/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.commons.net.io; import java.util.EventListener; import org.apache.commons.net.util.ListenerList; /** * The CopyStreamAdapter will relay CopyStreamEvents to a list of listeners * when either of its bytesTransferred() methods are called. Its purpose * is to facilitate the notification of the progress of a copy operation * performed by one of the static copyStream() methods in * org.apache.commons.io.Util to multiple listeners. The static * copyStream() methods invoke the * bytesTransfered(long, int) of a CopyStreamListener for performance * reasons and also because multiple listeners cannot be registered given * that the methods are static. * <p> * <p> * @see CopyStreamEvent * @see CopyStreamListener * @see Util * @author <a href="mailto:savarese@apache.org">Daniel F. Savarese</a> * @version $Id: CopyStreamAdapter.java 489397 2006-12-21 16:28:51Z rwinston $ */ public class CopyStreamAdapter implements CopyStreamListener { private ListenerList internalListeners; /** * Creates a new copyStreamAdapter. */ public CopyStreamAdapter() { internalListeners = new ListenerList(); } /** * 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 bytes transferred so far and the number of bytes * transferred in the last write. The CopyStreamAdapater will relay * the event to all of its registered listeners, listing itself as the * source of the event. * @param event The CopyStreamEvent fired by the copying of a block of * bytes. */ public void bytesTransferred(CopyStreamEvent event) { bytesTransferred(event.getTotalBytesTransferred(), event.getBytesTransferred(), event.getStreamSize()); } /** * 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 after a block of bytes to inform the listener of the * transfer. The CopyStreamAdapater will create a CopyStreamEvent * from the arguments and relay the event to all of its registered * listeners, listing itself as the source of the event. * @param totalBytesTransferred The total number of bytes transferred * so far by the copy operation. * @param bytesTransferred The number of bytes copied by the most recent * write. * @param streamSize The number of bytes in the stream being copied. * This may be equal to CopyStreamEvent.UNKNOWN_STREAM_SIZE if * the size is unknown. */ public void bytesTransferred(long totalBytesTransferred, int bytesTransferred, long streamSize) { CopyStreamEvent event; event = new CopyStreamEvent(this, totalBytesTransferred, bytesTransferred, streamSize); for (EventListener listener : internalListeners) { ((CopyStreamListener) (listener)).bytesTransferred(event); } } /** * Registers a CopyStreamListener to receive CopyStreamEvents. * Although this method is not declared to be synchronized, it is * implemented in a thread safe manner. * @param listener The CopyStreamlistener to register. */ public void addCopyStreamListener(CopyStreamListener listener) { internalListeners.addListener(listener); } /** * Unregisters a CopyStreamListener. Although this method is not * synchronized, it is implemented in a thread safe manner. * @param listener The CopyStreamlistener to unregister. */ public void removeCopyStreamListener(CopyStreamListener listener) { internalListeners.removeListener(listener); } }