ExternalPlugins.java

/*
 * Copyright 2016 Igor Maznitsa.
 *
 * 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 com.igormaznitsa.mindmap.plugins.external;

import java.io.File;
import java.util.Collection;
import java.util.Locale;
import javax.annotation.Nonnull;
import org.apache.commons.io.FileUtils;
import com.igormaznitsa.commons.version.Version;
import com.igormaznitsa.commons.version.VersionValidator;
import com.igormaznitsa.meta.common.utils.GetUtils;
import com.igormaznitsa.mindmap.model.logger.Logger;
import com.igormaznitsa.mindmap.model.logger.LoggerFactory;
import com.igormaznitsa.mindmap.plugins.MindMapPluginRegistry;
import com.igormaznitsa.mindmap.plugins.api.MindMapPlugin;

public class ExternalPlugins {
  
  private static final Logger LOGGER = LoggerFactory.getLogger(ExternalPlugins.class);
  
  private final File pluginsFolder;
  private static final String PLUGIN_EXTENSION = "mmdp";
  private final VersionValidator pluginApiValidator;
  
  public ExternalPlugins(@Nonnull final File pluginsFolder) {
    this.pluginApiValidator = new VersionValidator(">="+MindMapPlugin.API.toString());
    this.pluginsFolder = pluginsFolder;
    LOGGER.info("External plugins folder is "+pluginsFolder);
  }
  
  public void init() {
    final Collection<File> plugins = FileUtils.listFiles(this.pluginsFolder, new String[]{PLUGIN_EXTENSION,PLUGIN_EXTENSION.toUpperCase(Locale.ENGLISH)}, false);
    LOGGER.info("Detected "+plugins.size()+" plugin(s)");
    for(final File plugin : plugins){
      try{
        final PluginClassLoader loader = new PluginClassLoader(plugin);
        final String pluginTitle = GetUtils.ensureNonNull(loader.getAttributes(Attribute.TITLE),"<unknown>");
        final Version pluginVersion = new Version(loader.getAttributes(Attribute.VERSION));
        
        LOGGER.info(String.format("Detected plugin %s [%s]",pluginTitle,pluginVersion.toString()));
        final Version pluginApiVersion = loader.getApiVersion();
        if (this.pluginApiValidator.isValid(pluginApiVersion)){
          LOGGER.info(String.format("Plugin %s [%s] is valid for API", pluginTitle, pluginVersion.toString()));
          final String [] classes = loader.extractPluginClassNames();
          for(final String klazzName : classes){
            LOGGER.info(String.format("Loading plugin class %s from %s",klazzName,pluginTitle));
            final MindMapPlugin pluginInstance = (MindMapPlugin) loader.loadClass(klazzName).newInstance();
            MindMapPluginRegistry.getInstance().registerPlugin(pluginInstance);
          }
        } else {
          LOGGER.warn(String.format("Plugin %s [%s] is not valid for API : %s", pluginTitle, pluginVersion.toString(), pluginApiVersion.toString()));
        }
      }catch(Exception ex){
        LOGGER.error("Can't load plugin from : "+plugin.getAbsolutePath(), ex);
      }
    }
  }
}