org.apache.zookeeper.client.FourLetterWordMain Maven / Gradle / Ivy
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/*
* 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.zookeeper.client;
import static java.nio.charset.StandardCharsets.UTF_8;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketTimeoutException;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSocket;
import javax.net.ssl.SSLSocketFactory;
import org.apache.yetus.audience.InterfaceAudience;
import org.apache.zookeeper.common.ClientX509Util;
import org.apache.zookeeper.common.X509Exception.SSLContextException;
import org.apache.zookeeper.common.X509Util;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@InterfaceAudience.Public
public class FourLetterWordMain {
//in milliseconds, socket should connect/read within this period otherwise SocketTimeoutException
private static final int DEFAULT_SOCKET_TIMEOUT = 5000;
protected static final Logger LOG = LoggerFactory.getLogger(FourLetterWordMain.class);
/**
* Send the 4letterword
* @param host the destination host
* @param port the destination port
* @param cmd the 4letterword
* @return server response
* @throws java.io.IOException
* @throws SSLContextException
*/
public static String send4LetterWord(String host, int port, String cmd) throws IOException, SSLContextException {
return send4LetterWord(host, port, cmd, false, DEFAULT_SOCKET_TIMEOUT);
}
/**
* Send the 4letterword
* @param host the destination host
* @param port the destination port
* @param cmd the 4letterword
* @param secure whether to use SSL
* @return server response
* @throws java.io.IOException
* @throws SSLContextException
*/
public static String send4LetterWord(
String host,
int port,
String cmd,
boolean secure) throws IOException, SSLContextException {
return send4LetterWord(host, port, cmd, secure, DEFAULT_SOCKET_TIMEOUT);
}
/**
* Send the 4letterword
* @param host the destination host
* @param port the destination port
* @param cmd the 4letterword
* @param secure whether to use SSL
* @param timeout in milliseconds, maximum time to wait while connecting/reading data
* @return server response
* @throws java.io.IOException
* @throws SSLContextException
*/
public static String send4LetterWord(
String host,
int port,
String cmd,
boolean secure,
int timeout) throws IOException, SSLContextException {
LOG.info("connecting to {} {}", host, port);
Socket sock = null;
BufferedReader reader = null;
try {
InetSocketAddress hostaddress = host != null
? new InetSocketAddress(host, port)
: new InetSocketAddress(InetAddress.getByName(null), port);
if (secure) {
LOG.info("using secure socket");
try (X509Util x509Util = new ClientX509Util()) {
SSLContext sslContext = x509Util.getDefaultSSLContext();
SSLSocketFactory socketFactory = sslContext.getSocketFactory();
SSLSocket sslSock = (SSLSocket) socketFactory.createSocket();
sslSock.connect(hostaddress, timeout);
sslSock.startHandshake();
sock = sslSock;
}
} else {
sock = new Socket();
sock.connect(hostaddress, timeout);
}
sock.setSoTimeout(timeout);
OutputStream outstream = sock.getOutputStream();
outstream.write(cmd.getBytes(UTF_8));
outstream.flush();
// this replicates NC - close the output stream before reading
if (!secure) {
// SSL prohibits unilateral half-close
sock.shutdownOutput();
}
reader = new BufferedReader(new InputStreamReader(sock.getInputStream()));
StringBuilder sb = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
sb.append(line).append("\n");
}
return sb.toString();
} catch (SocketTimeoutException e) {
throw new IOException("Exception while executing four letter word: " + cmd, e);
} finally {
if (sock != null) {
sock.close();
}
if (reader != null) {
reader.close();
}
}
}
public static void main(String[] args) throws IOException, SSLContextException {
if (args.length == 3) {
System.out.println(send4LetterWord(args[0], Integer.parseInt(args[1]), args[2]));
} else if (args.length == 4) {
System.out.println(send4LetterWord(args[0], Integer.parseInt(args[1]), args[2], Boolean.parseBoolean(args[3])));
} else {
System.out.println("Usage: FourLetterWordMain ");
}
}
}