/* DTP.java --
   Copyright (C) 2003, 2004  Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
 
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WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
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package gnu.java.net.protocol.ftp;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/**
 * An FTP data transfer process.
 *
 * @author Chris Burdess (dog@gnu.org)
 */
interface DTP
{

  /**
   * Returns an input stream from which a remote file can be read.
   */
  InputStream getInputStream()
    throws IOException;

  /**
   * Returns an output stream to which a local file can be written for
   * upload.
   */
  OutputStream getOutputStream()
    throws IOException;

  /**
   * Sets the transfer mode to be used with this DTP.
   */
  void setTransferMode(int mode);

  /**
   * Marks this DTP completed.
   * When the current transfer has finished, any resources will be released.
   */
  void complete();

  /**
   * Aborts any current transfer and releases all resources held by this
   * DTP.
   * @return true if a transfer was interrupted, false otherwise
   */
  boolean abort();

  /**
   * Used to notify the DTP that its current transfer is complete.
   * This occurs either when end-of-stream is reached or a 226 response is
   * received.
   */
  void transferComplete();

}