroyed.</p> 1516 * 1517 * @param key pool key 1518 * @param obj instance to return to the keyed pool 1519 * @throws Exception 1520 */ 1521 public void returnObject(Object key, Object obj) throws Exception { 1522 try { 1523 addObjectToPool(key, obj, true); 1524 } catch (Exception e) { 1525 if (_factory != null) { 1526 try { 1527 _factory.destroyObject(key, obj); 1528 } catch (Exception e2) { 1529 // swallowed 1530 } 1531 // TODO: Correctness here depends on control in addObjectToPool. 1532 // These two methods should be refactored, removing the 1533 // "behavior flag", decrementNumActive, from addObjectToPool. 1534 ObjectQueue pool = (ObjectQueue) (_poolMap.get(key)); 1535 if (pool != null) { 1536 synchronized(this) { 1537 pool.decrementActiveCount(); 1538 allocate(); 1539 } 1540 } 1541 } 1542 } 1543 } 1544 1545 /** 1546 * <p>Adds an object to the keyed pool.</p> 1547 * 1548 * <p>Validates the object if testOnReturn == true and passivates it before returning it to the pool. 1549 * if validation or passivation fails, or maxIdle is set and there is no room in the pool, the instance 1550 * is destroyed.</p> 1551 * 1552 * <p>Calls {@link #allocate()} on successful completion</p> 1553 * 1554 * @param key pool key 1555 * @param obj instance to add to the keyed pool 1556 * @param decrementNumActive whether or not to decrement the active count associated with the keyed pool 1557 * @throws Exception 1558 */ 1559 private void addObjectToPool(Object key, Object obj, 1560 boolean decrementNumActive) throws Exception { 1561 1562 // if we need to validate this object, do so 1563 boolean success = true; // whether or not this object passed validation 1564 if (_testOnReturn && !_factory.validateObject(key, obj)) { 1565 success = false; 1566 } else { 1567 _factory.passivateObject(key, obj); 1568 } 1569 1570 boolean shouldDestroy = !success; 1571 ObjectQueue pool; 1572 1573 // Add instance to pool if there is room and it has passed validation 1574 // (if testOnreturn is set) 1575 synchronized (this) { 1576 // grab the pool (list) of objects associated with the given key 1577 pool = (ObjectQueue) (_poolMap.get(key)); 1578 // if it doesn't exist, create it 1579 if (null == pool) { 1580 pool = new ObjectQueue(); 1581 _poolMap.put(key, pool); 1582 _poolList.add(key); 1583 } 1584 if (isClosed()) { 1585 shouldDestroy = true; 1586 } else { 1587 // if there's no space in the pool, flag the object for destruction 1588 // else if we passivated successfully, return it to the pool 1589 if (_maxIdle >= 0 && (pool.queue.size() >= _maxIdle)) { 1590 shouldDestroy = true; 1591 } else if (success) { 1592 // borrowObject always takes the first element from the queue, 1593 // so for LIFO, push on top, FIFO add to end 1594 if (_lifo) { 1595 pool.queue.addFirst(new ObjectTimestampPair(obj)); 1596 } else { 1597 pool.queue.addLast(new ObjectTimestampPair(obj)); 1598 } 1599 _totalIdle++; 1600 if (decrementNumActive) { 1601 pool.decrementActiveCount(); 1602 } 1603 allocate(); 1604 } 1605 } 1606 } 1607 1608 // Destroy the instance if necessary 1609 if (shouldDestroy) { 1610 try { 1611 _factory.destroyObject(key, obj); 1612 } catch(Exception e) { 1613 // ignored? 1614 } 1615 // Decrement active count *after* destroy if applicable 1616 if (decrementNumActive) { 1617 synchronized(this) { 1618 pool.decrementActiveCount(); 1619 allocate(); 1620 } 1621 } 1622 } 1623 } 1624 1625 /** 1626 * <p>Invalidates the object instance associated with the given key. Decrements the active count 1627 * associated with the given keyed pool and destroys the instance.</p> 1628 * 1629 * @param key pool key 1630 * @param obj instance to invalidate 1631 * @throws Exception if an exception occurs destroying the object 1632 */ 1633 public void invalidateObject(Object key, Object obj) throws Exception { 1634 try { 1635 _factory.destroyObject(key, obj); 1636 } finally { 1637 synchronized (this) { 1638 ObjectQueue pool = (ObjectQueue) (_poolMap.get(key)); 1639 if (null == pool) { 1640 pool = new ObjectQueue(); 1641 _poolMap.put(key, pool); 1642 _poolList.add(key); 1643 } 1644 pool.decrementActiveCount(); 1645 allocate(); // _totalActive has changed 1646 } 1647 } 1648 } 1649 1650 /** 1651 * Create an object using the {@link KeyedPoolableObjectFactory#makeObject factory}, 1652 * passivate it, and then place it in the idle object pool. 1653 * <code>addObject</code> is useful for "pre-loading" a pool with idle objects. 