001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * https://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.commons.net.io; 018 019import java.util.EventListener; 020 021/** 022 * Accepts {@link CopyStreamEvent}s to track the progress of a stream copying operation. However, it is currently not used that way within Net for performance 023 * reasons. Rather, the bytesTransferred(long, int) method is called directly rather than passing an event to bytesTransferred(CopyStreamEvent), saving the 024 * creation of a CopyStreamEvent instance. Also, the only place where CopyStreamListener is currently used within Net is in the static methods of the 025 * uninstantiable org.apache.commons.io.Util class, which would preclude the use of addCopyStreamListener and removeCopyStreamListener methods. However, future 026 * additions may use the JavaBean event model, which is why the hooks have been included from the beginning. 027 * 028 * @see CopyStreamEvent 029 * @see CopyStreamAdapter 030 * @see Util 031 */ 032public interface CopyStreamListener extends EventListener { 033 /** 034 * Accepts a source event after copying a block of bytes from a stream. The CopyStreamEvent will contain the total number of bytes transferred so far and 035 * the number of bytes transferred in the last write. 036 * 037 * @param event The CopyStreamEvent fired by the copying of a block of bytes. 038 */ 039 void bytesTransferred(CopyStreamEvent event); 040 041 /** 042 * 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 043 * after a block of bytes to inform the listener of the transfer. 044 * 045 * @param totalBytesTransferred The total number of bytes transferred so far by the copy operation. 046 * @param bytesTransferred The number of bytes copied by the most recent write. 047 * @param streamSize The number of bytes in the stream being copied. This may be equal to CopyStreamEvent.UNKNOWN_STREAM_SIZE if the size is 048 * unknown. 049 */ 050 void bytesTransferred(long totalBytesTransferred, int bytesTransferred, long streamSize); 051}