001    /*
002     * JBoss, Home of Professional Open Source.
003     * Copyright 2008, Red Hat Middleware LLC, and individual contributors
004     * as indicated by the @author tags. See the copyright.txt file in the
005     * distribution for a full listing of individual contributors. 
006     *
007     * This is free software; you can redistribute it and/or modify it
008     * under the terms of the GNU Lesser General Public License as
009     * published by the Free Software Foundation; either version 2.1 of
010     * the License, or (at your option) any later version.
011     *
012     * This software is distributed in the hope that it will be useful,
013     * but WITHOUT ANY WARRANTY; without even the implied warranty of
014     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015     * Lesser General Public License for more details.
016     *
017     * You should have received a copy of the GNU Lesser General Public
018     * License along with this software; if not, write to the Free
019     * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
020     * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
021     */
022    package org.jboss.dna.graph;
023    
024    import net.jcip.annotations.Immutable;
025    import org.jboss.dna.graph.properties.Path;
026    
027    /**
028     * A subgraph returned by the {@link Graph}, containing the nodes in the subgraph as well as the properties and children for each
029     * of those nodes. The {@link #iterator()} method may be used to walk the nodes in the subgraph in a pre-order traversal.
030     * <p>
031     * Since this subgraph has a single {@link #getLocation() node that is the top of the subgraph}, the methods that take a String
032     * path or {@link Path path object} will accept absolute or relative paths.
033     * </p>
034     * 
035     * @author Randall Hauch
036     */
037    @Immutable
038    public interface Subgraph extends Results {
039    
040        /**
041         * Get the location of the node.
042         * 
043         * @return the node's location
044         */
045        Location getLocation();
046    
047        /**
048         * Get the maximum depth requested for this subgraph. The actual subgraph may not be as deep, but will never be deeper than
049         * this value.
050         * 
051         * @return the maximum depth requested; always positive
052         */
053        int getMaximumDepth();
054    
055        /**
056         * Get the node that is at the {@link #getLocation() root} of the subgraph.
057         * 
058         * @return the root node in the subgraph
059         */
060        Node getRoot();
061    }