com.sun.jts.CosTransactions.CoordinatorLogPool Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of payara-micro Show documentation
Show all versions of payara-micro Show documentation
Micro Distribution of the Payara Project
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package com.sun.jts.CosTransactions;
// Import required classes.
import java.util.*;
/**
* The CoordinatorLogPool is used as a cache for CoordinatorLog objects.
* This pool allows the re-use of these objects which are very expensive
* to instantiate.
*
* The pool is used by replacing calls to 'new CoordinatorLog()' in the
* TopCoordinator with calls to CoordinatorLogPool.getCoordinatorLog().
* The getCoordinatorLog() method attempts to return a CoordinatorLog
* from the pool. If the pool is empty it instantiates a new
* CoordinatorLog.
*
* Objects are re-used by calling CoordinatorLogPool.putCoordinatorLog()
* to return a CoordinatorLog object back to the pool. At this time a
* check is made to ensure that the internal pool size doesn't exceed a
* pre set limit. If it does, then the object is discarded and not put
* back into the pool.
*
* The pool was added to improve performance of transaction logging
*
* @version 1.00
*
* @author Arun Krishnan
*
* @see
*/
class CoordinatorLogPool {
private Stack pool;
private static final int MAXSTACKSIZE = 3;
public static CoordinatorLogPool CLPool = new CoordinatorLogPool();
public static Hashtable CLPooltable = new Hashtable();
/**
* constructor
*
*/
public CoordinatorLogPool() {
pool = new Stack();
}
/**
* get a CoordinatorLog object from the cache. Instantiate a
* new CoordinatorLog object if the cache is empty.
*
*/
public static synchronized CoordinatorLog getCoordinatorLog() {
if (Configuration.isDBLoggingEnabled() ||
Configuration.isFileLoggingDisabled())
return null;
if (CLPool.pool.empty()) {
return new CoordinatorLog();
}
else {
CoordinatorLog cl = (CoordinatorLog) CLPool.pool.pop();
return cl;
}
}
/**
* return a CoordinatorLog object to the cache. To limit the size of
* the cache a check is made to ensure that the cache doesn't
* already have more that MAXSTACKSIZE elements. If so the object
* being returned is discarded.
*
*/
public static void putCoordinatorLog(CoordinatorLog cl) {
if (CLPool.pool.size() <= MAXSTACKSIZE) {
CLPool.pool.push(cl);
}
}
// Added to support delegated recovery: multiple logs should coexist
public static synchronized CoordinatorLog getCoordinatorLog(String logPath) {
CoordinatorLogPool clpool = (CoordinatorLogPool)CLPooltable.get(logPath);
if (clpool == null) {
clpool = new CoordinatorLogPool();
CLPooltable.put(logPath,clpool);
}
if (clpool.pool.empty()) {
return new CoordinatorLog(logPath);
}
else {
return (CoordinatorLog)clpool.pool.pop();
}
}
// Added to support delegated recovery: multiple logs should coexist
public static void putCoordinatorLog(CoordinatorLog cl, String logPath) {
CoordinatorLogPool clpool = (CoordinatorLogPool)CLPooltable.get(logPath);
if (clpool == null) {
clpool = new CoordinatorLogPool();
CLPooltable.put(logPath,clpool);
}
if (clpool.pool.size() <= MAXSTACKSIZE) {
clpool.pool.push(cl);
}
}
}