added log

FlowClient/src/main/java/com/nisum/FlowApiBasicApplication.java

 package com.nisum;
-import lombok.extern.slf4j.Slf4j;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 
-@Slf4j
+
 @SpringBootApplication
 public class FlowApiBasicApplication {
 

FlowClient/src/main/java/com/nisum/MyController.java

@@ -19,7 +19,7 @@ public class MyController {
 
     @GetMapping("/home")
     public void getHome(){
-        System.out.println("Welcome home ....");
+        log.info("Welcome home ....");
     }
 
 

FlowClient/src/main/java/com/nisum/OrderSubscriber.java

 package com.nisum;
-
+import lombok.extern.slf4j.Slf4j;
 import java.util.concurrent.Flow;
 
+@Slf4j
 public class OrderSubscriber< T > implements Flow.Subscriber < T > {
     private Flow.Subscription subscription;
 
@@ -13,8 +14,8 @@ public class OrderSubscriber< T > implements Flow.Subscriber < T > {
 
     @Override
     public void onNext(T order) {
-        System.out.println("Subscriber :  " + Thread.currentThread().getName() + " ORDER " +order);
-        System.out.println("Received--ORDER::" + order);
+        log.info("Subscriber :  " + Thread.currentThread().getName() + " ORDER " +order);
+        log.info("Received--ORDER::" + order);
         subscription.request(1);
     }
 
@@ -25,6 +26,6 @@ public class OrderSubscriber< T > implements Flow.Subscriber < T > {
 
     @Override
     public void onComplete() {
-        System.out.println("ON COMPLETE ORDER");
+        log.info("ON COMPLETE ORDER");
     }
 }
\ No newline at end of file

FlowClient/src/main/java/com/nisum/ProductSubscriber.java

 package com.nisum;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 
+@Slf4j
 public class ProductSubscriber< T > implements Flow.Subscriber < T > {
     private Flow.Subscription subscription;
 
@@ -13,8 +16,8 @@ public class ProductSubscriber< T > implements Flow.Subscriber < T > {
 
     @Override
     public void onNext(T product) {
-        System.out.println("Subscriber :  " + Thread.currentThread().getName() + " PRODUCT " +product);
-        System.out.println("Received--PRODUCT::" + product);
+        log.info("Subscriber :  " + Thread.currentThread().getName() + " PRODUCT " +product);
+        log.info("Received--PRODUCT::" + product);
         subscription.request(1);
     }
 

FlowClient/src/main/java/com/nisum/service/FlowAppService.java

@@ -5,12 +5,14 @@ import com.nisum.OrderSubscriber;
 import com.nisum.ProductSubscriber;
 import com.nisum.model.Order;
 import com.nisum.model.Product;
+import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 import reactor.adapter.JdkFlowAdapter;
 import reactor.core.publisher.Flux;
 
 @Service
+@Slf4j
 public class FlowAppService {
 
     @Autowired
@@ -29,7 +31,7 @@ public class FlowAppService {
 
     public Flux<Order> getOrderUsingPublisher() throws InterruptedException {
         OrderSubscriber<Order> orderSubscriber = new OrderSubscriber<>();
-        System.out.println("Publishing OrderItems........................................................................");
+        log.info("Publishing OrderItems........................................................................");
         orderData=myServiceImpl.getAllOrdersFromService();
         JdkFlowAdapter.publisherToFlowPublisher(orderData).subscribe(orderSubscriber);
         Thread.sleep(1000);
@@ -38,7 +40,7 @@ public class FlowAppService {
 
     public Flux<Product> getProductsUsingPublisher() throws InterruptedException {
         ProductSubscriber<Product> productSubscriber = new ProductSubscriber<>();
-        System.out.println("Publishing ProductItems.....................................................................");
+        log.info("Publishing ProductItems.....................................................................");
         productData=myServiceImpl.getAllProductsFromService();
         JdkFlowAdapter.publisherToFlowPublisher(productData).subscribe(productSubscriber);
         Thread.sleep(1000);

Flow Api Basic Examples/build.gradle → Java-9-Flow-Api/build.gradle

@@ -14,6 +14,8 @@ repositories {
 
 dependencies {
 	implementation 'org.springframework.boot:spring-boot-starter-web'
+	compileOnly 'org.projectlombok:lombok'
+	annotationProcessor 'org.projectlombok:lombok'
 	testImplementation('org.springframework.boot:spring-boot-starter-test') {
 		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
 	}

