| /** |
| * 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.IOException; |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import java.io.InputStream; |
| import java.net.Socket; |
| import java.net.SocketTimeoutException; |
| import java.nio.ByteBuffer; |
| import java.nio.channels.FileChannel; |
| import java.nio.channels.ReadableByteChannel; |
| import java.nio.channels.SelectableChannel; |
| import java.nio.channels.SelectionKey; |
| |
| /** |
| * This implements an input stream that can have a timeout while reading. |
| * This sets non-blocking flag on the socket channel. |
| * So after create this object, read() on |
| * {@link Socket#getInputStream()} and write() on |
| * {@link Socket#getOutputStream()} for the associated socket will throw |
| * IllegalBlockingModeException. |
| * Please use {@link SocketOutputStream} for writing. |
| */ |
| @InterfaceAudience.LimitedPrivate("HDFS") |
| public class SocketInputStream extends InputStream |
| implements ReadableByteChannel { |
| |
| private Reader reader; |
| |
| private static class Reader extends SocketIOWithTimeout { |
| ReadableByteChannel channel; |
| |
| Reader(ReadableByteChannel channel, long timeout) throws IOException { |
| super((SelectableChannel)channel, timeout); |
| this.channel = channel; |
| } |
| |
| @Override |
| int performIO(ByteBuffer buf) throws IOException { |
| return channel.read(buf); |
| } |
| } |
| |
| /** |
| * Create a new input stream with the given timeout. If the timeout |
| * is zero, it will be treated as infinite timeout. The socket's |
| * channel will be configured to be non-blocking. |
| * |
| * @param channel |
| * Channel for reading, should also be a {@link SelectableChannel}. |
| * The channel will be configured to be non-blocking. |
| * @param timeout timeout in milliseconds. must not be negative. |
| * @throws IOException |
| */ |
| public SocketInputStream(ReadableByteChannel channel, long timeout) |
| throws IOException { |
| SocketIOWithTimeout.checkChannelValidity(channel); |
| reader = new Reader(channel, timeout); |
| } |
| |
| /** |
| * Same as SocketInputStream(socket.getChannel(), timeout): <br><br> |
| * |
| * Create a new input stream with the given timeout. If the timeout |
| * is zero, it will be treated as infinite timeout. The socket's |
| * channel will be configured to be non-blocking. |
| * |
| * @see SocketInputStream#SocketInputStream(ReadableByteChannel, long) |
| * |
| * @param socket should have a channel associated with it. |
| * @param timeout timeout timeout in milliseconds. must not be negative. |
| * @throws IOException |
| */ |
| public SocketInputStream(Socket socket, long timeout) |
| throws IOException { |
| this(socket.getChannel(), timeout); |
| } |
| |
| /** |
| * Same as SocketInputStream(socket.getChannel(), socket.getSoTimeout()) |
| * :<br><br> |
| * |
| * Create a new input stream with the given timeout. If the timeout |
| * is zero, it will be treated as infinite timeout. The socket's |
| * channel will be configured to be non-blocking. |
| * @see SocketInputStream#SocketInputStream(ReadableByteChannel, long) |
| * |
| * @param socket should have a channel associated with it. |
| * @throws IOException |
| */ |
| public SocketInputStream(Socket socket) throws IOException { |
| this(socket.getChannel(), socket.getSoTimeout()); |
| } |
| |
| @Override |
| public int read() throws IOException { |
| /* Allocation can be removed if required. |
| * probably no need to optimize or encourage single byte read. |
| */ |
| byte[] buf = new byte[1]; |
| int ret = read(buf, 0, 1); |
| if (ret > 0) { |
| return (int)(buf[0] & 0xff); |
| } |
| if (ret != -1) { |
| // unexpected |
| throw new IOException("Could not read from stream"); |
| } |
| return ret; |
| } |
| |
| @Override |
| public int read(byte[] b, int off, int len) throws IOException { |
| return read(ByteBuffer.wrap(b, off, len)); |
| } |
| |
| @Override |
| public synchronized void close() throws IOException { |
| /* close the channel since Socket.getInputStream().close() |
| * closes the socket. |
| */ |
| reader.channel.close(); |
| reader.close(); |
| } |
| |
| /** |
| * Returns underlying channel used by inputstream. |
| * This is useful in certain cases like channel for |
| * {@link FileChannel#transferFrom(ReadableByteChannel, long, long)}. |
| */ |
| public ReadableByteChannel getChannel() { |
| return reader.channel; |
| } |
| |
| //ReadableByteChannel interface |
| |
| @Override |
| public boolean isOpen() { |
| return reader.isOpen(); |
| } |
| |
| @Override |
| public int read(ByteBuffer dst) throws IOException { |
| return reader.doIO(dst, SelectionKey.OP_READ); |
| } |
| |
| /** |
| * waits for the underlying channel to be ready for reading. |
| * The timeout specified for this stream applies to this wait. |
| * |
| * @throws SocketTimeoutException |
| * if select on the channel times out. |
| * @throws IOException |
| * if any other I/O error occurs. |
| */ |
| public void waitForReadable() throws IOException { |
| reader.waitForIO(SelectionKey.OP_READ); |
| } |
| |
| public void setTimeout(long timeoutMs) { |
| reader.setTimeout(timeoutMs); |
| } |
| } |