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 * http://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 */ 017 018package org.apache.commons.net.io; 019 020import java.util.EventListener; 021 022/** 023 * The CopyStreamListener class can accept CopyStreamEvents to keep track of the progress of a stream copying operation. However, it is currently not used that 024 * way within NetComponents for performance reasons. Rather the bytesTransferred(long, int) method is called directly rather than passing an event to 025 * bytesTransferred(CopyStreamEvent), saving the creation of a CopyStreamEvent instance. Also, the only place where CopyStreamListener is currently used within 026 * NetComponents is in the static methods of the uninstantiable org.apache.commons.io.Util class, which would preclude the use of addCopyStreamListener and 027 * removeCopyStreamListener methods. However, future additions may use the JavaBean event model, which is why the hooks have been included from the beginning. 028 * 029 * 030 * @see CopyStreamEvent 031 * @see CopyStreamAdapter 032 * @see Util 033 */ 034public interface CopyStreamListener extends EventListener { 035 /** 036 * 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 037 * bytes transferred so far and the number of bytes transferred in the last write. 038 * 039 * @param event The CopyStreamEvent fired by the copying of a block of bytes. 040 */ 041 void bytesTransferred(CopyStreamEvent event); 042 043 /** 044 * 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 045 * after a block of bytes to inform the listener of the transfer. 046 * 047 * @param totalBytesTransferred The total number of bytes transferred so far by the copy operation. 048 * @param bytesTransferred The number of bytes copied by the most recent write. 049 * @param streamSize The number of bytes in the stream being copied. This may be equal to CopyStreamEvent.UNKNOWN_STREAM_SIZE if the size is 050 * unknown. 051 */ 052 void bytesTransferred(long totalBytesTransferred, int bytesTransferred, long streamSize); 053}