Flow Api Basic Examples/src/main/java/com/nisum/backpressureStrategy/BackpressureSubscriber.java → Java-9-Flow-Api/src/main/java/com/nisum/backpressureStrategy/BackpressureSubscriber.java

 package com.nisum.backpressureStrategy;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 
+@Slf4j
 public class BackpressureSubscriber<Integer> implements Flow.Subscriber<Integer>{
 
     private Flow.Subscription subscription;
     @Override
     public void onSubscribe(Flow.Subscription subscription) {
-        System.out.println("Subscribed");
+        log.info("Subscribed");
         this.subscription = subscription;
         subscription.request(1);
     }
 
     @Override
     public void onNext(Integer item) {
-        System.out.println(Thread.currentThread().getName() + " | Received Inside Backpressure Subscriber = " + item);
+        log.info(Thread.currentThread().getName() + " | Received Inside Backpressure Subscriber = " + item);
         try {
             Thread.sleep(1000);
         } catch (InterruptedException e) {
@@ -25,12 +28,12 @@ public class BackpressureSubscriber<Integer> implements Flow.Subscriber<Integer>
 
     @Override
     public void onError(Throwable throwable) {
-        System.out.println(Thread.currentThread().getName() + " | ERROR = "
+        log.error(Thread.currentThread().getName() + " | ERROR = "
                 + throwable.getClass().getSimpleName() + " | " + throwable.getMessage());
     }
 
     @Override
     public void onComplete() {
-        System.out.println("Completed");
+        log.info("Completed");
     }
 }

Flow Api Basic Examples/src/main/java/com/nisum/backpressureStrategy/BackpressureUsingBufferStrategy.java → Java-9-Flow-Api/src/main/java/com/nisum/backpressureStrategy/BackpressureUsingBufferStrategy.java

 package com.nisum.backpressureStrategy;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 import java.util.concurrent.ForkJoinPool;
 import java.util.concurrent.SubmissionPublisher;
 
+@Slf4j
 public class BackpressureUsingBufferStrategy {
     public static void main(String[] args) throws InterruptedException {
 
@@ -14,7 +17,7 @@ public class BackpressureUsingBufferStrategy {
 
 
         for (int i = 0; i < 10; i++) {
-            System.out.println(Thread.currentThread().getName() + " Publishing = " + i);
+            log.info(Thread.currentThread().getName() + " Publishing = " + i);
             ((SubmissionPublisher<Integer>) backPressurePublisher).submit(i);
 
         }

Flow Api Basic Examples/src/main/java/com/nisum/backpressureStrategy/ElementSubscriber.java → Java-9-Flow-Api/src/main/java/com/nisum/backpressureStrategy/ElementSubscriber.java

 package com.nisum.backpressureStrategy;
-import java.util.concurrent.Flow;
-import java.util.stream.IntStream;
-
+import lombok.extern.slf4j.Slf4j;
 
+import java.util.concurrent.Flow;
 
+@Slf4j
 public class ElementSubscriber implements Flow.Subscriber<Integer> {
     private Flow.Subscription subscription;
     private int nextElementExpected;
@@ -24,25 +24,25 @@ public class ElementSubscriber implements Flow.Subscriber<Integer> {
        /* if (elementNumber != nextElementExpected) {
             IntStream.range(nextElementExpected, elementNumber).forEach(
                     (itemNumber) ->
-                            System.out.println(Thread.currentThread().getName()+"==="+"I missed the element " + itemNumber)
+                            log.info(Thread.currentThread().getName()+"==="+"I missed the element " + itemNumber)
             );
             nextElementExpected = elementNumber;
         }*/
-        System.out.println(Thread.currentThread().getName()+"==="+" I got a new element: " + elementNumber+" :Now wait till I give next Instruction");
+        log.info(Thread.currentThread().getName()+"==="+" I got a new element: " + elementNumber+" :Now wait till I give next Instruction");
         sleep();
         nextElementExpected++;
-        System.out.println(Thread.currentThread().getName()+"==="+"Get next element ");
+        log.info(Thread.currentThread().getName()+"==="+"Get next element ");
         subscription.request(1);
     }
 
