| /** |
| * 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.hadoop.net; |
| |
| import java.io.FilterInputStream; |
| |
| import java.io.InputStream; |
| import java.net.Socket; |
| import java.net.SocketException; |
| import java.nio.channels.ReadableByteChannel; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| |
| import com.google.common.base.Preconditions; |
| |
| /** |
| * A wrapper stream around a socket which allows setting of its timeout. If the |
| * socket has a channel, this uses non-blocking IO via the package-private |
| * {@link SocketInputStream} implementation. Otherwise, timeouts are managed by |
| * setting the underlying socket timeout itself. |
| */ |
| @InterfaceAudience.LimitedPrivate("HDFS") |
| @InterfaceStability.Unstable |
| public class SocketInputWrapper extends FilterInputStream { |
| private final Socket socket; |
| private final boolean hasChannel; |
| |
| SocketInputWrapper(Socket s, InputStream is) { |
| super(is); |
| this.socket = s; |
| this.hasChannel = s.getChannel() != null; |
| if (hasChannel) { |
| Preconditions.checkArgument(is instanceof SocketInputStream, |
| "Expected a SocketInputStream when there is a channel. " + |
| "Got: %s", is); |
| } |
| } |
| |
| /** |
| * Set the timeout for reads from this stream. |
| * |
| * Note: the behavior here can differ subtly depending on whether the |
| * underlying socket has an associated Channel. In particular, if there is no |
| * channel, then this call will affect the socket timeout for <em>all</em> |
| * readers of this socket. If there is a channel, then this call will affect |
| * the timeout only for <em>this</em> stream. As such, it is recommended to |
| * only create one {@link SocketInputWrapper} instance per socket. |
| * |
| * @param timeoutMs |
| * the new timeout, 0 for no timeout |
| * @throws SocketException |
| * if the timeout cannot be set |
| */ |
| public void setTimeout(long timeoutMs) throws SocketException { |
| if (hasChannel) { |
| ((SocketInputStream)in).setTimeout(timeoutMs); |
| } else { |
| socket.setSoTimeout((int)timeoutMs); |
| } |
| } |
| |
| /** |
| * @return an underlying ReadableByteChannel implementation. |
| * @throws IllegalStateException if this socket does not have a channel |
| */ |
| public ReadableByteChannel getReadableByteChannel() { |
| Preconditions.checkState(hasChannel, |
| "Socket %s does not have a channel", |
| this.socket); |
| return (SocketInputStream)in; |
| } |
| } |