/*
The MIT License

Copyright (c) 2008 Tahseen Ur Rehman, Javid Jamae

http://code.google.com/p/radixtree/

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

package ds.tree;

/**
 * The visitor interface that is used by {@link RadixTreeImpl} for perfroming
 * task on a searched node.
 *
 * @author Tahseen Ur Rehman (tahseen.ur.rehman {at.spam.me.not} gmail.com)
 * @author Javid Jamae
 * @author Dennis Heidsiek
 * @param <T,R>
 */
public interface Visitor<T, R> {
    /**
     * This method gets called by {@link RadixTreeImpl#visit(String, Visitor) visit}
     * when it finds a node matching the key given to it.
     *
     * @param key The key that matched the node
     * @param parent The parent of the node being visited
     * @param node The node that is being visited
     */
    public void visit(String key, RadixTreeNode<T> parent, RadixTreeNode<T> node);

    /**
     * The visitor can store any type of result object, depending on the context of
     * what it is being used for.
     *
     * @return The result captured by the visitor.
     */
    public R getResult();
}