Day094

README.adoc

@@ -3532,7 +3532,7 @@ public class Day093 {
     public static void main(String[] args) {
         List<String> myList = getList();
 
-        // If myList is null, a NullPointerException will be thrown
+//      If myList is null, a NullPointerException will be thrown
         for (String s : myList) {
             System.out.println(s);
         }
@@ -3554,4 +3554,62 @@ public class Day093 {
         return Instant.now().get(ChronoField.MILLI_OF_SECOND) % 2 == 0;
     }
 }
+----
+
+== Day 94 - Using Reactive Streams from Java 9
+[source,java]
+----
+package com.thegreatapi.ahundreddaysofjava.day094;
+
+import java.util.List;
+import java.util.concurrent.Flow;
+import java.util.concurrent.SubmissionPublisher;
+
+public class Day094 {
+
+    public static void main(String[] args) {
+        List<String> judasPriestMembers = List.of(
+                "Rob Halford",
+                "K.K. Downing",
+                "Glenn Tipton",
+                "Ian Hill",
+                "Scott Travis"
+        );
+
+        var subscriber = new MySubscriber();
+
+        try (var publisher = new SubmissionPublisher<String>()) {
+            publisher.subscribe(subscriber);
+            judasPriestMembers.forEach(publisher::submit);
+        }
+    }
+
+    static class MySubscriber implements Flow.Subscriber<String> {
+
+        private Flow.Subscription subscription;
+
+        @Override
+        public void onSubscribe(Flow.Subscription subscription) {
+            System.out.println("Started subscription");
+            this.subscription = subscription;
+            subscription.request(1);
+        }
+
+        @Override
+        public void onNext(String item) {
+            System.out.println(item);
+            subscription.request(1);
+        }
+
+        @Override
+        public void onError(Throwable throwable) {
+            System.err.println("Error: " + throwable);
+        }
+
+        @Override
+        public void onComplete() {
+            System.out.println("Subscription complete");
+        }
+    }
+}
 ----

days/day093/src/main/java/com/thegreatapi/ahundreddaysofjava/day093/Day093.java

@@ -9,7 +9,7 @@ public class Day093 {
     public static void main(String[] args) {
         List<String> myList = getList();
 
-        // If myList is null, a NullPointerException will be thrown
+//      If myList is null, a NullPointerException will be thrown
         for (String s : myList) {
             System.out.println(s);
         }

days/day094/pom.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>days</artifactId>
+        <groupId>com.thegreatapi.100daysofjava</groupId>
+        <version>1.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>day094</artifactId>
+
+    <properties>
+        <maven.compiler.source>16</maven.compiler.source>
+        <maven.compiler.target>16</maven.compiler.target>
+    </properties>
+
+</project>

days/day094/src/main/java/com/thegreatapi/ahundreddaysofjava/day094/Day094.java

@@ -0,0 +1,53 @@
+package com.thegreatapi.ahundreddaysofjava.day094;
+
+import java.util.List;
+import java.util.concurrent.Flow;
+import java.util.concurrent.SubmissionPublisher;
+
+public class Day094 {
+
+    public static void main(String[] args) {
+        List<String> judasPriestMembers = List.of(
+                "Rob Halford",
+                "K.K. Downing",
+                "Glenn Tipton",
+                "Ian Hill",
+                "Scott Travis"
+        );
+
+        var subscriber = new MySubscriber();
+
+        try (var publisher = new SubmissionPublisher<String>()) {
+            publisher.subscribe(subscriber);
+            judasPriestMembers.forEach(publisher::submit);
+        }
+    }
+
+    static class MySubscriber implements Flow.Subscriber<String> {
+
+        private Flow.Subscription subscription;
+
+        @Override
+        public void onSubscribe(Flow.Subscription subscription) {
+            System.out.println("Started subscription");
+            this.subscription = subscription;
+            subscription.request(1);
+        }
+
+        @Override
+        public void onNext(String item) {
+            System.out.println(item);
+            subscription.request(1);
+        }
+
+        @Override
+        public void onError(Throwable throwable) {
+            System.err.println("Error: " + throwable);
+        }
+
+        @Override
+        public void onComplete() {
+            System.out.println("Subscription complete");
+        }
+    }
+}

days/pom.xml

@@ -104,6 +104,7 @@
         <module>day091</module>
         <module>day092</module>
         <module>day093</module>
+        <module>day094</module>
     </modules>
 
 </project>