createsequencecommand.java

开源的axion的数据库代码

/*
 * $Id: CreateSequenceCommand.java,v 1.10 2002/12/16 22:18:30 rwald Exp $
 * =======================================================================
 * Copyright (c) 2002 Axion Development Team.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above
 *    copyright notice, this list of conditions and the following
 *    disclaimer.
 *
 * 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 names "Tigris", "Axion", nor the names of its contributors may
 *    not be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * 4. Products derived from this software may not be called "Axion", nor
 *    may "Tigris" or "Axion" appear in their names without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS 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 THE COPYRIGHT
 * OWNER OR 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.
 * =======================================================================
 */


package org.axiondb.engine.commands;

import org.axiondb.AxionException;
import org.axiondb.Database;
import org.axiondb.Sequence;
import org.axiondb.jdbc.AxionResultSet;

/**
 * A <code>CREATE SEQUENCE</code> command.
 * 
 * @version $Revision: 1.10 $ $Date: 2002/12/16 22:18:30 $
 * @author Chuck Burdick
 */
public class CreateSequenceCommand extends BaseAxionCommand {
    public CreateSequenceCommand() {
        this(null, 0);
    }

    public CreateSequenceCommand(String sequenceName) {
        this(sequenceName, 0);
    }

    public CreateSequenceCommand(String sequenceName, int startVal) {
        _sequenceName = sequenceName;
        _startVal = startVal;
    }    

    public void setName(String name) {
        _sequenceName = name;
    }

    public String getName() {
        return _sequenceName;
    }

    public void setStartValue(String value) {
        _startVal = Integer.parseInt(value);
    }

    public void setStartValue(int value) {
        _startVal = value;
    }

    public int getStartValue() {
        return _startVal;
    }

    public boolean execute(org.axiondb.Database db) throws AxionException {
        assertNotReadOnly(db);
        Sequence seq = new Sequence(getName(), getStartValue());
        db.createSequence(seq);
        return false;
    }

    /** Unsupported */
    public AxionResultSet executeQuery(Database database) throws AxionException  {
        throw new UnsupportedOperationException("Use execute.");
    }

    public int executeUpdate(Database database) throws AxionException  {
        execute(database);
        return 0;
    }

    public String toString() {
        StringBuffer buf = new StringBuffer();
        buf.append("CREATE SEQUENCE ");
        buf.append(_sequenceName);
        buf.append("STARTS WITH ");
        buf.append(_startVal);
        return buf.toString();
    }

    private String _sequenceName = null;
    private int _startVal = 0;
}