proofstructure.java

Mandarax是一个规则引擎的纯Java实现。它支持多类型的事实和基于反映的规则

/*
 * Copyright (C) 1999-2004 <A href="http://www-ist.massey.ac.nz/JBDietrich" target="_top">Jens Dietrich</a>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package org.mandarax.examples.family;


import java.util.List;
import java.util.Vector;

import javax.swing.tree.TreeModel;
import javax.swing.tree.TreePath;

import org.mandarax.kernel.DerivationNode;

/**
 * Tree model for derivations.
 * @author <A href="http://www-ist.massey.ac.nz/JBDietrich" target="_top">Jens Dietrich</A>
 * @version 3.4 <7 March 05>
 * @since 1.2
 */
class ProofStructure implements TreeModel {

    private DerivationNode root = null;

    /**
     * Constructor.
     * @param aRoot the root node of the derivation
     */
    public ProofStructure(DerivationNode aRoot) {
        super ();

        root = aRoot;
    }

    /**
     * Not implemented method from the tree model interface.
     */
    public void addTreeModelListener(javax.swing.event.TreeModelListener l) {}

    /**
     * Get the child at the position.
     * @param parent the parent node
     * @param index the index
     * @return the child at the index
     */
    public Object getChild(Object parent, int index) {
        return getChildren (parent).get (index);
    }

    /**
     * Get the number of children.
     * @param parent a node
     * @return the number of chilkren
     */
    public int getChildCount(Object parent) {
        return getChildren (parent).size ();
    }

    /**
     * Get a list of children of the parent.
     * @return a list of children
     * @param parent the parent node
     */
    private List getChildren(Object parent) {
        try {
            DerivationNode node = (DerivationNode) parent;

            return node.getSubNodes ();
        } catch(Throwable t) {
            return new Vector ();
        }
    }

    /**
     * Get the index of a certain child.
     * @param parent the parent
     * @param child the child
     * @return the index
     *
     */
    public int getIndexOfChild(Object parent, Object child) {
        return getChildren (parent).indexOf (child);
    }

    /**
     * Get the root node.
     * @return the root node of the tree
     */
    public Object getRoot() {
        return root;
    }

    /**
     * Indicates whether the object represents a leaf.
     */
    public boolean isLeaf(Object node) {
        return false;
    }

    /**
     * Not implemented method from the tree model interface.
     */
    public void removeTreeModelListener(
            javax.swing.event.TreeModelListener l) {}

    /**
     * Not implemented method from the tree model interface.
     */
    public void valueForPathChanged(TreePath path, Object newValue) {}
}