org.apache.xbean.kernel.StopStrategies Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of xbean-kernel Show documentation
The newest version!
/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information 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 with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.xbean.kernel;

import java.util.Set;

/**
 * This class contains the built-in common stop startegies.
 *
 * @author Dain Sundstrom
 * @version $Id$
 * @since 2.0
 */
public final class StopStrategies {
    private StopStrategies() {
    }

    /**
     * This strategy attempts to immedately stop the service.  When there are unsatisfied conditions, this strategy
     * will leave the service in the STOPPING state, and throw an UnsatisfiedConditionsException
     * to the caller.
     */
    public static final StopStrategy SYNCHRONOUS = new Synchronous();

    private static class Synchronous implements StopStrategy {
        public boolean waitForUnsatisfiedConditions(ServiceName serviceName, Set conditions) throws UnsatisfiedConditionsException {
            throw new UnsatisfiedConditionsException("Unsatisfied stop conditions", serviceName, conditions);
        }

    }

    /**
     * This strategy attempts to stop the service asynchronously.  When there are unsatisfied conditions, this strategy
     * will leave the service in the STOPPING state, and caller will not recieve any exceptions.
     */
    public static final StopStrategy ASYNCHRONOUS = new Asynchronous();

    private static class Asynchronous implements StopStrategy {
        public boolean waitForUnsatisfiedConditions(ServiceName serviceName, Set conditions) {
            return false;
        }

    }

    /**
     * This strategy wait until the service stops.  This strategy blocks until all unsatisfied conditons
     * are satisfied.
     */
    public static final StopStrategy BLOCK = new Block();

    private static class Block implements StopStrategy {
        public boolean waitForUnsatisfiedConditions(ServiceName serviceName, Set conditions) {
            return true;
        }

    }

    /**
     * This strategy forceable stops the service.  This strategy ignores all unsatisfied conditons.
     */
    public static final StopStrategy FORCE = new Force();

    private static class Force implements StopStrategy {
        public boolean waitForUnsatisfiedConditions(ServiceName serviceName, Set conditions) throws ForcedStopException {
            throw new ForcedStopException(serviceName, conditions);
        }

    }
}