CopyStreamAdapter.java
- /*
- * 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.
- *
- *
- * @see CopyStreamEvent
- * @see CopyStreamListener
- * @see Util
- */
- public class CopyStreamAdapter implements CopyStreamListener {
- private final ListenerList internalListeners;
- /**
- * Creates a new copyStreamAdapter.
- */
- public CopyStreamAdapter() {
- internalListeners = new ListenerList();
- }
- /**
- * 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(final CopyStreamListener listener) {
- internalListeners.addListener(listener);
- }
- /**
- * 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.
- */
- @Override
- public void bytesTransferred(final CopyStreamEvent event) {
- for (final EventListener listener : internalListeners) {
- ((CopyStreamListener) listener).bytesTransferred(event);
- }
- }
- /**
- * 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.
- */
- @Override
- public void bytesTransferred(final long totalBytesTransferred, final int bytesTransferred, final long streamSize) {
- for (final EventListener listener : internalListeners) {
- ((CopyStreamListener) listener).bytesTransferred(totalBytesTransferred, bytesTransferred, streamSize);
- }
- }
- /**
- * 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(final CopyStreamListener listener) {
- internalListeners.removeListener(listener);
- }
- }