1654 * 1655 * @param key the key a new instance should be added to 1656 * @throws Exception when {@link KeyedPoolableObjectFactory#makeObject} fails. 1657 * @throws IllegalStateException when no {@link #setFactory factory} has been set or after {@link #close} has been 1658 * called on this pool. 1659 */ 1660 public void addObject(Object key) throws Exception { 1661 assertOpen(); 1662 if (_factory == null) { 1663 throw new IllegalStateException("Cannot add objects without a factory."); 1664 } 1665 Object obj = _factory.makeObject(key); 1666 try { 1667 assertOpen(); 1668 addObjectToPool(key, obj, false); 1669 } catch (IllegalStateException ex) { // Pool closed 1670 try { 1671 _factory.destroyObject(key, obj); 1672 } catch (Exception ex2) { 1673 // swallow 1674 } 1675 throw ex; 1676 } 1677 } 1678 1679 /** 1680 * Registers a key for pool control. 1681 * 1682 * If <code>populateImmediately</code> is <code>true</code> and 1683 * <code>minIdle > 0,</code> the pool under the given key will be 1684 * populated immediately with <code>minIdle</code> idle instances. 1685 * 1686 * @param key - The key to register for pool control. 1687 * @param populateImmediately - If this is <code>true</code>, the pool 1688 * will be populated immediately. 1689 * @since Pool 1.3 1690 */ 1691 public synchronized void preparePool(Object key, boolean populateImmediately) { 1692 ObjectQueue pool = (ObjectQueue)(_poolMap.get(key)); 1693 if (null == pool) { 1694 pool = new ObjectQueue(); 1695 _poolMap.put(key,pool); 1696 _poolList.add(key); 1697 } 1698 1699 if (populateImmediately) { 1700 try { 1701 // Create the pooled objects 1702 ensureMinIdle(key); 1703 } 1704 catch (Exception e) { 1705 //Do nothing 1706 } 1707 } 1708 } 1709 1710 /** 1711 * Closes the keyed object pool. Once the pool is closed, {@link #borrowObject(Object)} 1712 * will fail with IllegalStateException, but {@link #returnObject(Object, Object)} and 1713 * {@link #invalidateObject(Object, Object)} will continue to work. This method does not 1714 * {@link #clear()} the pool. The method is idempotent - that is, it is OK to call it on a closed 1715 * pool. 1716 * 1717 * @throws Exception 1718 */ 1719 public void close() throws Exception { 1720 super.close(); 1721 synchronized (this) { 1722 clear(); 1723 if (null != _evictionCursor) { 1724 _evictionCursor.close(); 1725 _evictionCursor = null; 1726 } 1727 if (null != _evictionKeyCursor) { 1728 _evictionKeyCursor.close(); 1729 _evictionKeyCursor = null; 1730 } 1731 startEvictor(-1L); 1732 } 1733 } 1734 1735 /** 1736 * <p>Sets the keyed poolable object factory associated with this pool.</p> 1737 * 1738 * <p>If this method is called when objects are checked out of any of the keyed pools, 1739 * an IllegalStateException is thrown. Calling this method also has the side effect of 1740 * destroying any idle instances in existing keyed pools.</p> 1741 * 1742 * @param factory KeyedPoolableObjectFactory to use when creating keyed object pool instances 1743 * @throws IllegalStateException if there are active (checked out) instances associated with this keyed object pool 1744 */ 1745 public void setFactory(KeyedPoolableObjectFactory factory) throws IllegalStateException { 1746 Map toDestroy = new HashMap(); 1747 synchronized (this) { 1748 assertOpen(); 1749 if (0 < getNumActive()) { 1750 throw new IllegalStateException("Objects are already active"); 1751 } else { 1752 for (Iterator it = _poolMap.keySet().iterator(); it.hasNext();) { 1753 Object key = it.next(); 1754 ObjectQueue pool = (ObjectQueue)_poolMap.get(key); 1755 if (pool != null) { 1756 // Copy objects to new list so pool.queue can be cleared 1757 // inside the sync 1758 List objects = new ArrayList(); 1759 objects.addAll(pool.queue); 1760 toDestroy.put(key, objects); 1761 it.remove(); 1762 _poolList.remove(key); 1763 _totalIdle = _totalIdle - pool.queue.size(); 1764 _totalInternalProcessing = 1765 _totalInternalProcessing + pool.queue.size(); 1766 pool.queue.clear(); 1767 } 1768 } 1769 _factory = factory; 1770 } 1771 } 1772 destroy(toDestroy); 1773 } 1774 1775 /** 1776 * <p>Perform <code>numTests</code> idle object eviction tests, evicting 1777 * examined objects that meet the criteria for eviction. If 1778 * <code>testWhileIdle</code> is true, examined objects are validated 1779 * when visited (and removed if invalid); otherwise only objects that 1780 * have been idle for more than <code>minEvicableIdletimeMillis</code> 1781 * are removed.