/*
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 1999-2002 The Apache Software Foundation.  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 end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:  
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Xerces" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written 
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``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 THE APACHE SOFTWARE FOUNDATION OR
 * ITS 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation and was
 * originally based on software copyright (c) 1999, International
 * Business Machines, Inc., http://www.apache.org.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package org.apache.xerces.impl.xs.models;

import org.apache.xerces.impl.dtd.models.CMNode;
import org.apache.xerces.impl.dtd.models.CMStateSet;
import org.apache.xerces.impl.xs.XSParticleDecl;

/**
 *
 * Content model Uni-Op node.
 *
 * @author Neil Graham, IBM
 * @version $$
 */
public class XSCMUniOp extends CMNode {
    // -------------------------------------------------------------------
    //  Constructors
    // -------------------------------------------------------------------
    public XSCMUniOp(int type, CMNode childNode) {
        super(type);

        // Insure that its one of the types we require
        if ((type() != XSParticleDecl.PARTICLE_ZERO_OR_ONE)
        &&  (type() != XSParticleDecl.PARTICLE_ZERO_OR_MORE)
        &&  (type() != XSParticleDecl.PARTICLE_ONE_OR_MORE)) {
            throw new RuntimeException("ImplementationMessages.VAL_UST");
        }

        // Store the node and init any data that needs it
        fChild = childNode;
    }


    // -------------------------------------------------------------------
    //  Package, final methods
    // -------------------------------------------------------------------
    final CMNode getChild() {
        return fChild;
    }


    // -------------------------------------------------------------------
    //  Package, inherited methods
    // -------------------------------------------------------------------
    public boolean isNullable() {
        //
        //  For debugging purposes, make sure we got rid of all non '*'
        //  repetitions. Otherwise, '*' style nodes are always nullable.
        //
        if (type() == XSParticleDecl.PARTICLE_ONE_OR_MORE)
	        return fChild.isNullable();
	    else
	        return true;
    }


    // -------------------------------------------------------------------
    //  Protected, inherited methods
    // -------------------------------------------------------------------
    protected void calcFirstPos(CMStateSet toSet) {
        // Its just based on our child node's first pos
        toSet.setTo(fChild.firstPos());
    }

    protected void calcLastPos(CMStateSet toSet) {
        // Its just based on our child node's last pos
        toSet.setTo(fChild.lastPos());
    }


    // -------------------------------------------------------------------
    //  Private data members
    //
    //  fChild
    //      This is the reference to the one child that we have for this
    //      unary operation.
    // -------------------------------------------------------------------
    private CMNode  fChild;
} // XSCMUniOp

