/**
* 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.oncrpc;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.util.Arrays;
/**
* A simple UDP based RPC client which just sends one request to a server.
*/
public class SimpleUdpClient {
protected final String host;
protected final int port;
protected final XDR request;
protected final boolean oneShot;
public SimpleUdpClient(String host, int port, XDR request) {
this(host, port, request, true);
}
public SimpleUdpClient(String host, int port, XDR request, Boolean oneShot) {
this.host = host;
this.port = port;
this.request = request;
this.oneShot = oneShot;
}
public void run() throws IOException {
DatagramSocket clientSocket = new DatagramSocket();
InetAddress IPAddress = InetAddress.getByName(host);
byte[] sendData = request.getBytes();
byte[] receiveData = new byte[65535];
DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length,
IPAddress, port);
clientSocket.send(sendPacket);
DatagramPacket receivePacket = new DatagramPacket(receiveData,
receiveData.length);
clientSocket.receive(receivePacket);
// Check reply status
XDR xdr = new XDR();
xdr.writeFixedOpaque(Arrays.copyOfRange(receiveData, 0,
receivePacket.getLength()));
RpcReply reply = RpcReply.read(xdr);
if (reply.getState() != RpcReply.ReplyState.MSG_ACCEPTED) {
throw new IOException("Request failed: " + reply.getState());
}
clientSocket.close();
}
}