</p> 1782 * 1783 * <p>Successive activations of this method examine objects in keyed pools 1784 * in sequence, cycling through the keys and examining objects in 1785 * oldest-to-youngest order within the keyed pools.</p> 1786 * 1787 * @throws Exception when there is a problem evicting idle objects. 1788 */ 1789 public void evict() throws Exception { 1790 Object key = null; 1791 boolean testWhileIdle; 1792 long minEvictableIdleTimeMillis; 1793 1794 synchronized (this) { 1795 // Get local copy of current config. Can't sync when used later as 1796 // it can result in a deadlock. Has the added advantage that config 1797 // is consistent for entire method execution 1798 testWhileIdle = _testWhileIdle; 1799 minEvictableIdleTimeMillis = _minEvictableIdleTimeMillis; 1800 1801 // Initialize key to last key value 1802 if (_evictionKeyCursor != null && 1803 _evictionKeyCursor._lastReturned != null) { 1804 key = _evictionKeyCursor._lastReturned.value(); 1805 } 1806 } 1807 1808 for (int i=0, m=getNumTests(); i<m; i++) { 1809 final ObjectTimestampPair pair; 1810 synchronized (this) { 1811 // make sure pool map is not empty; otherwise do nothing 1812 if (_poolMap == null || _poolMap.size() == 0) { 1813 continue; 1814 } 1815 1816 // if we don't have a key cursor, then create one 1817 if (null == _evictionKeyCursor) { 1818 resetEvictionKeyCursor(); 1819 key = null; 1820 } 1821 1822 // if we don't have an object cursor, create one 1823 if (null == _evictionCursor) { 1824 // if the _evictionKeyCursor has a next value, use this key 1825 if (_evictionKeyCursor.hasNext()) { 1826 key = _evictionKeyCursor.next(); 1827 resetEvictionObjectCursor(key); 1828 } else { 1829 // Reset the key cursor and try again 1830 resetEvictionKeyCursor(); 1831 if (_evictionKeyCursor != null) { 1832 if (_evictionKeyCursor.hasNext()) { 1833 key = _evictionKeyCursor.next(); 1834 resetEvictionObjectCursor(key); 1835 } 1836 } 1837 } 1838 } 1839 1840 if (_evictionCursor == null) { 1841 continue; // should never happen; do nothing 1842 } 1843 1844 // If eviction cursor is exhausted, try to move 1845 // to the next key and reset 1846 if ((_lifo && !_evictionCursor.hasPrevious()) || 1847 (!_lifo && !_evictionCursor.hasNext())) { 1848 if (_evictionKeyCursor != null) { 1849 if (_evictionKeyCursor.hasNext()) { 1850 key = _evictionKeyCursor.next(); 1851 resetEvictionObjectCursor(key); 1852 } else { // Need to reset Key cursor 1853 resetEvictionKeyCursor(); 1854 if (_evictionKeyCursor != null) { 1855 if (_evictionKeyCursor.hasNext()) { 1856 key = _evictionKeyCursor.next(); 1857 resetEvictionObjectCursor(key); 1858 } 1859 } 1860 } 1861 } 1862 } 1863 1864 if ((_lifo && !_evictionCursor.hasPrevious()) || 1865 (!_lifo && !_evictionCursor.hasNext())) { 1866 continue; // reset failed, do nothing 1867 } 1868 1869 // if LIFO and the _evictionCursor has a previous object, 1870 // or FIFO and _evictionCursor has a next object, test it 1871 pair = _lifo ? 1872 (ObjectTimestampPair) _evictionCursor.previous() : 1873 (ObjectTimestampPair) _evictionCursor.next(); 1874 _evictionCursor.remove(); 1875 _totalIdle--; 1876 _totalInternalProcessing++; 1877 } 1878 1879 boolean removeObject=false; 1880 if ((minEvictableIdleTimeMillis > 0) && 1881 (System.currentTimeMillis() - pair.tstamp > 1882 minEvictableIdleTimeMillis)) { 1883 removeObject=true; 1884 } 1885 if (testWhileIdle && removeObject == false) { 1886 boolean active = false; 1887 try { 1888 _factory.activateObject(key,pair.value); 1889 active = true; 1890 } catch(Exception e) { 1891 removeObject=true; 1892 } 1893 if (active) { 1894 if (!_factory.validateObject(key,pair.value)) { 1895 removeObject=true; 1896 } else { 1897 try { 1898 _factory.passivateObject(key,pair.value); 1899 } catch(Exception e) { 1900 removeObject=true; 1901 } 1902 } 1903 } 1904 } 1905 1906 if (removeObject) { 1907 try { 1908 _factory.destroyObject(key, pair.value); 1909 } catch(Exception e) { 1910 // ignored 1911 } finally { 1912 // Do not remove the key from the _poolList or _poolmap, 1913 // even if the list stored in the _poolMap for this key is 1914 // empty when minIdle > 0. 