InternalBundleDelegationProvider.java

/**
 * Copyright OPS4J
 *
 * Licensed 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.ops4j.pax.wicket.internal;

import org.ops4j.pax.wicket.internal.extender.ExtendedBundle;

/**
 * This is quite a simple interface marking all BundleDelegating loaders used by the BundleDelegatingExtensionTracker
 * helping to provide an internal standard of methods for such classes.
 *
 * An additional important remark: Non of those classes implementing this interface have to handle synchronized
 * themselves, but have to be rather synchronized by the caller!
 *
 * @author nmw
 * @version $Id: $Id
 */
public interface InternalBundleDelegationProvider {

    /**
     * Each {@link org.ops4j.pax.wicket.internal.InternalBundleDelegationProvider} has to know the applicationName it is registered for. This method
     * returns the application name.
     *
     * @return a {@link java.lang.String} object.
     */
    String getApplicationName();

    /**
     * In this method the component has to start itself. It can either register a service or do any other operations.
     * Please keep in mind that {@link #addBundle(ExtendedBundle)} and {@link #removeBundle(ExtendedBundle)} couldn't be
     * called before this method is called and are likely to throw an {@link java.lang.IllegalStateException} otherwise.
     */
    void start();

    /**
     * In this method the component has to stop itself. It can unregister services or do any other operations for tear
     * down. Please keep in mind that neither the {@link #addBundle(ExtendedBundle)} nor the
     * {@link #removeBundle(ExtendedBundle)} are likely to work after this method is called and will throw an
     * {@link java.lang.IllegalStateException}.
     */
    void stop();

    /**
     * Adds a bundle which should be used for delegation. This will thrown an {@link java.lang.IllegalStateException} in case the
     * {@link #start()} method had not been called.
     *
     * @param bundle a {@link org.ops4j.pax.wicket.internal.extender.ExtendedBundle} object.
     */
    void addBundle(ExtendedBundle bundle);

    /**
     * Removes a bundle which shouldn't be used any longer for delegation. This will throw an
     * {@link java.lang.IllegalStateException} in case the {@link #start()} method had not been called already. If you try to
     * remove a bundle not added by now nothing happens.
     *
     * @param bundle a {@link org.ops4j.pax.wicket.internal.extender.ExtendedBundle} object.
     */
    void removeBundle(ExtendedBundle bundle);

}