iofiltertransition.java

mina是以Java实现的一个开源的网络程序框架

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 *  Licensed to the Apache Software Foundation (ASF) under one
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 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
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 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
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 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
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package org.apache.mina.statemachine.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

import org.apache.mina.core.filterchain.IoFilter;
import org.apache.mina.statemachine.StateMachine;
import org.apache.mina.statemachine.event.IoFilterEvents;

/**
 * Annotation used on methods to indicate that the method handles a specific
 * kind of {@link IoFilterEvents} event when in a specific state. This should
 * be used when creating {@link StateMachine}s for MINA's {@link IoFilter}
 * interface.
 *
 * @author The Apache MINA Project ([e-mail])
 * @version $Rev: 671827 $, $Date: 2008-06-26 10:49:48 +0200 (Thu, 26 Jun 2008) $
 */
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
@TransitionAnnotation(IoFilterTransitions.class)
public @interface IoFilterTransition {
    /**
     * Specifies the ids of one or more events handled by the annotated method. If
     * not specified the handler method will be executed for any event.
     */
    IoFilterEvents[] on() default IoFilterEvents.ANY;

    /**
     * The id of the state or states that this handler applies to. Must be
     * specified.
     */
    String[] in();

    /**
     * The id of the state the {@link StateMachine} should move to next after
     * executing the annotated method. If not specified the {@link StateMachine}
     * will remain in the same state.
     */
    String next() default Transition.SELF;

    /**
     * The weight used to order handler annotations which match the same event 
     * in the same state. Transitions with lower weight will be matched first. The
     * default weight is 0.
     */
    int weight() default 0;
}