1915 // 1916 // Otherwise if it was the last object for that key, 1917 // drop that pool 1918 if (_minIdle == 0) { 1919 synchronized (this) { 1920 ObjectQueue objectQueue = 1921 (ObjectQueue)_poolMap.get(key); 1922 if (objectQueue != null && 1923 objectQueue.queue.isEmpty()) { 1924 _poolMap.remove(key); 1925 _poolList.remove(key); 1926 } 1927 } 1928 } 1929 } 1930 } 1931 synchronized (this) { 1932 if (!removeObject) { 1933 _evictionCursor.add(pair); 1934 _totalIdle++; 1935 if (_lifo) { 1936 // Skip over the element we just added back 1937 _evictionCursor.previous(); 1938 } 1939 } 1940 _totalInternalProcessing--; 1941 } 1942 } 1943 } 1944 1945 /** 1946 * Resets the eviction key cursor and closes any 1947 * associated eviction object cursor 1948 */ 1949 private void resetEvictionKeyCursor() { 1950 if (_evictionKeyCursor != null) { 1951 _evictionKeyCursor.close(); 1952 } 1953 _evictionKeyCursor = _poolList.cursor(); 1954 if (null != _evictionCursor) { 1955 _evictionCursor.close(); 1956 _evictionCursor = null; 1957 } 1958 } 1959 1960 /** 1961 * Resets the eviction object cursor for the given key 1962 * 1963 * @param key eviction key 1964 */ 1965 private void resetEvictionObjectCursor(Object key) { 1966 if (_evictionCursor != null) { 1967 _evictionCursor.close(); 1968 } 1969 if (_poolMap == null) { 1970 return; 1971 } 1972 ObjectQueue pool = (ObjectQueue) (_poolMap.get(key)); 1973 if (pool != null) { 1974 CursorableLinkedList queue = pool.queue; 1975 _evictionCursor = queue.cursor(_lifo ? queue.size() : 0); 1976 } 1977 } 1978 1979 /** 1980 * Iterates through all the known keys and creates any necessary objects to maintain 1981 * the minimum level of pooled objects. 1982 * @see #getMinIdle 1983 * @see #setMinIdle 1984 * @throws Exception If there was an error whilst creating the pooled objects. 1985 */ 1986 private void ensureMinIdle() throws Exception { 1987 //Check if should sustain the pool 1988 if (_minIdle > 0) { 1989 Object[] keysCopy; 1990 synchronized(this) { 1991 // Get the current set of keys 1992 keysCopy = _poolMap.keySet().toArray(); 1993 } 1994 1995 // Loop through all elements in _poolList 1996 // Find out the total number of max active and max idle for that class 1997 // If the number is less than the minIdle, do creation loop to boost numbers 1998 for (int i=0; i < keysCopy.length; i++) { 1999 //Get the next key to process 2000 ensureMinIdle(keysCopy[i]); 2001 } 2002 } 2003 } 2004 2005 /** 2006 * Re-creates any needed objects to maintain the minimum levels of 2007 * pooled objects for the specified key. 2008 * 2009 * This method uses {@link #calculateDefecit} to calculate the number 2010 * of objects to be created. {@link #calculateDefecit} can be overridden to 2011 * provide a different method of calculating the number of objects to be 2012 * created. 2013 * @param key The key to process 2014 * @throws Exception If there was an error whilst creating the pooled objects 2015 */ 2016 private void ensureMinIdle(Object key) throws Exception { 2017 // Calculate current pool objects 2018 ObjectQueue pool; 2019 synchronized(this) { 2020 pool = (ObjectQueue)(_poolMap.get(key)); 2021 } 2022 if (pool == null) { 2023 return; 2024 } 2025 2026 // this method isn't synchronized so the 2027 // calculateDeficit is done at the beginning 2028 // as a loop limit and a second time inside the loop 2029 // to stop when another thread already returned the 2030 // needed objects 2031 int objectDeficit = calculateDefecit(pool, false); 2032 2033 for (int i = 0; i < objectDeficit && calculateDefecit(pool, true) > 0; i++) { 2034 try { 2035 addObject(key); 2036 } finally { 2037 synchronized (this) { 2038 pool.decrementInternalProcessingCount(); 2039 allocate(); 2040 } 2041 } 2042 } 2043 } 2044 2045 //--- non-public methods ---------------------------------------- 2046 2047 /** 2048 * Start the eviction thread or service, or when 2049 * <code>delay</code> is non-positive, stop it 2050 * if it is already running. 2051 * 2052 * @param delay milliseconds between evictor runs. 2053 */ 2054 protected synchronized void startEvictor(long delay) { 2055 if (null != _evictor) { 2056 EvictionTimer.cancel(_evictor); 2057 _evictor = null; 2058 } 2059 if (delay > 0) { 2060 _evictor = new Evictor(); 2061 EvictionTimer.schedule(_evictor, delay, delay); 2062 } 2063 } 2064 2065 /** 2066 * Returns pool info including {@link #getNumActive()}, {@link #getNumIdle()} 2067 * and currently defined keys. 2068 * 2069 * @return string containing debug information 2070 */ 2071 synchronized String debugInfo() { 2072 StringBuffer buf = new StringBuffer(); 2073 buf.append("Active: ").append(getNumActive()).append("\n"); 2074 buf.append("Idle: ").append(getNumIdle()).append("\n"); 2075 Iterator it = _poolMap.keySet().iterator(); 2076 while (it.hasNext()) { 2077 Object key = it.next(); 2078 buf.append("\t").append(key).append(" ").append(_poolMap.get(key)).append("\n"); 2079 } 2080 return buf.toString(); 2081 } 2082 2083 /** 2084 * Returns the number of tests to be performed in an Evictor run, 2085 * based on the current values of <code>_numTestsPerEvictionRun</code> 2086 * and <code>_totalIdle</code>. 