| /** |
| * JDBM LICENSE v1.00 |
| * |
| * Redistribution and use of this software and associated documentation |
| * ("Software"), with or without modification, are permitted provided |
| * that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain copyright |
| * statements and notices. Redistributions must also contain a |
| * copy of this document. |
| * |
| * 2. Redistributions in binary form must reproduce the |
| * above copyright notice, this list of conditions and the |
| * following disclaimer in the documentation and/or other |
| * materials provided with the distribution. |
| * |
| * 3. The name "JDBM" must not be used to endorse or promote |
| * products derived from this Software without prior written |
| * permission of Cees de Groot. For written permission, |
| * please contact cg@cdegroot.com. |
| * |
| * 4. Products derived from this Software may not be called "JDBM" |
| * nor may "JDBM" appear in their names without prior written |
| * permission of Cees de Groot. |
| * |
| * 5. Due credit should be given to the JDBM Project |
| * (http://jdbm.sourceforge.net/). |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE JDBM PROJECT AND CONTRIBUTORS |
| * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT |
| * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND |
| * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL |
| * CEES DE GROOT OR ANY CONTRIBUTORS BE LIABLE FOR ANY DIRECT, |
| * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| * OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| * Copyright 2000 (C) Cees de Groot. All Rights Reserved. |
| * Contributions are Copyright (C) 2000 by their associated contributors. |
| * |
| * $Id: LogicalRowIdManager.java,v 1.3 2005/06/25 23:12:32 doomdark Exp $ |
| */ |
| |
| package jdbm.recman; |
| |
| |
| import java.io.IOException; |
| |
| import org.apache.directory.server.i18n.I18n; |
| |
| |
| /** |
| * This class manages the linked lists of logical rowid pages. |
| */ |
| final class LogicalRowIdManager |
| { |
| // our record recordFile and associated page manager |
| private RecordFile recordFile; |
| private PageManager pageManager; |
| private FreeLogicalRowIdPageManager freeman; |
| |
| |
| /** |
| * Creates a log rowid manager using the indicated record recordFile and |
| * page manager |
| */ |
| LogicalRowIdManager( PageManager pageManager ) throws IOException |
| { |
| this.recordFile = pageManager.getRecordFile(); |
| this.pageManager = pageManager; |
| this.freeman = new FreeLogicalRowIdPageManager( pageManager ); |
| } |
| |
| |
| /** |
| * Creates a new logical rowid pointing to the indicated physical |
| * id |
| */ |
| Location insert( Location loc ) throws IOException |
| { |
| // check whether there's a free rowid to reuse |
| Location retval = freeman.get(); |
| if ( retval == null ) |
| { |
| // no. This means that we bootstrap things by allocating |
| // a new translation page and freeing all the rowids on it. |
| long firstPage = pageManager.allocate( Magic.TRANSLATION_PAGE ); |
| short curOffset = TranslationPage.O_TRANS; |
| for ( int i = 0; i < TranslationPage.ELEMS_PER_PAGE; i++ ) |
| { |
| freeman.put( new Location( firstPage, curOffset ) ); |
| curOffset += PhysicalRowId.SIZE; |
| } |
| retval = freeman.get(); |
| if ( retval == null ) |
| { |
| throw new Error( I18n.err( I18n.ERR_545 ) ); |
| } |
| } |
| // write the translation. |
| update( retval, loc ); |
| return retval; |
| } |
| |
| |
| /** |
| * Releases the indicated logical rowid. |
| */ |
| void delete( Location rowid ) throws IOException |
| { |
| |
| freeman.put( rowid ); |
| } |
| |
| |
| /** |
| * Updates the mapping |
| * |
| * @param rowid The logical rowid |
| * @param loc The physical rowid |
| */ |
| void update( Location rowid, Location loc ) throws IOException |
| { |
| |
| TranslationPage xlatPage = TranslationPage.getTranslationPageView( recordFile.get( rowid.getBlock() ) ); |
| PhysicalRowId physid = xlatPage.get( rowid.getOffset() ); |
| physid.setBlock( loc.getBlock() ); |
| physid.setOffset( loc.getOffset() ); |
| recordFile.release( rowid.getBlock(), true ); |
| } |
| |
| |
| /** |
| * Returns a mapping |
| * |
| * @param rowid The logical rowid |
| * @return The physical rowid |
| */ |
| Location fetch( Location rowid ) throws IOException |
| { |
| |
| TranslationPage xlatPage = TranslationPage.getTranslationPageView( recordFile.get( rowid.getBlock() ) ); |
| try |
| { |
| Location retval = new Location( xlatPage.get( rowid.getOffset() ) ); |
| return retval; |
| } |
| finally |
| { |
| recordFile.release( rowid.getBlock(), false ); |
| } |
| } |
| |
| } |