001: /*
002: * $Id: AxionSequencesMetaTableUpdater.java,v 1.1 2004/08/13 02:01:13 ahimanikya Exp $
003: * =======================================================================
004: * Copyright (c) 2002 Axion Development Team. All rights reserved.
005: *
006: * Redistribution and use in source and binary forms, with or without
007: * modification, are permitted provided that the following conditions
008: * are met:
009: *
010: * 1. Redistributions of source code must retain the above
011: * copyright notice, this list of conditions and the following
012: * disclaimer.
013: *
014: * 2. Redistributions in binary form must reproduce the above copyright
015: * notice, this list of conditions and the following disclaimer in
016: * the documentation and/or other materials provided with the
017: * distribution.
018: *
019: * 3. The names "Tigris", "Axion", nor the names of its contributors may
020: * not be used to endorse or promote products derived from this
021: * software without specific prior written permission.
022: *
023: * 4. Products derived from this software may not be called "Axion", nor
024: * may "Tigris" or "Axion" appear in their names without specific prior
025: * written permission.
026: *
027: * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
028: * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
029: * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
030: * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
031: * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
032: * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
033: * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
034: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
035: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
036: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
037: * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
038: * =======================================================================
039: */
040:
041: package org.axiondb.engine.metaupdaters;
042:
043: import org.apache.commons.logging.Log;
044: import org.apache.commons.logging.LogFactory;
045: import org.axiondb.AxionException;
046: import org.axiondb.ColumnIdentifier;
047: import org.axiondb.Database;
048: import org.axiondb.Literal;
049: import org.axiondb.Selectable;
050: import org.axiondb.TableIdentifier;
051: import org.axiondb.engine.commands.UpdateCommand;
052: import org.axiondb.engine.rows.SimpleRow;
053: import org.axiondb.event.BaseDatabaseModificationListener;
054: import org.axiondb.event.DatabaseModificationListener;
055: import org.axiondb.event.DatabaseSequenceEvent;
056: import org.axiondb.event.SequenceModificationListener;
057: import org.axiondb.functions.FunctionIdentifier;
058:
059: /**
060: * Updates the <code>AXION_SEQUENCES</code> meta table
061: *
062: * @version $Revision: 1.1 $ $Date: 2004/08/13 02:01:13 $
063: * @author Chuck Burdick
064: * @author Rodney Waldhoff
065: */
066: public class AxionSequencesMetaTableUpdater extends
067: BaseDatabaseModificationListener implements
068: DatabaseModificationListener, SequenceModificationListener {
069: private static Log _log = LogFactory
070: .getLog(AxionSequencesMetaTableUpdater.class);
071: private Database _db = null;
072:
073: public AxionSequencesMetaTableUpdater(Database db) {
074: _db = db;
075: }
076:
077: public void sequenceAdded(DatabaseSequenceEvent e) {
078: SimpleRow row = new SimpleRow(2);
079: row.set(0, e.getName());
080: row.set(1, e.getValue());
081: try {
082: _db.getTable("AXION_SEQUENCES").addRow(row);
083: } catch (AxionException ex) {
084: _log.error("Unable to mention sequence in system tables",
085: ex);
086: }
087: }
088:
089: public void sequenceIncremented(DatabaseSequenceEvent e) {
090: ColumnIdentifier col = new ColumnIdentifier("SEQUENCE_NAME");
091: Literal lit = new Literal(e.getName());
092: UpdateCommand cmd = new UpdateCommand();
093: cmd.setTable(new TableIdentifier("AXION_SEQUENCES"));
094: cmd.setWhere(makeEqualFunction(col, lit));
095: cmd.addColumn(new ColumnIdentifier("SEQUENCE_VALUE"));
096: cmd.addValue(new Literal(e.getValue()));
097: try {
098: cmd.executeUpdate(_db);
099: } catch (AxionException ex) {
100: _log.error(
101: "Unable to update sequence value in system tables",
102: ex);
103: }
104: }
105:
106: private FunctionIdentifier makeEqualFunction(Selectable left,
107: Selectable right) {
108: FunctionIdentifier function = new FunctionIdentifier("=");
109: function.addArgument(left);
110: function.addArgument(right);
111: return function;
112: }
113: }
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