     @Override
     public void onError(final Throwable throwable) {
-        System.out.println("Oops I got an error from the Publisher: " + throwable.getMessage());
+        log.error("Oops I got an error from the Publisher: " + throwable.getMessage());
     }
 
     @Override
     public void onComplete() {
-        System.out.println("Completed");
+        log.info("Completed");
     }
 
     private void sleep() {

Flow Api Basic Examples/src/main/java/com/nisum/backpressureStrategy/EndSubscriber.java → Java-9-Flow-Api/src/main/java/com/nisum/backpressureStrategy/EndSubscriber.java

 package com.nisum.backpressureStrategy;
+import lombok.extern.slf4j.Slf4j;
 
-import java.util.LinkedList;
-import java.util.List;
 import java.util.concurrent.Flow;
-import java.util.concurrent.atomic.AtomicInteger;
 
+@Slf4j
 public class EndSubscriber<T> implements Flow.Subscriber<T> {
 
     private Flow.Subscription subscription;
 
-
-
-
     @Override
     public void onSubscribe(Flow.Subscription subscription) {
         this.subscription = subscription;
@@ -21,7 +17,7 @@ public class EndSubscriber<T> implements Flow.Subscriber<T> {
     @Override
     public void onNext(T item) {
 
-        System.out.println("Got in End Subscriber : " + item );
+        log.info("Got in End Subscriber : " + item );
         try {
             Thread.sleep(1000);
         } catch (InterruptedException e) {
@@ -31,12 +27,12 @@ public class EndSubscriber<T> implements Flow.Subscriber<T> {
     }
     @Override
     public void onError(Throwable throwable) {
-        System.out.println(Thread.currentThread().getName() + " | ERROR = "
+        log.error(Thread.currentThread().getName() + " | ERROR = "
                 + throwable.getClass().getSimpleName() + " | " + throwable.getMessage());
     }
 
     @Override
     public void onComplete() {
-        System.out.println("Completed");
+        log.info("Completed");
     }
 }

Flow Api Basic Examples/src/main/java/com/nisum/backpressureStrategy/SubscriberEndBackpressreExample.java → Java-9-Flow-Api/src/main/java/com/nisum/backpressureStrategy/SubscriberEndBackpressreExample.java

 package com.nisum.backpressureStrategy;
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.SubmissionPublisher;
 
+@Slf4j
 public class SubscriberEndBackpressreExample {
     public static void main(String[] args) throws InterruptedException {
             SubmissionPublisher<Integer> sb=new SubmissionPublisher<>();
             sb.subscribe(new ElementSubscriber());
             for (int i = 0; i < 10; i++) {
-                System.out.println(Thread.currentThread().getName() + " Publishing = " + i);
+                log.info(Thread.currentThread().getName() + " Publishing = " + i);
                 sb.submit(i);
             }
             sb.close();

Flow Api Basic Examples/src/main/java/com/nisum/basicFlowExampleUsingProcessor/MySubscriber.java → Java-9-Flow-Api/src/main/java/com/nisum/basicFlowExampleUsingProcessor/MySubscriber.java

 package com.nisum.basicFlowExampleUsingProcessor;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 
+@Slf4j
 public class MySubscriber < T > implements Flow.Subscriber < T > {
     private Flow.Subscription subscription;
 
@@ -13,8 +16,8 @@ public class MySubscriber < T > implements Flow.Subscriber < T > {
 
     @Override
     public void onNext(T item) {
-        System.out.println("Subscriber :  " + Thread.currentThread().getName() + " item " + item);
-        System.out.println("Received::" + item);
+        log.info("Subscriber :  " + Thread.currentThread().getName() + " item " + item);
+        log.info("Received::" + item);
         subscription.request(1);
     }
 
@@ -25,6 +28,6 @@ public class MySubscriber < T > implements Flow.Subscriber < T > {
 
     @Override
     public void onComplete() {
-        System.out.println("Done");
+        log.info("Done");
     }
 }
\ No newline at end of file

Flow Api Basic Examples/src/main/java/com/nisum/processors/App.java → Java-9-Flow-Api/src/main/java/com/nisum/processors/App.java

 package com.nisum.processors;
-
 import com.nisum.basicFlowExampleUsingProcessor.MySubscriber;
-import com.nisum.processors.MyFilterProcessor;
-import com.nisum.processors.MyTransformProcessor;
-
+import lombok.extern.slf4j.Slf4j;
 
 import java.util.Arrays;
 import java.util.concurrent.SubmissionPublisher;
 
