initial commit

natsio/subscriber/Dockerfile

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+FROM eclipse-temurin:21-jdk
+
+WORKDIR /app
+
+ADD https://repo1.maven.org/maven2/io/nats/jnats/2.16.14/jnats-2.16.14.jar nats.jar
+
+COPY Subscriber.java .
+
+RUN javac -cp nats.jar Subscriber.java
+
+CMD ["java", "-cp", ".:nats.jar", "Subscriber"]

natsio/subscriber/Subscriber.java

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+import io.nats.client.Connection;
+import io.nats.client.Dispatcher;
+import io.nats.client.Nats;
+
+public class Subscriber {
+  public static void main(String[] args) throws Exception {
+    Connection nc = Nats.connect("nats://nats:4222");
+
+    Dispatcher dispatcher = nc.createDispatcher(msg -> {
+      String received = new String(msg.getData()).trim();
+      String[] parts = received.split(",");
+      if (parts.length >= 2) {
+        int counter = Integer.parseInt(parts[0].trim());
+        long sendTime = Long.parseLong(parts[1].trim());
+        long latency = System.currentTimeMillis() - sendTime;
+
+        System.out.printf("Received: %d | Latency: %d ms%n", counter, latency);
+      }
+    });
+
+    dispatcher.subscribe("demo.subject");
+
+    Thread.sleep(Long.MAX_VALUE);
+  }
+}