package org.apache.maven.plugins.checkstyle.resource;
   
   /*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.
   */
  
  import java.util.Map;
  
  import org.codehaus.plexus.component.annotations.Component;
  import org.codehaus.plexus.component.annotations.Requirement;
  import org.codehaus.plexus.resource.DefaultResourceManager;
  import org.codehaus.plexus.resource.PlexusResource;
  import org.codehaus.plexus.resource.ResourceManager;
  import org.codehaus.plexus.resource.loader.ResourceLoader;
  import org.codehaus.plexus.resource.loader.ResourceNotFoundException;
  import org.codehaus.plexus.resource.loader.ThreadContextClasspathResourceLoader;
  
  /**
   * License resource manager, to avoid defaulting license to maven-checkstyle-plugin's own license.
   *
   * @since 2.12
   */
  @Component( role = ResourceManager.class, hint = "license", instantiationStrategy = "per-lookup" )
  public class LicenseResourceManager
      extends DefaultResourceManager
  {
  
      @Requirement( role = ResourceLoader.class )
      private Map<String, ResourceLoader> resourceLoaders;
  
      @Override
      public void addSearchPath( String id, String path )
      {
          ResourceLoader loader = resourceLoaders.get( id );
  
          if ( loader == null )
          {
              throw new IllegalArgumentException( "unknown resource loader: " + id );
          }
  
          loader.addSearchPath( path );
      }
  
      @Override
      public PlexusResource getResource( String name )
          throws ResourceNotFoundException
      {
          for ( ResourceLoader resourceLoader : resourceLoaders.values() )
          {
              if ( resourceLoader instanceof ThreadContextClasspathResourceLoader
                  && !"config/maven-header.txt".equals( name ) )
              {
                  // MCHECKSTYLE-219: Don't load the license from the plugin
                  // classloader, only allow config/maven-header.txt
                  continue;
              }
  
              try
              {
                  PlexusResource resource = resourceLoader.getResource( name );
  
                  getLogger().debug( "The resource '" + name + "' was found as " + resource.getName() + "." );
  
                  return resource;
              }
              catch ( ResourceNotFoundException e )
              {
                  getLogger().debug( "The resource '" + name + "' was not found with resourceLoader "
                                         + resourceLoader.getClass().getName() + "." );
              }
          }
  
          throw new ResourceNotFoundException( name );
      }
  }