From a288f8db7e6187b047baba472d71b44edfa42bb1 Mon Sep 17 00:00:00 2001
From: Azhwani <13301425+azhwani@users.noreply.github.com>
Date: Mon, 12 Dec 2022 08:53:16 +0100
Subject: [PATCH] BAEL-5844: Convert Anonymous Class into Lambda in Java
 (#13088)

---
 .../anonymousclass/EmailSenderService.java    | 10 ++++++
 .../com/baeldung/anonymousclass/Sender.java   |  7 ++++
 .../anonymousclass/SenderService.java         |  7 ++++
 .../anonymousclass/SmsSenderService.java      | 10 ++++++
 ...AnonymousClassToLambdaIntegrationTest.java | 34 +++++++++++++++++++
 5 files changed, 68 insertions(+)
 create mode 100644 core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/EmailSenderService.java
 create mode 100644 core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/Sender.java
 create mode 100644 core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/SenderService.java
 create mode 100644 core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/SmsSenderService.java
 create mode 100644 core-java-modules/core-java-lambdas/src/test/java/com/baeldung/anonymousclass/AnonymousClassToLambdaIntegrationTest.java

diff --git a/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/EmailSenderService.java b/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/EmailSenderService.java
new file mode 100644
index 0000000000..f0c41b1cc9
--- /dev/null
+++ b/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/EmailSenderService.java
@@ -0,0 +1,10 @@
+package com.baeldung.anonymousclass;
+
+public class EmailSenderService implements SenderService {
+
+    @Override
+    public String callSender(Sender sender) {
+        return sender.send("Email Notification");
+    }
+
+}
diff --git a/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/Sender.java b/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/Sender.java
new file mode 100644
index 0000000000..9e59960c14
--- /dev/null
+++ b/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/Sender.java
@@ -0,0 +1,7 @@
+package com.baeldung.anonymousclass;
+
+public interface Sender {
+
+    String send(final String message);
+
+}
diff --git a/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/SenderService.java b/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/SenderService.java
new file mode 100644
index 0000000000..cbb0977f89
--- /dev/null
+++ b/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/SenderService.java
@@ -0,0 +1,7 @@
+package com.baeldung.anonymousclass;
+
+public interface SenderService {
+
+    String callSender(Sender sender);
+
+}
diff --git a/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/SmsSenderService.java b/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/SmsSenderService.java
new file mode 100644
index 0000000000..9c84664ec4
--- /dev/null
+++ b/core-java-modules/core-java-lambdas/src/main/java/com/baeldung/anonymousclass/SmsSenderService.java
@@ -0,0 +1,10 @@
+package com.baeldung.anonymousclass;
+
+public class SmsSenderService implements SenderService {
+
+    @Override
+    public String callSender(Sender sender) {
+        return sender.send("SMS Notification");
+    }
+
+}
diff --git a/core-java-modules/core-java-lambdas/src/test/java/com/baeldung/anonymousclass/AnonymousClassToLambdaIntegrationTest.java b/core-java-modules/core-java-lambdas/src/test/java/com/baeldung/anonymousclass/AnonymousClassToLambdaIntegrationTest.java
new file mode 100644
index 0000000000..b329e003f4
--- /dev/null
+++ b/core-java-modules/core-java-lambdas/src/test/java/com/baeldung/anonymousclass/AnonymousClassToLambdaIntegrationTest.java
@@ -0,0 +1,34 @@
+package com.baeldung.anonymousclass;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+public class AnonymousClassToLambdaIntegrationTest {
+
+    @Test
+    public void whenPassingAnonymousClass_thenSuccess() {
+        final SenderService emailSenderService = new EmailSenderService();
+
+        final String emailNotif = emailSenderService.callSender(new Sender() {
+            @Override
+            public String send(String message) {
+                return message;
+            }
+        });
+
+        assertEquals(emailNotif, "Email Notification");
+    }
+
+    @Test
+    public void whenPassingLambdaExpression_thenSuccess() {
+        final SenderService smsSenderService = new SmsSenderService();
+
+        final String smsNotif = smsSenderService.callSender((String message) -> {
+            return message;
+        });
+
+        assertEquals(smsNotif, "SMS Notification");
+    }
+
+}