.. _program_listing_file_include_class_loader_multi_library_class_loader.hpp:

Program Listing for File multi_library_class_loader.hpp
=======================================================

|exhale_lsh| :ref:`Return to documentation for file <file_include_class_loader_multi_library_class_loader.hpp>` (``include/class_loader/multi_library_class_loader.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   /*
    * Software License Agreement (BSD License)
    *
    * Copyright (c) 2012, Willow Garage, Inc.
    * All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions are met:
    *
    *     * Redistributions of source code must retain the above copyright
    *       notice, this list of conditions and the following disclaimer.
    *     * Redistributions in binary form must reproduce the above copyright
    *       notice, this list of conditions and the following disclaimer in the
    *       documentation and/or other materials provided with the distribution.
    *     * Neither the name of the copyright holders nor the names of its
    *       contributors may be used to endorse or promote products derived from
    *       this software without specific prior written permission.
    *
    * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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    * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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    */
   
   #ifndef CLASS_LOADER__MULTI_LIBRARY_CLASS_LOADER_HPP_
   #define CLASS_LOADER__MULTI_LIBRARY_CLASS_LOADER_HPP_
   
   #include <cstddef>
   #include <map>
   #include <memory>
   #include <string>
   #include <vector>
   
   // TODO(mikaelarguedas) remove this once console_bridge complies with this
   // see https://github.com/ros/console_bridge/issues/55
   #ifdef __clang__
   # pragma clang diagnostic push
   # pragma clang diagnostic ignored "-Wgnu-zero-variadic-macro-arguments"
   #endif
   #include "console_bridge/console.h"
   #ifdef __clang__
   # pragma clang diagnostic pop
   #endif
   
   #include "class_loader/class_loader.hpp"
   #include "class_loader/visibility_control.hpp"
   
   namespace class_loader
   {
   
   typedef std::string LibraryPath;
   typedef std::map<LibraryPath, class_loader::ClassLoader *> LibraryToClassLoaderMap;
   typedef std::vector<ClassLoader *> ClassLoaderVector;
   
   class MultiLibraryClassLoaderImpl;
   
   class CLASS_LOADER_PUBLIC MultiLibraryClassLoader
   {
   public:
     explicit MultiLibraryClassLoader(bool enable_ondemand_loadunload);
   
     virtual ~MultiLibraryClassLoader();
   
     template<class Base>
     std::shared_ptr<Base> createInstance(const std::string & class_name)
     {
       CONSOLE_BRIDGE_logDebug(
         "class_loader::MultiLibraryClassLoader: "
         "Attempting to create instance of class type %s.",
         class_name.c_str());
       ClassLoader * loader = getClassLoaderForClass<Base>(class_name);
       if (nullptr == loader) {
         throw class_loader::CreateClassException(
                 "MultiLibraryClassLoader: Could not create object of class type " +
                 class_name +
                 " as no factory exists for it. Make sure that the library exists and " +
                 "was explicitly loaded through MultiLibraryClassLoader::loadLibrary()");
       }
   
       return loader->createInstance<Base>(class_name);
     }
   
     template<class Base>
     std::shared_ptr<Base> createInstance(
       const std::string & class_name, const std::string & library_path)
     {
       ClassLoader * loader = getClassLoaderForLibrary(library_path);
       if (nullptr == loader) {
         throw class_loader::NoClassLoaderExistsException(
                 "Could not create instance as there is no ClassLoader in "
                 "MultiLibraryClassLoader bound to library " + library_path +
                 " Ensure you called MultiLibraryClassLoader::loadLibrary()");
       }
       return loader->createInstance<Base>(class_name);
     }
   
   
     template<class Base>
     ClassLoader::UniquePtr<Base> createUniqueInstance(const std::string & class_name)
     {
       CONSOLE_BRIDGE_logDebug(
         "class_loader::MultiLibraryClassLoader: Attempting to create instance of class type %s.",
         class_name.c_str());
       ClassLoader * loader = getClassLoaderForClass<Base>(class_name);
       if (nullptr == loader) {
         throw class_loader::CreateClassException(
                 "MultiLibraryClassLoader: Could not create object of class type " + class_name +
                 " as no factory exists for it. "
                 "Make sure that the library exists and was explicitly loaded through "
                 "MultiLibraryClassLoader::loadLibrary()");
       }
       return loader->createUniqueInstance<Base>(class_name);
     }
   
