001/*
002 * jPOS Project [http://jpos.org]
003 * Copyright (C) 2000-2026 jPOS Software SRL
004 *
005 * This program is free software: you can redistribute it and/or modify
006 * it under the terms of the GNU Affero General Public License as
007 * published by the Free Software Foundation, either version 3 of the
008 * License, or (at your option) any later version.
009 *
010 * This program is distributed in the hope that it will be useful,
011 * but WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
013 * GNU Affero General Public License for more details.
014 *
015 * You should have received a copy of the GNU Affero General Public License
016 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
017 */
018
019package org.jpos.space;
020
021import java.util.Set;
022
023/**
024 * Extension of {@link Space} with blocking read/take operations and space-listener support.
025 * @author Kris, Bharavi, Alejandro
026 * @version $Revision$ $Date$
027
028 * @param <K> the key type
029 * @param <V> the value type
030 */
031public interface LocalSpace<K,V> extends Space<K,V> {
032    /**
033     * add a SpaceListener associated with a given key
034     * @param key Entry's key
035     * @param listener a SpaceListener
036     */
037    void addListener(K key, SpaceListener<K, V> listener);
038
039    /**
040     * add a SpaceListener associated with a given key for a given 
041     * period of time.
042     * <b>Warning: not supported by all space implementations.</b>
043     * @param key Entry's key
044     * @param listener a SpaceListener
045     * @param timeout listener registration timeout in millis
046     */
047    void addListener(K key, SpaceListener<K, V> listener, long timeout);
048
049    /**
050     * removes a SpaceListener associated with a given key
051     * @param key Entry's key
052     * @param listener the SpaceListener
053     */
054    void removeListener(K key, SpaceListener<K, V> listener);
055
056    /**
057     * Returns the set of all keys currently present in the space.
058     * @return Set containing all keys in Space
059     */
060    Set<K> getKeySet();
061
062    /**
063     * Returns the number of entries queued under the given key.
064     * @param key the key to query
065     * @return number of entries in a given key
066     */
067    int size(K key);
068}