/*
 * 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.jmeter.util;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

import org.apache.jmeter.JMeter;


/**
 * Simple utility to send a shutdown message to a non-GUI instance of JMeter
 */
public class ShutdownClient {
    public static void main(String[] args) throws IOException {
        int port = JMeter.UDP_PORT_DEFAULT;
        if (args.length > 1){
            port = Integer.parseInt(args[1]);
        } else if (args.length == 0) {
            throw new RuntimeException("Usage: command [port]");
        }
        String command = args[0];
        System.out.println("Sending "+command+" request to port "+port);
        DatagramSocket socket = new DatagramSocket();
        byte[] buf = command.getBytes("ASCII");
        InetAddress address = InetAddress.getByName("localhost");
        DatagramPacket packet = new DatagramPacket(buf, buf.length, address, port);
        socket.send(packet);
        socket.close();
    }
}

/*
 * 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.jmeter.util;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

import org.apache.jmeter.JMeter;


/**
 * Simple utility to send a shutdown message to a non-GUI instance of JMeter
 */
public class ShutdownClient {
    public static void main(String[] args) throws IOException {
        int port = JMeter.UDP_PORT_DEFAULT;
        if (args.length > 1){
            port = Integer.parseInt(args[1]);
        } else if (args.length == 0) {
            throw new RuntimeException("Usage: command [port]");
        }
        String command = args[0];
        System.out.println("Sending "+command+" request to port "+port);
        try (DatagramSocket socket = new DatagramSocket()) {
            byte[] buf = command.getBytes("ASCII");
            InetAddress address = InetAddress.getByName("localhost");
            DatagramPacket packet = new DatagramPacket(buf, buf.length, address,
                    port);
            socket.send(packet);
        }
    }
}

Use try-with statement to close socket.