package org.eclipse.aether.transport.classpath;
   
   /*
    * 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.net.URI;
  import java.net.URISyntaxException;
  import java.net.URL;
  import java.net.URLConnection;
  
  import org.eclipse.aether.RepositorySystemSession;
  import org.eclipse.aether.repository.RemoteRepository;
  import org.eclipse.aether.spi.connector.transport.AbstractTransporter;
  import org.eclipse.aether.spi.connector.transport.GetTask;
  import org.eclipse.aether.spi.connector.transport.PeekTask;
  import org.eclipse.aether.spi.connector.transport.PutTask;
  import org.eclipse.aether.spi.connector.transport.TransportTask;
  import org.eclipse.aether.transfer.NoTransporterException;
  import org.eclipse.aether.util.ConfigUtils;
  
  /**
   * A transporter reading from the classpath.
   */
  final class ClasspathTransporter
      extends AbstractTransporter
  {
  
      private final String resourceBase;
  
      private final ClassLoader classLoader;
  
      ClasspathTransporter( RepositorySystemSession session, RemoteRepository repository )
          throws NoTransporterException
      {
          if ( !"classpath".equalsIgnoreCase( repository.getProtocol() ) )
          {
              throw new NoTransporterException( repository );
          }
  
          String base;
          try
          {
              URI uri = new URI( repository.getUrl() );
              String ssp = uri.getSchemeSpecificPart();
              if ( ssp.startsWith( "/" ) )
              {
                  base = uri.getPath();
                  if ( base == null )
                  {
                      base = "";
                  }
                  else if ( base.startsWith( "/" ) )
                  {
                      base = base.substring( 1 );
                  }
              }
              else
              {
                  base = ssp;
              }
              if ( base.length() > 0 && !base.endsWith( "/" ) )
              {
                  base += '/';
              }
          }
          catch ( URISyntaxException e )
          {
              throw new NoTransporterException( repository, e );
          }
          resourceBase = base;
  
          Object cl = ConfigUtils.getObject( session, null, ClasspathTransporterFactory.CONFIG_PROP_CLASS_LOADER );
          if ( cl instanceof ClassLoader )
          {
              classLoader = (ClassLoader) cl;
          }
          else
          {
              classLoader = Thread.currentThread().getContextClassLoader();
          }
      }
  
      private URL getResource( TransportTask task )
         throws Exception
     {
         String resource = resourceBase + task.getLocation().getPath();
         URL url = classLoader.getResource( resource );
         if ( url == null )
         {
             throw new ResourceNotFoundException( "Could not locate " + resource );
         }
         return url;
     }
 
     public int classify( Throwable error )
     {
         if ( error instanceof ResourceNotFoundException )
         {
             return ERROR_NOT_FOUND;
         }
         return ERROR_OTHER;
     }
 
     @Override
     protected void implPeek( PeekTask task )
         throws Exception
     {
         getResource( task );
     }
 
     @Override
     protected void implGet( GetTask task )
         throws Exception
     {
         URL url = getResource( task );
         URLConnection conn = url.openConnection();
         utilGet( task, conn.getInputStream(), true, conn.getContentLength(), false );
     }
 
     @Override
     protected void implPut( PutTask task )
         throws Exception
     {
         throw new UnsupportedOperationException( "Uploading to a classpath: repository is not supported" );
     }
 
     @Override
     protected void implClose()
     {
     }
 
 }