001    /**
002     *
003     * Copyright 2003-2004 The Apache Software Foundation
004     *
005     *  Licensed under the Apache License, Version 2.0 (the "License");
006     *  you may not use this file except in compliance with the License.
007     *  You may obtain a copy of the License at
008     *
009     *     http://www.apache.org/licenses/LICENSE-2.0
010     *
011     *  Unless required by applicable law or agreed to in writing, software
012     *  distributed under the License is distributed on an "AS IS" BASIS,
013     *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     *  See the License for the specific language governing permissions and
015     *  limitations under the License.
016     */
017    
018    package org.apache.geronimo.kernel.management;
019    
020    
021    /**
022     * A Java interface the meets the J2EE Management specification for a state manageable object.
023     *
024     * @version $Rev: 355877 $ $Date: 2005-12-10 18:48:27 -0800 (Sat, 10 Dec 2005) $
025     */
026    public interface StateManageable {
027        /**
028         * Gets the state of this component as an int.
029         * The int return is required by the JSR77 specification.
030         *
031         * @return the current state of this component
032         * @see #getStateInstance to obtain the State instance
033         */
034        int getState();
035    
036        /**
037         * Gets the state of this component as a State instance.
038         *
039         * @return the current state of this component
040         */
041        State getStateInstance();
042    
043        /**
044         * Gets the start time of this component
045         *
046         * @return time in milliseonds since epoch that this component was started.
047         */
048        long getStartTime();
049    
050    
051        /**
052         * Transitions the component to the starting state.  This method has access to the
053         * container.
054         * <p/>
055         * Normally a component uses this to cache data from other components. The other components will
056         * have been created at this stage, but not necessairly started and may not be ready to have methods
057         * invoked on them.
058         *
059         * @throws Exception if a problem occurs during the transition
060         * @throws IllegalStateException if this interceptor is not in the stopped or failed state
061         */
062        void start() throws Exception, IllegalStateException;
063    
064        /**
065         * Transitions the component to the starting state.  This method has access to the
066         * container.
067         * <p/>
068         * If this Component is a Container, then startRecursive is called on all child Components
069         * that are in the STOPPED or FAILED state.
070         * Normally a component uses this to cache data from other components. The other components will
071         * have been created at this stage, but not necessairly started and may not be ready to have methods
072         * invoked on them.
073         *
074         * @throws Exception if a problem occurs during the transition
075         * @throws IllegalStateException if this interceptor is not in the STOPPED or FAILED state
076         */
077        void startRecursive() throws Exception, IllegalStateException;
078    
079        /**
080         * Transitions the component to the stopping state.  This method has access to the
081         * container.
082         * <p/>
083         * If this is Component is a Container, then all its child components must be in the
084         * STOPPED or FAILED State.
085         * <p/>
086         * Normally a component uses this to drop references to data cached in the start method.
087         * The other components will not necessairly have been stopped at this stage and may not be ready
088         * to have methods invoked on them.
089         *
090         * @throws Exception if a problem occurs during the transition
091         * @throws IllegalStateException if this interceptor is not in the STOPPED or FAILED state
092         */
093        void stop() throws Exception, IllegalStateException;
094    
095    }