/*
 * Copyright 2009 Ralf Joachim, Ahmad Hassan
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.castor.cpa.persistence.sql.query.expression;

import org.castor.cpa.persistence.sql.query.Visitor;

/**
 * Class for NEXTVAL sql function.
 * 
 * @author <a href="mailto:ahmad DOT hassan AT gmail DOT com">Ahmad Hassan</a>
 * @author <a href="mailto:ralf DOT joachim AT syscon DOT eu">Ralf Joachim</a>
 * @version $Revision$ $Date: 2006-04-25 15:08:23 -0600 (Tue, 25 Apr 2006) $
 */
public final class NextVal extends Function {
    //-----------------------------------------------------------------------------------    

    /** Name of the sequence to get next value of. */
    private final String _seqName;
    
    //-----------------------------------------------------------------------------------    

    /**
     * Constructor. 
     * 
     * @param seqName Name of the sequence.
     */
    public NextVal(final String seqName) {
        if (seqName == null) { throw new NullPointerException(); }
        _seqName = seqName;
    }
    
    //-----------------------------------------------------------------------------------    

    /** Method to get seqName currently set.
     * 
     * @return SeqName currently set.
     */
    public String getSeqName () { return _seqName; } 

    //-----------------------------------------------------------------------------------    

    /**
     * {@inheritDoc}
     */
    public void accept (final Visitor visitor) { visitor.visit(this); }

    //-----------------------------------------------------------------------------------

    /** 
     * Method constructing query string.
     * 
     * @return Constructed query string.
     */
    public String toString() {
        StringBuffer sb = new StringBuffer();
        sb.append(_seqName + ".nextval");

        return sb.toString();
    }

    //-----------------------------------------------------------------------------------    
}