2087 * 2088 * @see #setNumTestsPerEvictionRun 2089 * @return the number of tests for the Evictor to run 2090 */ 2091 private synchronized int getNumTests() { 2092 if (_numTestsPerEvictionRun >= 0) { 2093 return Math.min(_numTestsPerEvictionRun, _totalIdle); 2094 } else { 2095 return(int)(Math.ceil(_totalIdle/Math.abs((double)_numTestsPerEvictionRun))); 2096 } 2097 } 2098 2099 /** 2100 * This returns the number of objects to create during the pool 2101 * sustain cycle. This will ensure that the minimum number of idle 2102 * instances is maintained without going past the maxActive value. 2103 * 2104 * @param pool the ObjectPool to calculate the deficit for 2105 * @param incrementInternal - Should the count of objects currently under 2106 * some form of internal processing be 2107 * incremented? 2108 * @return The number of objects to be created 2109 */ 2110 private synchronized int calculateDefecit(ObjectQueue pool, 2111 boolean incrementInternal) { 2112 int objectDefecit = 0; 2113 2114 //Calculate no of objects needed to be created, in order to have 2115 //the number of pooled objects < maxActive(); 2116 objectDefecit = getMinIdle() - pool.queue.size(); 2117 if (getMaxActive() > 0) { 2118 int growLimit = Math.max(0, getMaxActive() - pool.activeCount - pool.queue.size() - pool.internalProcessingCount); 2119 objectDefecit = Math.min(objectDefecit, growLimit); 2120 } 2121 2122 // Take the maxTotal limit into account 2123 if (getMaxTotal() > 0) { 2124 int growLimit = Math.max(0, getMaxTotal() - getNumActive() - getNumIdle() - _totalInternalProcessing); 2125 objectDefecit = Math.min(objectDefecit, growLimit); 2126 } 2127 2128 if (incrementInternal && objectDefecit > 0) { 2129 pool.incrementInternalProcessingCount(); 2130 } 2131 return objectDefecit; 2132 } 2133 2134 //--- inner classes ---------------------------------------------- 2135 2136 /** 2137 * A "struct" that keeps additional information about the actual queue of pooled objects. 2138 */ 2139 private class ObjectQueue { 2140 /** Number of instances checked out to clients from this queue */ 2141 private int activeCount = 0; 2142 2143 /** Idle instance queue */ 2144 private final CursorableLinkedList queue = new CursorableLinkedList(); 2145 2146 /** Number of instances in process of being created */ 2147 private int internalProcessingCount = 0; 2148 2149 /** Increment the active count for this queue */ 2150 void incrementActiveCount() { 2151 synchronized (GenericKeyedObjectPool.this) { 2152 _totalActive++; 2153 } 2154 activeCount++; 2155 } 2156 2157 /** Decrement the active count for this queue */ 2158 void decrementActiveCount() { 2159 synchronized (GenericKeyedObjectPool.this) { 2160 _totalActive--; 2161 } 2162 if (activeCount > 0) { 2163 activeCount--; 2164 } 2165 } 2166 2167 /** Record the fact that one more instance is queued for creation */ 2168 void incrementInternalProcessingCount() { 2169 synchronized (GenericKeyedObjectPool.this) { 2170 _totalInternalProcessing++; 2171 } 2172 internalProcessingCount++; 2173 } 2174 2175 /** Decrement the number of instances in process of being created */ 2176 void decrementInternalProcessingCount() { 2177 synchronized (GenericKeyedObjectPool.this) { 2178 _totalInternalProcessing--; 2179 } 2180 internalProcessingCount--; 2181 } 2182 } 2183 2184 /** 2185 * A simple "struct" encapsulating an object instance and a timestamp. 2186 * 2187 * Implements Comparable, objects are sorted from old to new. 2188 * 2189 * This is also used by {@link GenericObjectPool}. 2190 */ 2191 static class ObjectTimestampPair implements Comparable { 2192 2193 /** Object instance */ 2194 Object value; 2195 2196 /** timestamp */ 2197 long tstamp; 2198 2199 /** 2200 * Create a new ObjectTimestampPair using the given object and the current system time. 2201 * @param val object instance 2202 */ 2203 ObjectTimestampPair(Object val) { 2204 this(val, System.currentTimeMillis()); 2205 } 2206 2207 /** 2208 * Create a new ObjectTimeStampPair using the given object and timestamp value. 2209 * @param val object instance 2210 * @param time long representation of timestamp 2211 */ 2212 ObjectTimestampPair(Object val, long time) { 2213 value = val; 2214 tstamp = time; 2215 } 2216 2217 /** 2218 * Returns a string representation. 