BAEL-2354 - An Introduction to the Event Notification Model in CDI 2.0 (#5685)

* Initial Commit

* Update pom.xml

* Update pom.xml

* Update LowercaseTextServiceUnitTest.java

* Update UppercaseTextServiceUnitTest.java

* Delete TextApplication.java

* Update source files

* Update BootstrappingApplication.java

* Add AnotherSimpleEventObserver class

* Rename event classes

* Update ExampleEventSource.java

* Update UppercaseTextService.java

* Delete TextService.java

* Delete LowercaseTextService.java

* Delete LowercaseTextServiceUnitTest.java

* Delete UppercaseTextServiceUnitTest.java

* Fixed text service unit test

* Update TextService.java

cdi/pom.xml

@@ -5,7 +5,7 @@
     <groupId>com.baeldung</groupId>
     <artifactId>cdi</artifactId>
     <version>1.0-SNAPSHOT</version>
-
+    
     <parent>
         <groupId>com.baeldung</groupId>
         <artifactId>parent-spring-4</artifactId>
@@ -14,6 +14,16 @@
     </parent>
 
     <dependencies>
+        <dependency>
+            <groupId>javax.enterprise</groupId>
+            <artifactId>cdi-api</artifactId>
+            <version>${cdi-api.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.jboss.weld.se</groupId>
+            <artifactId>weld-se-core</artifactId>
+            <version>${weld-se-core.version}</version>
+        </dependency>  
         <dependency>
             <groupId>org.hamcrest</groupId>
             <artifactId>hamcrest-core</artifactId>
@@ -42,11 +52,6 @@
             <artifactId>aspectjweaver</artifactId>
             <version>${aspectjweaver.version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.jboss.weld.se</groupId>
-            <artifactId>weld-se-core</artifactId>
-            <version>${weld-se-core.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-test</artifactId>
@@ -54,13 +59,13 @@
             <scope>test</scope>
         </dependency>
     </dependencies>
-
     <properties>
-        <aspectjweaver.version>1.8.9</aspectjweaver.version>
-        <weld-se-core.version>2.4.1.Final</weld-se-core.version>
+        <cdi-api.version>2.0.SP1</cdi-api.version>
+        <weld-se-core.version>3.0.5.Final</weld-se-core.version>
+        <aspectjweaver.version>1.9.2</aspectjweaver.version>
         <hamcrest-core.version>1.3</hamcrest-core.version>
         <assertj-core.version>3.10.0</assertj-core.version>
         <junit.version>4.12</junit.version>
+        <spring.version>5.1.2.RELEASE</spring.version>
     </properties>
-
 </project>

cdi/src/main/java/com/baeldung/cdi2observers/application/BootstrappingApplication.java

@@ -0,0 +1,15 @@
+package com.baeldung.cdi.cdi2observers.application;
+
+import com.baeldung.cdi.cdi2observers.events.ExampleEvent;
+import javax.enterprise.inject.se.SeContainer;
+import javax.enterprise.inject.se.SeContainerInitializer;
+
+public class BootstrappingApplication {
+    
+    public static void main(String... args) {
+        SeContainerInitializer containerInitializer = SeContainerInitializer.newInstance();
+        try (SeContainer container = containerInitializer.initialize()) {
+            container.getBeanManager().fireEvent(new ExampleEvent("Welcome to Baeldung!"));
+        }
+    }
+}

cdi/src/main/java/com/baeldung/cdi2observers/events/ExampleEvent.java

@@ -0,0 +1,14 @@
+package com.baeldung.cdi.cdi2observers.events;
+
+public class ExampleEvent {
+    
+   private final String eventMessage;
+
+    public ExampleEvent(String eventMessage) {
+        this.eventMessage = eventMessage;
+    }
+    
+    public String getEventMessage() {
+        return eventMessage;
+    }
+}

cdi/src/main/java/com/baeldung/cdi2observers/events/ExampleEventSource.java

@@ -0,0 +1,14 @@
+package com.baeldung.cdi.cdi2observers.events;
+
+import javax.enterprise.event.Event;
+import javax.inject.Inject;
+
+public class ExampleEventSource {
+    
+    @Inject
+    Event<ExampleEvent> exampleEvent;
+    
+    public void fireEvent() {
+        exampleEvent.fireAsync(new ExampleEvent("Welcome to Baeldung!"));
+    }   
+}

cdi/src/main/java/com/baeldung/cdi2observers/observers/AnotherExampleEventObserver.java

@@ -0,0 +1,12 @@
+package com.baeldung.cdi.cdi2observers.observers;
+
+import com.baeldung.cdi.cdi2observers.events.ExampleEvent;
+import javax.annotation.Priority;
+import javax.enterprise.event.Observes;
+
+public class AnotherExampleEventObserver {
+    
+    public String onEvent(@Observes @Priority(2) ExampleEvent event) {
+        return event.getEventMessage();
+    }   
+}

cdi/src/main/java/com/baeldung/cdi2observers/observers/ExampleEventObserver.java

@@ -0,0 +1,13 @@
+package com.baeldung.cdi.cdi2observers.observers;
+
+import com.baeldung.cdi.cdi2observers.events.ExampleEvent;
+import com.baeldung.cdi.cdi2observers.services.TextService;
+import javax.annotation.Priority;
+import javax.enterprise.event.Observes;
+
+public class ExampleEventObserver {
+    
+    public String onEvent(@Observes @Priority(1) ExampleEvent event, TextService textService) {
+        return textService.parseText(event.getEventMessage());
+    } 
+}

cdi/src/main/java/com/baeldung/cdi2observers/services/TextService.java

@@ -0,0 +1,8 @@
+package com.baeldung.cdi.cdi2observers.services;
+
+public class TextService {
+
+    public String parseText(String text) {
+        return text.toUpperCase();
+    }
+}

cdi/src/test/java/com/baeldung/test/cdi2observers/tests/TextServiceUnitTest.java

@@ -0,0 +1,14 @@
+package com.baeldung.cdi.cdi2observers.tests;
+
+import com.baeldung.cdi.cdi2observers.services.TextService;
+import static org.assertj.core.api.Assertions.assertThat;
+import org.junit.Test;
+
+public class TextServiceUnitTest {
+
+    @Test
+    public void givenTextServiceInstance_whenCalledparseText_thenCorrect() {
+        TextService textService = new TextService();
+        assertThat(textService.parseText("Baeldung")).isEqualTo("BAELDUNG");
+    }
+}