Java tutorial
/* * 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.nifi.processor.util.put.sender; import org.apache.commons.io.IOUtils; import org.apache.nifi.logging.ComponentLog; import org.apache.nifi.remote.io.socket.SocketChannelOutputStream; import java.io.IOException; import java.net.InetAddress; import java.net.InetSocketAddress; import java.net.SocketTimeoutException; import java.net.StandardSocketOptions; import java.nio.channels.SocketChannel; /** * Sends messages over a SocketChannel. */ public class SocketChannelSender extends ChannelSender { protected SocketChannel channel; protected SocketChannelOutputStream socketChannelOutput; public SocketChannelSender(final String host, final int port, final int maxSendBufferSize, final ComponentLog logger) { super(host, port, maxSendBufferSize, logger); } @Override public void open() throws IOException { if (channel == null) { channel = SocketChannel.open(); channel.configureBlocking(false); if (maxSendBufferSize > 0) { channel.setOption(StandardSocketOptions.SO_SNDBUF, maxSendBufferSize); final int actualSendBufSize = channel.getOption(StandardSocketOptions.SO_SNDBUF); if (actualSendBufSize < maxSendBufferSize) { logger.warn("Attempted to set Socket Send Buffer Size to " + maxSendBufferSize + " bytes but could only set to " + actualSendBufSize + "bytes. You may want to " + "consider changing the Operating System's maximum receive buffer"); } } } if (!channel.isConnected()) { final long startTime = System.currentTimeMillis(); final InetSocketAddress socketAddress = new InetSocketAddress(InetAddress.getByName(host), port); if (!channel.connect(socketAddress)) { while (!channel.finishConnect()) { if (System.currentTimeMillis() > startTime + timeout) { throw new SocketTimeoutException("Timed out connecting to " + host + ":" + port); } try { Thread.sleep(50L); } catch (final InterruptedException e) { } } } socketChannelOutput = new SocketChannelOutputStream(channel); socketChannelOutput.setTimeout(timeout); } } @Override protected void write(byte[] data) throws IOException { socketChannelOutput.write(data); } @Override public boolean isConnected() { return channel != null && channel.isConnected(); } @Override public void close() { IOUtils.closeQuietly(socketChannelOutput); IOUtils.closeQuietly(channel); socketChannelOutput = null; channel = null; } }