/* * Production.java * * This work is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published * by the Free Software Foundation; either version 2 of the License, * or (at your option) any later version. * * This work is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 * USA * * As a special exception, the copyright holders of this library give * you permission to link this library with independent modules to * produce an executable, regardless of the license terms of these * independent modules, and to copy and distribute the resulting * executable under terms of your choice, provided that you also meet, * for each linked independent module, the terms and conditions of the * license of that module. An independent module is a module which is * not derived from or based on this library. If you modify this * library, you may extend this exception to your version of the * library, but you are not obligated to do so. If you do not wish to * do so, delete this exception statement from your version. * * Copyright (c) 2003 Per Cederberg. All rights reserved. */package net.percederberg.grammatica.parser;import java.util.ArrayList;/** * A production node. This class represents a grammar production (i.e. * a list of child nodes) in a parse tree. The productions are created  * by a parser, that adds children a according to a set of production * patterns (i.e. grammar rules). * * @author   Per Cederberg, <per at percederberg dot net> * @version  1.1 */public class Production extends Node {    /**     * The production pattern used for this production.     */    private ProductionPattern pattern;    /**     * The child nodes.     */    private ArrayList children;    /**     * Creates a new production node.     *      * @param pattern        the production pattern     */    public Production(ProductionPattern pattern) {        this.pattern = pattern;        this.children = new ArrayList();    }    /**     * Checks if this node is hidden, i.e. if it should not be visible     * outside the parser.     *      * @return true if the node should be hidden, or     *         false otherwise     */    boolean isHidden() {        return pattern.isSyntetic();    }    /**     * Returns the production pattern for this production.     *      * @return the production pattern     */    public ProductionPattern getPattern() {        return pattern;    }    /**     * Returns the production (pattern) id. This value is set as a      * unique identifier when creating the production pattern to      * simplify later identification.     *      * @return the production id     */    public int getId() {        return pattern.getId();        }        /**     * Returns the production node name.     *      * @return the production node name     */    public String getName() {        return pattern.getName();    }    /**     * Returns the number of child nodes.     *      * @return the number of child nodes     */    public int getChildCount() {        return children.size();    }    /**     * Returns the child node with the specified index.     *      * @param index          the child index, 0 <= index < count     *      * @return the child node found, or      *         null if index out of bounds     */    public Node getChildAt(int index) {        if (index < 0 || index >= children.size()) {            return null;         } else {            return (Node) children.get(index);        }    }        /**     * Adds a child node. The node will be added last in the list of     * children.     *      * @param child          the child node to add     */    public void addChild(Node child) {        if (child != null) {            child.setParent(this);            children.add(child);        }    }    /**     * Returns a string representation of this production.     *      * @return a string representation of this production     */    public String toString() {        StringBuffer  buffer = new StringBuffer();        buffer.append(pattern.getName());        buffer.append('(');        buffer.append(pattern.getId());        buffer.append(')');                return buffer.toString();            }}