   
     template<class Base>
     ClassLoader::UniquePtr<Base>
     createUniqueInstance(const std::string & class_name, const std::string & library_path)
     {
       ClassLoader * loader = getClassLoaderForLibrary(library_path);
       if (nullptr == loader) {
         throw class_loader::NoClassLoaderExistsException(
                 "Could not create instance as there is no ClassLoader in "
                 "MultiLibraryClassLoader bound to library " + library_path +
                 " Ensure you called MultiLibraryClassLoader::loadLibrary()");
       }
       return loader->createUniqueInstance<Base>(class_name);
     }
   
     template<class Base>
     Base * createUnmanagedInstance(const std::string & class_name)
     {
       ClassLoader * loader = getClassLoaderForClass<Base>(class_name);
       if (nullptr == loader) {
         throw class_loader::CreateClassException(
                 "MultiLibraryClassLoader: Could not create class of type " + class_name);
       }
       return loader->createUnmanagedInstance<Base>(class_name);
     }
   
     template<class Base>
     Base * createUnmanagedInstance(const std::string & class_name, const std::string & library_path)
     {
       ClassLoader * loader = getClassLoaderForLibrary(library_path);
       if (nullptr == loader) {
         throw class_loader::NoClassLoaderExistsException(
                 "Could not create instance as there is no ClassLoader in MultiLibraryClassLoader "
                 "bound to library " + library_path +
                 " Ensure you called MultiLibraryClassLoader::loadLibrary()");
       }
       return loader->createUnmanagedInstance<Base>(class_name);
     }
   
     template<class Base>
     bool isClassAvailable(const std::string & class_name) const
     {
       std::vector<std::string> available_classes = getAvailableClasses<Base>();
       return available_classes.end() != std::find(
         available_classes.begin(), available_classes.end(), class_name);
     }
   
     bool isLibraryAvailable(const std::string & library_path) const;
   
     template<class Base>
     std::vector<std::string> getAvailableClasses() const
     {
       std::vector<std::string> available_classes;
       for (auto & loader : getAllAvailableClassLoaders()) {
         std::vector<std::string> loader_classes = loader->getAvailableClasses<Base>();
         available_classes.insert(
           available_classes.end(), loader_classes.begin(), loader_classes.end());
       }
       return available_classes;
     }
   
     template<class Base>
     std::vector<std::string> getAvailableClassesForLibrary(const std::string & library_path)
     {
       ClassLoader * loader = getClassLoaderForLibrary(library_path);
       if (nullptr == loader) {
         throw class_loader::NoClassLoaderExistsException(
                 "There is no ClassLoader in MultiLibraryClassLoader bound to library " +
                 library_path +
                 " Ensure you called MultiLibraryClassLoader::loadLibrary()");
       }
       return loader->getAvailableClasses<Base>();
     }
   
     std::vector<std::string> getRegisteredLibraries() const;
   
     void loadLibrary(const std::string & library_path);
   
     int unloadLibrary(const std::string & library_path);
   
   private:
     bool isOnDemandLoadUnloadEnabled() const;
   
     ClassLoader * getClassLoaderForLibrary(const std::string & library_path);
   
   
     template<typename Base>
     ClassLoader * getClassLoaderForClass(const std::string & class_name)
     {
       ClassLoaderVector loaders = getAllAvailableClassLoaders();
       for (ClassLoaderVector::iterator i = loaders.begin(); i != loaders.end(); ++i) {
         if (!(*i)->isLibraryLoaded()) {
           (*i)->loadLibrary();
         }
         if ((*i)->isClassAvailable<Base>(class_name)) {
           return *i;
         }
       }
       return nullptr;
     }
   
     ClassLoaderVector getAllAvailableClassLoaders() const;
   
     void shutdownAllClassLoaders();
   
     MultiLibraryClassLoaderImpl * impl_;
   };
   
   
   }  // namespace class_loader
   #endif  // CLASS_LOADER__MULTI_LIBRARY_CLASS_LOADER_HPP_