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