2219 * 2220 * @return String representing this ObjectTimestampPair 2221 */ 2222 public String toString() { 2223 return value + ";" + tstamp; 2224 } 2225 2226 /** 2227 * Compares this to another object by casting the argument to an 2228 * ObjectTimestampPair. 2229 * 2230 * @param obj object to cmpare 2231 * @return result of comparison 2232 */ 2233 public int compareTo(Object obj) { 2234 return compareTo((ObjectTimestampPair) obj); 2235 } 2236 2237 /** 2238 * Compares this to another ObjectTimestampPair, using the timestamp as basis for comparison. 2239 * Implementation is consistent with equals. 2240 * 2241 * @param other object to compare 2242 * @return result of comparison 2243 */ 2244 public int compareTo(ObjectTimestampPair other) { 2245 final long tstampdiff = this.tstamp - other.tstamp; 2246 if (tstampdiff == 0) { 2247 // make sure the natural ordering is consistent with equals 2248 // see java.lang.Comparable Javadocs 2249 return System.identityHashCode(this) - System.identityHashCode(other); 2250 } else { 2251 // handle int overflow 2252 return (int)Math.min(Math.max(tstampdiff, Integer.MIN_VALUE), Integer.MAX_VALUE); 2253 } 2254 } 2255 } 2256 2257 /** 2258 * The idle object evictor {@link TimerTask}. 2259 * @see GenericKeyedObjectPool#setTimeBetweenEvictionRunsMillis 2260 */ 2261 private class Evictor extends TimerTask { 2262 /** 2263 * Run pool maintenance. Evict objects qualifying for eviction and then 2264 * invoke {@link GenericKeyedObjectPool#ensureMinIdle()}. 2265 */ 2266 public void run() { 2267 //Evict from the pool 2268 try { 2269 evict(); 2270 } catch(Exception e) { 2271 // ignored 2272 } catch(OutOfMemoryError oome) { 2273 // Log problem but give evictor thread a chance to continue in 2274 // case error is recoverable 2275 oome.printStackTrace(System.err); 2276 } 2277 //Re-create idle instances. 2278 try { 2279 ensureMinIdle(); 2280 } catch (Exception e) { 2281 // ignored 2282 } 2283 } 2284 } 2285 2286 /** 2287 * A simple "struct" encapsulating the 2288 * configuration information for a <code>GenericKeyedObjectPool</code>. 2289 * @see GenericKeyedObjectPool#GenericKeyedObjectPool(KeyedPoolableObjectFactory,GenericKeyedObjectPool.Config) 2290 * @see GenericKeyedObjectPool#setConfig 2291 */ 2292 public static class Config { 2293 /** 2294 * @see GenericKeyedObjectPool#setMaxIdle 2295 */ 2296 public int maxIdle = GenericKeyedObjectPool.DEFAULT_MAX_IDLE; 2297 /** 2298 * @see GenericKeyedObjectPool#setMaxActive 2299 */ 2300 public int maxActive = GenericKeyedObjectPool.DEFAULT_MAX_ACTIVE; 2301 /** 2302 * @see GenericKeyedObjectPool#setMaxTotal 2303 */ 2304 public int maxTotal = GenericKeyedObjectPool.DEFAULT_MAX_TOTAL; 2305 /** 2306 * @see GenericKeyedObjectPool#setMinIdle 2307 */ 2308 public int minIdle = GenericKeyedObjectPool.DEFAULT_MIN_IDLE; 2309 /** 2310 * @see GenericKeyedObjectPool#setMaxWait 2311 */ 2312 public long maxWait = GenericKeyedObjectPool.DEFAULT_MAX_WAIT; 2313 /** 2314 * @see GenericKeyedObjectPool#setWhenExhaustedAction 2315 */ 2316 public byte whenExhaustedAction = GenericKeyedObjectPool.DEFAULT_WHEN_EXHAUSTED_ACTION; 2317 /** 2318 * @see GenericKeyedObjectPool#setTestOnBorrow 2319 */ 2320 public boolean testOnBorrow = GenericKeyedObjectPool.DEFAULT_TEST_ON_BORROW; 2321 /** 2322 * @see GenericKeyedObjectPool#setTestOnReturn 2323 */ 2324 public boolean testOnReturn = GenericKeyedObjectPool.DEFAULT_TEST_ON_RETURN; 2325 /** 2326 * @see GenericKeyedObjectPool#setTestWhileIdle 2327 */ 2328 public boolean testWhileIdle = GenericKeyedObjectPool.DEFAULT_TEST_WHILE_IDLE; 2329 /** 2330 * @see GenericKeyedObjectPool#setTimeBetweenEvictionRunsMillis 2331 */ 2332 public long timeBetweenEvictionRunsMillis = GenericKeyedObjectPool.DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS; 2333 /** 2334 * @see GenericKeyedObjectPool#setNumTestsPerEvictionRun 2335 */ 2336 public int numTestsPerEvictionRun = GenericKeyedObjectPool.DEFAULT_NUM_TESTS_PER_EVICTION_RUN; 2337 /** 2338 * @see GenericKeyedObjectPool#setMinEvictableIdleTimeMillis 2339 */ 2340 public long minEvictableIdleTimeMillis = GenericKeyedObjectPool.DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS; 2341 /** 2342 * @see GenericKeyedObjectPool#setLifo 2343 */ 2344 public boolean lifo = GenericKeyedObjectPool.DEFAULT_LIFO; 2345 } 2346 2347 /** 2348 * Latch used to control allocation order of objects to threads to ensure 2349 * fairness. That is, for each key, objects are allocated to threads in the order 2350 * that threads request objects. 