001    /*
002     * ============================================================================
003     * GNU Lesser General Public License
004     * ============================================================================
005     *
006     * Beanlet - JSE Application Container.
007     * Copyright (C) 2006  Leon van Zantvoort
008     * 
009     * This library is free software; you can redistribute it and/or
010     * modify it under the terms of the GNU Lesser General Public
011     * License as published by the Free Software Foundation; either
012     * version 2.1 of the License, or (at your option) any later version.
013     * 
014     * This library is distributed in the hope that it will be useful,
015     * but WITHOUT ANY WARRANTY; without even the implied warranty of
016     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
017     * Lesser General Public License for more details.
018     * 
019     * You should have received a copy of the GNU Lesser General Public
020     * License along with this library; if not, write to the Free Software
021     * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
022     * 
023     * Leon van Zantvoort
024     * 243 Acalanes Drive #11
025     * Sunnyvale, CA 94086
026     * USA
027     *
028     * zantvoort@users.sourceforge.net
029     * http://beanlet.org
030     */
031    package org.beanlet;
032    
033    import java.lang.annotation.ElementType;
034    import java.lang.annotation.Retention;
035    import java.lang.annotation.RetentionPolicy;
036    import java.lang.annotation.Target;
037    
038    /**
039     * <p>Stateful beanlet maintain conversational state between calls on the same
040     * object. Stateful beanlets do not provide direct access to the underlying 
041     * objects. Instead, clients obtain a stub that delegates invocations to the 
042     * underlying instance. In case of stateful beanlets, the stub always delegates 
043     * invocation to the same instance.<br>
044     * A new beanlet instance is created for each beanlet that is explicitely 
045     * requested throuh the APIs, or implicitely through dependency injection.<br>
046     * Stateful beanlets are non {@code reentrant} by default, which means that only 
047     * one thread can invoke a method of the beanlet instance at the same time. 
048     * This feature is provided by the stub, which controls all access to the 
049     * underlying instance. Stateful beanlets can also be configured to be reentrant.</p>
050     *
051     * {@beanlet.annotation}
052     *
053     * @see Stateless
054     * @see ScopeAnnotation
055     * @author Leon van Zantvoort
056     */
057    @ScopeAnnotation
058    @Retention(RetentionPolicy.RUNTIME)
059    @Target(ElementType.TYPE)
060    public @interface Stateful {
061    
062        /**
063         * Specifies whether the beanlet instances should be reentrant or not. 
064         * Instances of reentrant beanlets can be invoked by multiple threads at
065         * the same time.
066         */
067        boolean reentrant() default false;
068    }