pf4j/pf4j/src/main/java/ro/fortsoft/pf4j/Plugin.java

/*
 * Copyright 2012 Decebal Suiu
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with
 * the License. You may obtain a copy of the License in the LICENSE file, or 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 ro.fortsoft.pf4j;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * This class will be extended by all plugins and
 * serve as the common class between a plugin and the application.
 *
 * @author Decebal Suiu
 */
public abstract class Plugin {

    /**
     * Makes logging service available for descending classes.
     */
    protected final Logger log = LoggerFactory.getLogger(getClass());

    /**
     * Wrapper of the plugin.
     */
    protected PluginWrapper wrapper;

    /**
     * Constructor to be used by plugin manager for plugin instantiation.
     * Your plugins have to provide constructor with this exact signature to
     * be successfully loaded by manager.
     */
    public Plugin(final PluginWrapper wrapper) {
        if (wrapper == null) {
            throw new IllegalArgumentException("Wrapper cannot be null");
        }

        this.wrapper = wrapper;
    }

    /**
     * Retrieves the wrapper of this plug-in.
     */
    public final PluginWrapper getWrapper() {
        return wrapper;
    }

    /**
     * Start method is called by the application when the plugin is loaded.
     */
    public void start() throws PluginException {
    }

    /**
     * Stop method is called by the application when the plugin is unloaded.
     */
    public void stop() throws PluginException {
    }

}