logging doesn't work

Author: meowpunch

pom.xml

@@ -46,7 +46,21 @@
             <version>1.0.4</version>
         </dependency>
 
-
+        <dependency>
+            <groupId>org.apache.logging.log4j</groupId>
+            <artifactId>log4j-api</artifactId>
+            <version>2.18.0</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.logging.log4j</groupId>
+            <artifactId>log4j-core</artifactId>
+            <version>2.18.0</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.logging.log4j</groupId>
+            <artifactId>log4j-slf4j-impl</artifactId>
+            <version>2.18.0</version>
+        </dependency>
     </dependencies>
 
 </project>

src/main/java/concurrency/reactive/PubSub.java

@@ -0,0 +1,67 @@
+package concurrency.reactive;
+
+import java.util.stream.Stream;
+import org.reactivestreams.Publisher;
+import org.reactivestreams.Subscriber;
+import org.reactivestreams.Subscription;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class PubSub {
+
+  private static final Logger LOG = LoggerFactory.getLogger(PubSub.class.getName());
+
+  public static void main(String[] args) {
+
+    Publisher<Integer> pub = new Publisher<>() {
+      final Stream<Integer> intStream = Stream.iterate(0, i -> i + 1);
+
+      @Override
+      public void subscribe(Subscriber<? super Integer> subscriber) {
+        subscriber.onSubscribe(new Subscription() {
+          @Override
+          public void request(long n) {
+            try {
+              intStream.limit(n)
+                  .forEach(subscriber::onNext);
+            } catch (Exception e) {
+              subscriber.onError(e);
+            }
+
+            subscriber.onComplete();
+          }
+
+          @Override
+          public void cancel() {
+            LOG.info("noOp for cancel");
+          }
+        });
+      }
+    };
+
+    Subscriber<Integer> sub = new Subscriber<>() {
+      @Override
+      public void onSubscribe(Subscription subscription) {
+        LOG.info("onSubscribe");
+        subscription.request(10);
+      }
+
+      @Override
+      public void onNext(Integer integer) {
+        LOG.info("onNext: {}", integer);
+      }
+
+      @Override
+      public void onError(Throwable throwable) {
+        LOG.error("onError: {}", throwable);
+      }
+
+      @Override
+      public void onComplete() {
+        LOG.info("onComplete");
+      }
+    };
+
+    pub.subscribe(sub);
+  }
+}