2351 * 2352 * @since 1.5 2353 */ 2354 private static final class Latch { 2355 2356 /** key of associated pool */ 2357 private final Object _key; 2358 2359 /** keyed pool associated with this latch */ 2360 private ObjectQueue _pool; 2361 2362 /** holds an ObjectTimestampPair when this latch has been allocated an instance */ 2363 private ObjectTimestampPair _pair; 2364 2365 /** indicates that this latch can create an instance */ 2366 private boolean _mayCreate = false; 2367 2368 /** 2369 * Create a latch with the given key 2370 * @param key key of the pool associated with this latch 2371 */ 2372 private Latch(Object key) { 2373 _key = key; 2374 } 2375 2376 /** 2377 * Retuns the key of the associated pool 2378 * @return associated pool key 2379 */ 2380 private synchronized Object getkey() { 2381 return _key; 2382 } 2383 2384 /** 2385 * Returns the pool associated with this latch 2386 * @return pool 2387 */ 2388 private synchronized ObjectQueue getPool() { 2389 return _pool; 2390 } 2391 2392 /** 2393 * Sets the pool associated with this latch 2394 * @param pool the pool 2395 */ 2396 private synchronized void setPool(ObjectQueue pool) { 2397 _pool = pool; 2398 } 2399 2400 /** 2401 * Gets the ObjectTimestampPair allocated to this latch. 2402 * Returns null if this latch does not have an instance allocated to it. 2403 * @return the associated ObjectTimestampPair 2404 */ 2405 private synchronized ObjectTimestampPair getPair() { 2406 return _pair; 2407 } 2408 2409 /** 2410 * Allocate an ObjectTimestampPair to this latch. 2411 * @param pair ObjectTimestampPair on this latch 2412 */ 2413 private synchronized void setPair(ObjectTimestampPair pair) { 2414 _pair = pair; 2415 } 2416 2417 /** 2418 * Whether or not this latch can create an instance 2419 * @return true if this latch has an instance creation permit 2420 */ 2421 private synchronized boolean mayCreate() { 2422 return _mayCreate; 2423 } 2424 2425 /** 2426 * Sets the mayCreate property 2427 * 2428 * @param mayCreate true means this latch can create an instance 2429 */ 2430 private synchronized void setMayCreate(boolean mayCreate) { 2431 _mayCreate = mayCreate; 2432 } 2433 2434 /** 2435 * Reset the latch data. Used when an allocation fails and the latch 2436 * needs to be re-added to the queue. 2437 */ 2438 private synchronized void reset() { 2439 _pair = null; 2440 _mayCreate = false; 2441 } 2442 } 2443 2444 //--- protected attributes --------------------------------------- 2445 2446 /** 2447 * The cap on the number of idle instances in the pool. 2448 * @see #setMaxIdle 2449 * @see #getMaxIdle 2450 */ 2451 private int _maxIdle = DEFAULT_MAX_IDLE; 2452 2453 /** 2454 * The minimum no of idle objects to keep in the pool. 2455 * @see #setMinIdle 2456 * @see #getMinIdle 2457 */ 2458 private int _minIdle = DEFAULT_MIN_IDLE; 2459 2460 /** 2461 * The cap on the number of active instances from the pool. 2462 * @see #setMaxActive 2463 * @see #getMaxActive 2464 */ 2465 private int _maxActive = DEFAULT_MAX_ACTIVE; 2466 2467 /** 2468 * The cap on the total number of instances from the pool if non-positive. 2469 * @see #setMaxTotal 2470 * @see #getMaxTotal 2471 */ 2472 private int _maxTotal = DEFAULT_MAX_TOTAL; 2473 2474 /** 2475 * The maximum amount of time (in millis) the 2476 * {@link #borrowObject} method should block before throwing 2477 * an exception when the pool is exhausted and the 2478 * {@link #getWhenExhaustedAction "when exhausted" action} is 2479 * {@link #WHEN_EXHAUSTED_BLOCK}. 2480 * 2481 * When less than or equal to 0, the {@link #borrowObject} method 2482 * may block indefinitely. 2483 * 2484 * @see #setMaxWait 2485 * @see #getMaxWait 2486 * @see #WHEN_EXHAUSTED_BLOCK 2487 * @see #setWhenExhaustedAction 2488 * @see #getWhenExhaustedAction 2489 */ 2490 private long _maxWait = DEFAULT_MAX_WAIT; 2491 2492 /** 2493 * The action to take when the {@link #borrowObject} method 2494 * is invoked when the pool is exhausted (the maximum number 2495 * of "active" objects has been reached). 2496 * 2497 * @see #WHEN_EXHAUSTED_BLOCK 2498 * @see #WHEN_EXHAUSTED_FAIL 2499 * @see #WHEN_EXHAUSTED_GROW 2500 * @see #DEFAULT_WHEN_EXHAUSTED_ACTION 2501 * @see #setWhenExhaustedAction 2502 * @see #getWhenExhaustedAction 2503 */ 2504 private byte _whenExhaustedAction = DEFAULT_WHEN_EXHAUSTED_ACTION; 2505 2506 /** 2507 * When <code>true</code>, objects will be 2508 * {@link org.apache.commons.pool.PoolableObjectFactory#validateObject validated} 2509 * before being returned by the {@link #borrowObject} 2510 * method. If the object fails to validate, 2511 * it will be dropped from the pool, and we will attempt 2512 * to borrow another. 