pl.bristleback.server.bristle.actions.ActionsInitializer Maven / Gradle / Ivy

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// Bristleback plugin - Copyright (c) 2010 bristleback.googlecode.com
// ---------------------------------------------------------------------------
// This program is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License as published by the
// Free Software Foundation; either version 3 of the License, or (at your
// option) any later version.
// This library is distributed in the hope that it will be useful,
// but without any warranty; without even the implied warranty of merchantability
// or fitness for a particular purpose.
// You should have received a copy of the GNU Lesser General Public License along
// with this program; if not, see .
// ---------------------------------------------------------------------------
package pl.bristleback.server.bristle.actions;

import org.apache.commons.lang.StringUtils;
import org.apache.log4j.Logger;
import pl.bristleback.server.bristle.config.ActionAnnotationsProcessor;
import pl.bristleback.server.bristle.config.BristleConstants;
import pl.bristleback.server.bristle.config.PackageActionAnnotationsProcessor;
import pl.bristleback.server.bristle.exceptions.BristleRuntimeException;
import pl.bristleback.server.bristle.exceptions.ImplementationResolvingException;
import pl.bristleback.server.bristle.integration.spring.SpringIntegrationUtil;
import pl.bristleback.server.bristle.utils.ResolverUtil;

import java.util.List;
import java.util.Map;

/**
 * Helper class used to retrieve annotated actions, opaqued in {@link ActionsContainer} object and to inject Spring dependencies.
 * Firstly, creator instantiates annotation processor class.
 * Then processor object method is invoked and returns result of work of that processor.
 * Method {@link ActionsInitializer#injectActionsDependencies()} is invoked by plugin to inject dependencies.
 * 
 * Created on: 2010-10-04 17:15:29 

 *
 * @author Wojciech Niemiec
 */
public final class ActionsInitializer {
  private static Logger log = Logger.getLogger(ActionsInitializer.class.getName());

  public static final Class ACTION_ANNOTATION_DEFAULT_PROCESSOR_CLASS = PackageActionAnnotationsProcessor.class;

  private ActionsContainer container;

  /**
   * Gets previously created actions container. Returns null if container was not created yet.
   *
   * @return actions container.
   */
  public ActionsContainer getContainer() {
    return container;
  }

  /**
   * Loads actions using {@link ActionAnnotationsProcessor} implementation.
   * Implementation of action annotations processor can be specified by user by setting plugin property with name
   * {@link pl.bristleback.server.bristle.config.BristleConstants#ACTION_CLASS_RESOLVER_CLASS_PARAMETER_NAME}.
   *
   * @param pluginSettings plugin settings map
   */
  public void loadActionsContainer(Map pluginSettings) {
    initialize();
    String actionClassResolverName = pluginSettings.get(BristleConstants.ACTION_CLASS_RESOLVER_CLASS_PARAMETER_NAME);
    Class resolverClass = getResolverClass(actionClassResolverName);
    loadActionsByResolver(pluginSettings, resolverClass);
  }

  private void initialize() {
    if (container != null) {
      throw new BristleRuntimeException("actions already initialized");
    }
    container = new ActionsContainer();
  }

  private Class getResolverClass(String actionClassResolverName) {
    if (StringUtils.isEmpty(actionClassResolverName)) {
      if (log.isDebugEnabled()) {
        log.debug("Action class resolver is not specified by user, system will use default resolver");
      }
      return ACTION_ANNOTATION_DEFAULT_PROCESSOR_CLASS;
    } else {
      ResolverUtil resolver = new ResolverUtil();
      return resolver.getImplementation(ActionAnnotationsProcessor.class, actionClassResolverName);
    }
  }

  private void loadActionsByResolver(Map pluginSettings, Class actionClassResolver) {
    ActionAnnotationsProcessor actionAnnotationsProcessor;
    actionAnnotationsProcessor = getAnnotationProcessor(actionClassResolver);
    List actions = actionAnnotationsProcessor.getAnnotatedActions(pluginSettings);
    for (RemoteActionInformation action : actions) {
      addAction(action);
    }
  }

  private ActionAnnotationsProcessor getAnnotationProcessor(Class actionClassResolver) {
    ActionAnnotationsProcessor actionAnnotationsProcessor;
    try {
      actionAnnotationsProcessor = (ActionAnnotationsProcessor) (actionClassResolver.newInstance());
    } catch (Exception e) {
      throw new ImplementationResolvingException(actionClassResolver.getName(), ActionAnnotationsProcessor.class);
    }
    return actionAnnotationsProcessor;
  }

  private void addAction(RemoteActionInformation actionInformation) {
    if (container.getAction(actionInformation.getActionName()) != null) {
      throw new BristleRuntimeException("action class with name " + actionInformation.getActionName() + "is already registered.");
    }
    container.addAction(actionInformation);
  }

  /**
   * Inject Spring dependencies using {@link pl.bristleback.server.bristle.integration.spring.SpringIntegrationUtil} class.
   */
  public void injectActionsDependencies() {
    for (RemoteActionInformation actionInformation : container.getAllActions()) {
      SpringIntegrationUtil.injectAnnotatedBeans(actionInformation.getAction());
    }
  }
}