ApsaraMQ for RocketMQ:Send messages by using multiple threads

Producer producer = ONSFactory.createProducer(properties);
producer.start();

// Thread 1 and Thread 2 share the same producer
Thread t1 = new Thread(() -> producer.send(msg1));
Thread t2 = new Thread(() -> producer.send(msg2));
t1.start();
t2.start();

// Each thread creates its own producer -- wastes resources
Thread t1 = new Thread(() -> {
    Producer p = ONSFactory.createProducer(properties);
    p.start();
    p.send(msg);
    p.shutdown();
});

import com.aliyun.openservices.ons.api.Message;
import com.aliyun.openservices.ons.api.Producer;
import com.aliyun.openservices.ons.api.ONSFactory;
import com.aliyun.openservices.ons.api.PropertyKeyConst;
import com.aliyun.openservices.ons.api.SendResult;
import java.util.Properties;

public class SharedProducer {
    public static void main(String[] args) {
        Properties properties = new Properties();
        // The ID of the consumer group created in the ApsaraMQ for RocketMQ console.
        properties.put(PropertyKeyConst.GROUP_ID, "<your-group-id>");
        // Make sure the environment variables ALIBABA_CLOUD_ACCESS_KEY_ID
        // and ALIBABA_CLOUD_ACCESS_KEY_SECRET are configured.
        properties.put(PropertyKeyConst.AccessKey, System.getenv("ALIBABA_CLOUD_ACCESS_KEY_ID"));
        properties.put(PropertyKeyConst.SecretKey, System.getenv("ALIBABA_CLOUD_ACCESS_KEY_SECRET"));
        // Message send timeout in milliseconds.
        properties.setProperty(PropertyKeyConst.SendMsgTimeoutMillis, "3000");
        // TCP endpoint. Get this value from the TCP endpoint section on the Instance Details
        // page in the ApsaraMQ for RocketMQ console.
        properties.put(PropertyKeyConst.NAMESRV_ADDR, "<your-tcp-endpoint>");

        final Producer producer = ONSFactory.createProducer(properties);
        // Call start() once before sending any messages.
        producer.start();

        // Both threads share the same producer instance.
        Thread thread1 = new Thread(() -> {
            try {
                Message msg = new Message(
                    "TopicTestMQ",   // Topic for normal messages
                    "TagA",          // Message tag for consumer-side filtering
                    "Hello MQ".getBytes()  // Message body in binary format
                );
                SendResult result = producer.send(msg);
                if (result != null) {
                    System.out.println("Sent successfully. Message ID: " + result.getMessageId());
                }
            } catch (Exception e) {
                // Handle failures: retry or persist the message for later processing.
                e.printStackTrace();
            }
        });

        Thread thread2 = new Thread(() -> {
            try {
                Message msg = new Message("TopicTestMQ", "TagA", "Hello MQ".getBytes());
                SendResult result = producer.send(msg);
                if (result != null) {
                    System.out.println("Sent successfully. Message ID: " + result.getMessageId());
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        });

        thread1.start();
        thread2.start();

        // Call shutdown() when the producer is no longer needed to release resources.
        // producer.shutdown();
    }
}