CTK/Libs/PluginFramework/ctkApplicationRunnable.h

/*=============================================================================

  Library: CTK

  Copyright (c) German Cancer Research Center,
    Division of Medical and Biological Informatics

  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.

=============================================================================*/

#ifndef CTKAPPLICATIONRUNNABLE_H
#define CTKAPPLICATIONRUNNABLE_H

#include <ctkPluginFrameworkExport.h>

class QVariant;

/**
 * Like a QRunnable, an object which captures a block of code which can
 * be passed around and executed as well as stopped.  Unlike standard runnables,
 * paramaterized runnables allow an arbitrary QVariant to be passed in when the
 * block is evaluated.
 * <p>
 * Clients may implement this interface.
 * </p>
 */
struct CTK_PLUGINFW_EXPORT ctkApplicationRunnable
{

  virtual ~ctkApplicationRunnable();

  /**
   * Executes the block of code encapsulated by this runnable in the context of
   * the given object and returns the result.  The result may be an invalid QVariant.
   *
   * @param context the context for evaluating the runnable
   * @return the result of evaluating the runnable in the given context
   * @throws std::exception if there is a problem running this runnable
   */
  virtual QVariant run(const QVariant& context) = 0;

  /**
   * Forces this runnable to stop.
   */
  virtual void stop() = 0;

};

#endif // CTKAPPLICATIONRUNNABLE_H