Azure IoT SDK message status is set to SUCCESS when in the queue

BugStatusIsCompletedBeforeCompletion.java

// BugStatusIsCompletedBeforeCompletion.java

import com.microsoft.azure.iot.service.sdk.*;
import java.nio.charset.StandardCharsets;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.time.Instant;
import java.util.Date;
import java.util.UUID;

public class BugStatusIsCompletedBeforeCompletion
{
    static String hub = System.getenv("SDK_HUB_NAME");
    static String serviceKey = System.getenv("SDK_SERVICE_KEY");
    static String device = System.getenv("SDK_DEVICE_ID");
    static String deviceKey = System.getenv("SDK_DEVICE_KEY");

    static MessageReceiver receiver;

    public static void main(String[] args)
    {
        String messageId1 = UUID.randomUUID().toString();
        String messageId2 = UUID.randomUUID().toString();

        try
        {
            // Exercise 1
            send(messageId1);
            checkFeedback(messageId1);

            // Exercise 2
            startReceiver();
            send(messageId2);
            Thread.sleep(5000);
            checkFeedback(messageId2);
            stopReceiver();
        }
        catch (Exception e)
        {
            log("Sender exception: " + e);
            System.exit(-1);
        }

        log("Done");
    }

    static void send(String messageId) throws Exception
    {
        Message msg = new Message("test".getBytes(StandardCharsets.UTF_8));
        msg.setTo(device);
        msg.setDeliveryAcknowledgement(DeliveryAcknowledgement.Full);
        msg.setExpiryTimeUtc(Date.from(Instant.now().plusSeconds(86400)));
        msg.setMessageId(messageId);

        String cs = "HostName=" + hub + ".azure-devices.net;SharedAccessKeyName=service;SharedAccessKey=" + serviceKey;

        log("Creating sender client");
        ServiceClient client = ServiceClient.createFromConnectionString(cs, IotHubServiceClientProtocol.AMQPS);

        log("Open sender connection");
        client.open();

        log("Sending message, Content: " + new String(msg.getBytes()) + ", ID: " + msg.getMessageId());
        client.send(device, msg);
    }

    static void checkFeedback(String messageId) throws Exception
    {
        String cs = "HostName=" + hub + ".azure-devices.net;SharedAccessKeyName=service;SharedAccessKey=" + serviceKey;

        log("Creating feedback receiver client");
        ServiceClient client = ServiceClient.createFromConnectionString(cs, IotHubServiceClientProtocol.AMQPS);
        FeedbackReceiver feedbackReceiver = client.getFeedbackReceiver(device);

        log("Open feedback receiver connection");
        feedbackReceiver.open();

        log("Checking the status of the message...");
        boolean found = false;
        while (!found)
        {
            log("Retrieving feedback batch...");
            FeedbackBatch batch = feedbackReceiver.receive(10000);

            log("Found feedback batch, size " + batch.getRecords().size());
            for (FeedbackRecord record : batch.getRecords())
            {
                log("Batch record " + record.getOriginalMessageId());
                if (record.getOriginalMessageId().equals(messageId))
                {
                    found = true;
                    log("Message " + messageId + " feedback found: description = " + record.getDescription() + "; status code = " + record.getStatusCode());
                }
            }
        }

        log("Close feedback receiver connection");
        feedbackReceiver.close();
        client.close();
    }

    static void startReceiver()
    {
        receiver = new MessageReceiver(hub, device, deviceKey, true);
        receiver.start();
    }

    static void stopReceiver() throws Exception
    {
        receiver.close();
    }

    static void log(String text)
    {
        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss.SSS");
        System.out.println("[" + dateFormat.format(new Date()) + "] " + text);
    }
}

// MessageReceiver.java

import com.microsoft.azure.iothub.DeviceClient;
import com.microsoft.azure.iothub.IotHubClientProtocol;
import com.microsoft.azure.iothub.IotHubMessageResult;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

public class MessageReceiver extends Thread
{
    private final boolean hideBug990;
    private String hub;
    private String device;
    private String deviceKey;
    private DeviceClient client;

    public MessageReceiver(String hub, String device, String deviceKey, boolean hideBug990)
    {
        this.hub = hub;
        this.device = device;
        this.deviceKey = deviceKey;
        this.hideBug990 = hideBug990;
    }

    public class MessageCallback implements com.microsoft.azure.iothub.MessageCallback
    {
        public IotHubMessageResult execute(com.microsoft.azure.iothub.Message msg, Object hideBug990)
        {
            if ((boolean) hideBug990)
                log("Message received: Content: " + new String(msg.getBytes()) + ", ID: " + msg.getProperty("messageId"));
            else
                log("Message received: Content: " + new String(msg.getBytes()) + ", ID: " + msg.getMessageId() + ", msg prop: " + msg.getProperty("messageId"));

            log("Changing the status of the message to COMPLETE");
            return IotHubMessageResult.COMPLETE;
        }
    }

    public void run()
    {
        try
        {
            String cs = "HostName=" + this.hub + ".azure-devices.net;DeviceId=" + this.device + ";SharedAccessKey=" + this.deviceKey;

            log("Creating message receiver client");
            this.client = new DeviceClient(cs, IotHubClientProtocol.AMQPS);
            this.client.setMessageCallback(new MessageCallback(), this.hideBug990);

            log("Opening message receiver connection");
            this.client.open();
        }
        catch (Exception e)
        {
            log("Message receiver exception: " + e);
            System.exit(-1);
        }
    }

    public void close() throws Exception
    {
        log("Closing message receiver");
        this.client.close();
    }

    static void log(String text)
    {
        DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss.SSS");
        System.out.println("[" + dateFormat.format(new Date()) + "] " + text);
    }
}