/*
|
* CDDL HEADER START
|
*
|
* The contents of this file are subject to the terms of the
|
* Common Development and Distribution License, Version 1.0 only
|
* (the "License"). You may not use this file except in compliance
|
* with the License.
|
*
|
* You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
|
* or http://forgerock.org/license/CDDLv1.0.html.
|
* See the License for the specific language governing permissions
|
* and limitations under the License.
|
*
|
* When distributing Covered Code, include this CDDL HEADER in each
|
* file and include the License file at legal-notices/CDDLv1_0.txt.
|
* If applicable, add the following below this CDDL HEADER, with the
|
* fields enclosed by brackets "[]" replaced with your own identifying
|
* information:
|
* Portions Copyright [yyyy] [name of copyright owner]
|
*
|
* CDDL HEADER END
|
*
|
*
|
* Copyright 2014 ForgeRock AS.
|
*/
|
package org.opends.server.replication.server.changelog.file;
|
|
import java.io.File;
|
import java.io.RandomAccessFile;
|
|
import org.opends.server.replication.server.changelog.api.ChangelogException;
|
import org.opends.server.util.StaticUtils;
|
|
import static org.opends.messages.ReplicationMessages.*;
|
|
/**
|
* A Pool of readers to a log file.
|
|
*
|
* @param <K>
|
* Type of the key of a record, which must be comparable.
|
* @param <V>
|
* Type of the value of a record.
|
*/
|
// TODO : implement a real pool - reusing readers instead of opening-closing them each time
|
class LogReaderPool<K extends Comparable<K>, V>
|
{
|
/** The file to read. */
|
private final File file;
|
|
private final RecordParser<K, V> parser;
|
|
/**
|
* Creates a pool of readers for provided file.
|
*
|
* @param file
|
* The file to read.
|
* @param parser
|
* The parser to decode the records read.
|
*/
|
LogReaderPool(File file, RecordParser<K, V> parser)
|
{
|
this.file = file;
|
this.parser = parser;
|
}
|
|
/**
|
* Returns a random access reader on the provided file.
|
* <p>
|
* The acquired reader must be released with the {@code release()}
|
* method.
|
*
|
* @return a random access reader
|
* @throws ChangelogException
|
* If the file can't be found or read.
|
*/
|
BlockLogReader<K, V> get() throws ChangelogException
|
{
|
return getReader(file);
|
}
|
|
/**
|
* Release the provided reader.
|
* <p>
|
* Once released, this reader must not be used any more.
|
*
|
* @param reader
|
* The random access reader to a file previously acquired with this
|
* pool.
|
*/
|
void release(BlockLogReader<K, V> reader)
|
{
|
StaticUtils.close(reader);
|
}
|
|
/** Returns a random access file to read this log. */
|
private BlockLogReader<K, V> getReader(File file) throws ChangelogException
|
{
|
try
|
{
|
return BlockLogReader.newReader(file, new RandomAccessFile(file, "r"), parser) ;
|
}
|
catch (Exception e)
|
{
|
throw new ChangelogException(ERR_CHANGELOG_UNABLE_TO_OPEN_READER_ON_LOG_FILE.get(file.getPath()), e);
|
}
|
}
|
|
/**
|
* Shutdown this pool, releasing all files handles opened
|
* on the file.
|
*/
|
void shutdown()
|
{
|
// Nothing to do yet as no file handle is kept opened.
|
}
|
|
}
|