+@Slf4j
 public class App {
 
    public static void main(String[] args) throws InterruptedException {
@@ -29,7 +27,7 @@ public class App {
        filterProcessor.subscribe(transformProcessor);
        transformProcessor.subscribe(subscriber);
 
-       System.out.println("Publishing Items...");
+       log.info("Publishing Items...");
 
        String[] items = {"100", "x", "200", "x", "300", "x"};
        Arrays.asList(items).stream().forEach(i -> publisher.submit(i));

Flow Api Basic Examples/src/main/java/com/nisum/processors/MyFilterProcessor.java → Java-9-Flow-Api/src/main/java/com/nisum/processors/MyFilterProcessor.java

 package com.nisum.processors;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 import java.util.concurrent.SubmissionPublisher;
 import java.util.function.Predicate;
 
+@Slf4j
 public   class   MyFilterProcessor < T, R >   extends SubmissionPublisher<R> implements Flow.Processor< T , R > {
 
     private Predicate<T> predicate;
@@ -21,7 +24,7 @@ public   class   MyFilterProcessor < T, R >   extends SubmissionPublisher<R> imp
     }
 
     public void onNext(T item) {
-        System.out.println("Filter Processor:  " + Thread.currentThread().getName() + " item " + item);
+        log.info("Filter Processor:  " + Thread.currentThread().getName() + " item " + item);
         if (predicate.test(item)) {
             submit((R) item);
         }

Flow Api Basic Examples/src/main/java/com/nisum/processors/MyTransformProcessor.java → Java-9-Flow-Api/src/main/java/com/nisum/processors/MyTransformProcessor.java

 package com.nisum.processors;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 import java.util.concurrent.SubmissionPublisher;
 import java.util.function.Function;
 
+@Slf4j
 public class MyTransformProcessor<T,R> extends SubmissionPublisher<R> implements Flow.Processor<T, R> {
 
     private Function function;
@@ -22,7 +25,7 @@ public class MyTransformProcessor<T,R> extends SubmissionPublisher<R> implements
 
     @Override
     public void onNext(T item) {
-        System.out.println("Transform Processor:  " + Thread.currentThread().getName() + " item " + item);
+        log.info("Transform Processor:  " + Thread.currentThread().getName() + " item " + item);
         submit((R) function.apply(item));
         subscription.request(1);
     }

Flow Api Basic Examples/src/main/java/com/nisum/publishers/SimplePublisherMain.java → Java-9-Flow-Api/src/main/java/com/nisum/publishers/SimplePublisherMain.java

 package com.nisum.publishers;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 
+@Slf4j
 public class SimplePublisherMain {
     public static void main(String[] args) {
         new SimplePublisher(10).subscribe(new Flow.Subscriber<>() {
@@ -10,14 +13,14 @@ public class SimplePublisherMain {
             }
             @Override
             public void onNext(Integer item) {
-                System.out.println("item = [" + item + "]");
+                log.info("item = [" + item + "]");
             }
             @Override
             public void onError(Throwable throwable) {
             }
             @Override
             public void onComplete() {
-                System.out.println("complete");
+                log.info("complete");
             }
         });
     }

Flow Api Basic Examples/src/main/java/com/nisum/publishers/SubmissionPublisherConsumeMethod.java → Java-9-Flow-Api/src/main/java/com/nisum/publishers/SubmissionPublisherConsumeMethod.java

 package com.nisum.publishers;
 
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.*;
 
+@Slf4j
 public class SubmissionPublisherConsumeMethod {
 
     public static void main(String[] args) throws InterruptedException {
@@ -13,7 +16,7 @@ public class SubmissionPublisherConsumeMethod {
         });
         Thread.sleep(13000);
         submissionPublisher.close();
-        System.out.println("Status::"+status);
+        log.info("Status::"+status);
 
     }
 

Flow Api Basic Examples/src/main/java/com/nisum/publishers/SubmissionPublisherOfferMethod.java → Java-9-Flow-Api/src/main/java/com/nisum/publishers/SubmissionPublisherOfferMethod.java

 package com.nisum.publishers;
 
 import com.nisum.subscribers.CustomerSubscriber;
+import lombok.extern.slf4j.Slf4j;
 
 import java.util.concurrent.ForkJoinPool;
 import java.util.concurrent.SubmissionPublisher;
 
