View Javadoc

    1   /*
    2    * Copyright 2001-2005 The Apache Software Foundation
    3    *
    4    * Licensed under the Apache License, Version 2.0 (the "License");
    5    * you may not use this file except in compliance with the License.
    6    * You may obtain a copy of the License at
    7    *
    8    *     http://www.apache.org/licenses/LICENSE-2.0
    9    *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  package org.apache.commons.net.io;
    17
    18  import java.util.EventListener;
    19
    20  /***
    21   * The CopyStreamListener class can accept CopyStreamEvents to keep track
    22   * of the progress of a stream copying operation.  However, it is currently
    23   * not used that way within NetComponents for performance reasons.  Rather
    24   * the bytesTransferred(long, int) method is called directly rather than
    25   * passing an event to bytesTransferred(CopyStreamEvent), saving the creation
    26   * of a CopyStreamEvent instance.  Also, the only place where
    27   * CopyStreamListener is currently used within NetComponents is in the
    28   * static methods of the uninstantiable org.apache.commons.io.Util class, which
    29   * would preclude the use of addCopyStreamListener and
    30   * removeCopyStreamListener methods.  However, future additions may use the
    31   * JavaBean event model, which is why the hooks have been included from the
    32   * beginning.
    33   * <p>
    34   * <p>
    35   * @see CopyStreamEvent
    36   * @see CopyStreamAdapter
    37   * @see Util
    38   * @author <a href="mailto:savarese@apache.org">Daniel F. Savarese</a>
    39   * @version $Id: CopyStreamListener.java 165675 2005-05-02 20:09:55Z rwinston $
    40   */
    41  public interface CopyStreamListener extends EventListener
    42  {
    43      /***
    44       * This method is invoked by a CopyStreamEvent source after copying
    45       * a block of bytes from a stream.  The CopyStreamEvent will contain
    46       * the total number of bytes transferred so far and the number of bytes
    47       * transferred in the last write.
    48       * @param event The CopyStreamEvent fired by the copying of a block of
    49       *              bytes.
    50       */
    51      public void bytesTransferred(CopyStreamEvent event);
    52
    53
    54      /***
    55       * This method is not part of the JavaBeans model and is used by the
    56       * static methods in the org.apache.commons.io.Util class for efficiency.
    57       * It is invoked after a block of bytes to inform the listener of the
    58       * transfer.
    59       * @param totalBytesTransferred  The total number of bytes transferred
    60       *         so far by the copy operation.
    61       * @param bytesTransferred  The number of bytes copied by the most recent
    62       *          write.
    63       * @param streamSize The number of bytes in the stream being copied.
    64       *        This may be equal to CopyStreamEvent.UNKNOWN_STREAM_SIZE if
    65       *        the size is unknown.
    66       */
    67      public void bytesTransferred(long totalBytesTransferred,
    68                                   int bytesTransferred,
    69                                   long streamSize);
    70  }