package eu.fbk.knowledgestore.filestore;
   
   import java.io.IOException;
   import java.io.InputStream;
   import java.io.OutputStream;
   
   import com.google.common.collect.ForwardingObject;
   
   import eu.fbk.knowledgestore.data.Stream;
  
  /**
   * A {@code FileStore} that forwards all its method calls to another {@code FileStore}.
   * <p>
   * This class provides a starting point for implementing the decorator pattern on top of the
   * {@code FileStore} interface. Subclasses must implement method {@link #delegate()} and override
   * the methods of {@code FileStore} they want to decorate.
   * </p>
   */
  public abstract class ForwardingFileStore extends ForwardingObject implements FileStore {
  
  	@Override
  	protected abstract FileStore delegate();
  
  	@Override
  	public void init() throws IOException {
  		delegate().init();
  	}
  
  	@Override
  	public InputStream read(final String filename) throws FileMissingException, IOException {
  		return delegate().read(filename);
  	}
  
  	@Override
  	public OutputStream write(final String filename) throws FileExistsException, IOException {
  		return delegate().write(filename);
  	}
  
  	@Override
  	public void delete(final String filename) throws FileMissingException, IOException {
  		delegate().delete(filename);
  	}
  
  	@Override
  	public Stream<String> list() throws IOException {
  		return delegate().list();
  	}
  
  	@Override
  	public void close() {
  		delegate().close();
  	}
  
  }