+@Slf4j
 public class SubmissionPublisherOfferMethod {
     public static void main(String[] args) throws InterruptedException {
 

Flow Api Basic Examples/src/main/java/com/nisum/sampleCode/Sample.java → Java-9-Flow-Api/src/main/java/com/nisum/sampleCode/Sample.java

@@ -2,12 +2,13 @@ package com.nisum.sampleCode;
 
 import com.nisum.subscribers.MagazineSubscriber;
 import com.nisum.subscribers.PrintSubscriber;
+import lombok.extern.slf4j.Slf4j;
 
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.SubmissionPublisher;
 
 
-
+@Slf4j
 public class Sample {
     public static void main(String[] args) throws InterruptedException, ExecutionException {
 
@@ -17,7 +18,7 @@ public class Sample {
         feed.subscribe(magazineSubscriber);
         feed.subscribe(printSubscriber);
         for (int i = 0; i < 10; i++) {
-            System.out.println(Thread.currentThread().getName() + " Publishing = " + i);
+            log.info(Thread.currentThread().getName() + " Publishing = " + i);
             feed.submit(i);
             Thread.sleep(1000);
         }

Flow Api Basic Examples/src/main/java/com/nisum/subscribers/CustomerSubscriber.java → Java-9-Flow-Api/src/main/java/com/nisum/subscribers/CustomerSubscriber.java

 package com.nisum.subscribers;
 
+
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 
-    public class CustomerSubscriber<Integer> implements Flow.Subscriber<Integer> {
+@Slf4j
+public class CustomerSubscriber<Integer> implements Flow.Subscriber<Integer> {
 
     private Flow.Subscription sub;
 
     @Override
     public void onSubscribe(Flow.Subscription sub) {
-        System.out.println("Subscription done");
+        log.info("Subscription done");
         this.sub = sub;
         sub.request(5);
     }
@@ -16,7 +20,7 @@ import java.util.concurrent.Flow;
 
     @Override
     public void onNext(Integer arg0) {
-        System.out.println("Got in Customer Subscriber : " + arg0 );
+        log.info("Got in Customer Subscriber : " + arg0 );
         try {
             Thread.sleep(1000);
         } catch (InterruptedException e) {
@@ -33,7 +37,7 @@ import java.util.concurrent.Flow;
 
     @Override
     public void onComplete() {
-        System.out.println("onComplete");
+        log.info("onComplete");
     }
 
 

Flow Api Basic Examples/src/main/java/com/nisum/subscribers/EventSubscriber.java → Java-9-Flow-Api/src/main/java/com/nisum/subscribers/EventSubscriber.java

 package com.nisum.subscribers;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 
+@Slf4j
 public class EventSubscriber<Integer> implements Flow.Subscriber<Integer> {
 
     private Flow.Subscription subscription;
@@ -13,7 +16,7 @@ public class EventSubscriber<Integer> implements Flow.Subscriber<Integer> {
 
     @Override
     public void onNext(Integer item) {
-        System.out.println("ES ::"+item);
+        log.info("ES ::"+item);
         subscription.request(1);
         if(item.equals(3))
             subscription.cancel();
@@ -21,12 +24,12 @@ public class EventSubscriber<Integer> implements Flow.Subscriber<Integer> {
 
     @Override
     public void onError(Throwable throwable) {
-        System.out.println("ERROR "+throwable);
+        log.error("ERROR "+throwable);
     }
 
     @Override
     public void onComplete() {
-        System.out.println("DONE");
+        log.info("DONE");
     }
 }
 