2513 * 2514 * @see #setTestOnBorrow 2515 * @see #getTestOnBorrow 2516 */ 2517 private volatile boolean _testOnBorrow = DEFAULT_TEST_ON_BORROW; 2518 2519 /** 2520 * When <code>true</code>, objects will be 2521 * {@link org.apache.commons.pool.PoolableObjectFactory#validateObject validated} 2522 * before being returned to the pool within the 2523 * {@link #returnObject}. 2524 * 2525 * @see #getTestOnReturn 2526 * @see #setTestOnReturn 2527 */ 2528 private volatile boolean _testOnReturn = DEFAULT_TEST_ON_RETURN; 2529 2530 /** 2531 * When <code>true</code>, objects will be 2532 * {@link org.apache.commons.pool.PoolableObjectFactory#validateObject validated} 2533 * by the idle object evictor (if any). If an object 2534 * fails to validate, it will be dropped from the pool. 2535 * 2536 * @see #setTestWhileIdle 2537 * @see #getTestWhileIdle 2538 * @see #getTimeBetweenEvictionRunsMillis 2539 * @see #setTimeBetweenEvictionRunsMillis 2540 */ 2541 private boolean _testWhileIdle = DEFAULT_TEST_WHILE_IDLE; 2542 2543 /** 2544 * The number of milliseconds to sleep between runs of the 2545 * idle object evictor thread. 2546 * When non-positive, no idle object evictor thread will be 2547 * run. 2548 * 2549 * @see #setTimeBetweenEvictionRunsMillis 2550 * @see #getTimeBetweenEvictionRunsMillis 2551 */ 2552 private long _timeBetweenEvictionRunsMillis = DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS; 2553 2554 /** 2555 * The number of objects to examine during each run of the 2556 * idle object evictor thread (if any). 2557 * <p> 2558 * When a negative value is supplied, <code>ceil({@link #getNumIdle})/abs({@link #getNumTestsPerEvictionRun})</code> 2559 * tests will be run. I.e., when the value is <code>-n</code>, roughly one <code>n</code>th of the 2560 * idle objects will be tested per run. 2561 * 2562 * @see #setNumTestsPerEvictionRun 2563 * @see #getNumTestsPerEvictionRun 2564 * @see #getTimeBetweenEvictionRunsMillis 2565 * @see #setTimeBetweenEvictionRunsMillis 2566 */ 2567 private int _numTestsPerEvictionRun = DEFAULT_NUM_TESTS_PER_EVICTION_RUN; 2568 2569 /** 2570 * The minimum amount of time an object may sit idle in the pool 2571 * before it is eligible for eviction by the idle object evictor 2572 * (if any). 2573 * When non-positive, no objects will be evicted from the pool 2574 * due to idle time alone. 2575 * 2576 * @see #setMinEvictableIdleTimeMillis 2577 * @see #getMinEvictableIdleTimeMillis 2578 * @see #getTimeBetweenEvictionRunsMillis 2579 * @see #setTimeBetweenEvictionRunsMillis 2580 */ 2581 private long _minEvictableIdleTimeMillis = DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS; 2582 2583 /** My hash of pools (ObjectQueue). */ 2584 private Map _poolMap = null; 2585 2586 /** The total number of active instances. */ 2587 private int _totalActive = 0; 2588 2589 /** The total number of idle instances. */ 2590 private int _totalIdle = 0; 2591 2592 /** 2593 * The number of objects subject to some form of internal processing 2594 * (usually creation or destruction) that should be included in the total 2595 * number of objects but are neither active nor idle. 2596 */ 2597 private int _totalInternalProcessing = 0; 2598 2599 /** My {@link KeyedPoolableObjectFactory}. */ 2600 private KeyedPoolableObjectFactory _factory = null; 2601 2602 /** 2603 * My idle object eviction {@link TimerTask}, if any. 2604 */ 2605 private Evictor _evictor = null; 2606 2607 /** 2608 * A cursorable list of my pools. 2609 * @see GenericKeyedObjectPool.Evictor#run 2610 */ 2611 private CursorableLinkedList _poolList = null; 2612 2613 /** Eviction cursor (over instances within-key) */ 2614 private CursorableLinkedList.Cursor _evictionCursor = null; 2615 2616 /** Eviction cursor (over keys) */ 2617 private CursorableLinkedList.Cursor _evictionKeyCursor = null; 2618 2619 /** Whether or not the pools behave as LIFO queues (last in first out) */ 2620 private boolean _lifo = DEFAULT_LIFO; 2621 2622 /** 2623 * Used to track the order in which threads call {@link #borrowObject()} so 2624 * that objects can be allocated in the order in which the threads requested 2625 * them. 2626 */ 2627 private LinkedList _allocationQueue = new LinkedList(); 2628 2629 }