Stopping a JMeter non-gui test that started from Java code

Question

I started a JMeter JMX test from Java code:

StandardJMeterEngine jmeter = new StandardJMeterEngine();
..
jmeter.configure(testPlanTree);
jmeter.run();

I would like to be able to stop the test (from outside the test, for example command line), similar to the option if it had run from non-gui mode using (from cmd):

jmeter -n -t MyTest.jmx

Stopping with:

shutdown.cmd (/sh)
stoptest.cmd (/sh)

When starting from non-gui cmd, I can see that it waits for signals:

Waiting for possible shutdown message on port 4445

If started from my non-gui Java code, it does not listen on this port. How can I add this functionality to this mode?

Any suggestion will be very appreciated? Thanks!

Answer 1

I would suggest looking into JMeter.java source code, especially at the following method:

private static void waitForSignals(final List<JMeterEngine> engines, DatagramSocket socket) 

It contains everything you need to implement the functionality you require.

Just in case, here is an example code listing, just replace path to JMeter and test script files with your own ones:

import org.apache.jmeter.engine.JMeterEngine;
import org.apache.jmeter.engine.StandardJMeterEngine;
import org.apache.jmeter.save.SaveService;
import org.apache.jmeter.util.JMeterUtils;
import org.apache.jorphan.collections.HashTree;
import org.apache.jorphan.logging.LoggingManager;
import org.apache.jorphan.util.HeapDumper;
import org.apache.log.Logger;

import java.io.File;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.util.ArrayList;
import java.util.List;


public class JMeterFromExistingJMX {

    private static final Logger log = LoggingManager.getLoggerForClass();

    public static void main(String[] argv) throws Exception {
        // JMeter Engine
        final StandardJMeterEngine jmeter = new StandardJMeterEngine();

        // Initialize Properties, logging, locale, etc.
        JMeterUtils.loadJMeterProperties("/opt/jmeter/bin/jmeter.properties");
        JMeterUtils.setJMeterHome("/opt/jmeter");
        JMeterUtils.initLogging();// you can comment this line out to see extra log messages of i.e. DEBUG level
        JMeterUtils.initLocale();

        // Initialize JMeter SaveService
        SaveService.loadProperties();

        HashTree testPlanTree = SaveService.loadTree(new File("/opt/jmeter/bin/test.jmx"));

        final List<JMeterEngine> engines = new ArrayList<>();
        engines.add(jmeter);

        int port = JMeterUtils.getPropDefault("jmeterengine.nongui.port", 4445); // $NON-NLS-1$
        int maxPort = JMeterUtils.getPropDefault("jmeterengine.nongui.maxport", 4455); // $NON-NLS-1$
        if (port > 1000) {
            final DatagramSocket socket = getSocket(port, maxPort);
            if (socket != null) {
                Thread waiter = new Thread("UDP Listener") {
                    @Override
                    public void run() {
                        waitForSignals(engines, socket);
                    }
                };
                waiter.setDaemon(true);
                waiter.start();
            } else {
                System.out.println("Failed to create UDP port");
            }
        }

        // Run JMeter Test
        jmeter.configure(testPlanTree);
        jmeter.run();
    }

    private static void waitForSignals(final List<JMeterEngine> engines, DatagramSocket socket) {
        byte[] buf = new byte[80];
        System.out.println("Waiting for possible Shutdown/StopTestNow/Heapdump message on port " + socket.getLocalPort());
        DatagramPacket request = new DatagramPacket(buf, buf.length);
        try {
            while (true) {
                socket.receive(request);
                InetAddress address = request.getAddress();
                // Only accept commands from the local host
                if (address.isLoopbackAddress()) {
                    String command = new String(request.getData(), request.getOffset(), request.getLength(), "ASCII");
                    System.out.println("Command: " + command + " received from " + address);
                    log.info("Command: " + command + " received from " + address);
                    switch (command) {
                        case "StopTestNow":
                            for (JMeterEngine engine : engines) {
                                engine.stopTest(true);
                            }
                            break;
                        case "Shutdown":
                            for (JMeterEngine engine : engines) {
                                engine.stopTest(false);
                            }
                            break;
                        case "HeapDump":
                            HeapDumper.dumpHeap();
                            break;
                        default:
                            System.out.println("Command: " + command + " not recognised ");
                            break;
                    }
                }
            }
        } catch (Exception e) {
            log.error("Error", e);
        } finally {
            socket.close();
        }
    }

    private static DatagramSocket getSocket(int udpPort, int udpPortMax) {
        DatagramSocket socket = null;
        int i = udpPort;
        while (i <= udpPortMax) {
            try {
                socket = new DatagramSocket(i);
                break;
            } catch (SocketException e) {
                i++;
            }
        }

        return socket;
    }
}

Check out Five Ways To Launch a JMeter Test without Using the JMeter GUI for more information and examples