Flow Api Basic Examples/src/main/java/com/nisum/subscribers/MagazineSubscriber.java → Java-9-Flow-Api/src/main/java/com/nisum/subscribers/MagazineSubscriber.java

 package com.nisum.subscribers;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 
+@Slf4j
 public class MagazineSubscriber<Integer> implements Flow.Subscriber<Integer> {
 
     private Flow.Subscription subscription;
@@ -13,7 +16,7 @@ public class MagazineSubscriber<Integer> implements Flow.Subscriber<Integer> {
     }
     @Override
     public void onNext(Integer item) {
-        System.out.println(Thread.currentThread().getName() +"Magazine  ::" + item);
+        log.info(Thread.currentThread().getName() +"Magazine  ::" + item);
         subscription.request(1);
         if(item.equals(5))
             subscription.cancel();
@@ -21,10 +24,10 @@ public class MagazineSubscriber<Integer> implements Flow.Subscriber<Integer> {
     }
     @Override
     public void onError(Throwable error) {
-        System.out.println("RECEIVED AN ERROR IN MAGAZINE SUBSCRIBER: " + error.getMessage());
+        log.error("RECEIVED AN ERROR IN MAGAZINE SUBSCRIBER: " + error.getMessage());
     }
     @Override
     public void onComplete() {
-        System.out.println("MagazineSubscription is complete");
+        log.info("MagazineSubscription is complete");
     }
 }

Flow Api Basic Examples/src/main/java/com/nisum/subscribers/MessageSubscriber.java → Java-9-Flow-Api/src/main/java/com/nisum/subscribers/MessageSubscriber.java

 package com.nisum.subscribers;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 
+@Slf4j
 public class MessageSubscriber<Integer> implements Flow.Subscriber<Integer> {
 
     private Flow.Subscription subscription;
@@ -9,13 +12,13 @@ public class MessageSubscriber<Integer> implements Flow.Subscriber<Integer> {
     @Override
     public void onSubscribe(Flow.Subscription subscription) {
         this.subscription=subscription;
-        System.out.println("Subscription done");
+        log.info("Subscription done");
         subscription.request(1);
     }
 
     @Override
     public void onNext(Integer item) {
-        System.out.println(Thread.currentThread().getName() + "MS ::"+item);
+        log.info(Thread.currentThread().getName() + "MS ::"+item);
         try {
             Thread.sleep(2000);
         } catch (InterruptedException e) {
@@ -27,11 +30,11 @@ public class MessageSubscriber<Integer> implements Flow.Subscriber<Integer> {
     @Override
     public void onError(Throwable throwable) {
 
-        System.out.println("RECEIVED AN ERROR IN MESSAGE SUBSCRIBER:::"+throwable);
+        log.error("RECEIVED AN ERROR IN MESSAGE SUBSCRIBER:::"+throwable);
     }
 
     @Override
     public void onComplete() {
-        System.out.println("DONE");
+        log.info("DONE");
     }
 }

Flow Api Basic Examples/src/main/java/com/nisum/subscribers/PrintSubscriber.java → Java-9-Flow-Api/src/main/java/com/nisum/subscribers/PrintSubscriber.java

 package com.nisum.subscribers;
 
+import lombok.extern.slf4j.Slf4j;
+
 import java.util.concurrent.Flow;
 
+@Slf4j
 public class PrintSubscriber<Integer> implements Flow.Subscriber<Integer> {
 
     private Flow.Subscription subscription;
@@ -13,16 +16,16 @@ public class PrintSubscriber<Integer> implements Flow.Subscriber<Integer> {
     }
     @Override
     public void onNext(Integer item) {
-        System.out.println(Thread.currentThread().getName() +":Print ::" + item);
+        log.info(Thread.currentThread().getName() +":Print ::" + item);
         subscription.request(1);
     }
 
     @Override
     public void onError(Throwable error) {
-        System.out.println("RECEIVED AN ERROR IN PRINT SUBSCRIBER: " + error.getMessage());
+        log.error("RECEIVED AN ERROR IN PRINT SUBSCRIBER: " + error.getMessage());
     }
     @Override
     public void onComplete() {
-        System.out.println("PrintSubscriber is complete");
+        log.info("PrintSubscriber is complete");
     }
 }

Flow Api Basic Examples/src/main/java/com/nisum/subscriptions/SubscriptionBehaviour.java → Java-9-Flow-Api/src/main/java/com/nisum/subscriptions/SubscriptionBehaviour.java

@@ -16,9 +16,6 @@ public class SubscriptionBehaviour {
         sleep(1000);
     }
 
-
-
-
     private static Boolean sleep(int ms) {
         try{
             Thread.sleep(ms);

web-service/src/main/java/com/nisum/model/Order.java

@@ -15,5 +15,5 @@ public class Order {
     private int orderId;
     private String orderName;
     private List<Product> products;
-    //private int productCount=products.size();
+
 }