Add first test

immutables/src/main/java/com/baeldung/immutable/Address.java

@@ -1,5 +1,9 @@
 package com.baeldung.immutable;
 
-public class Address {
+import org.immutables.value.Value;
 
+@Value.Immutable
+public interface Address {
+    String getStreetName();
+    Integer getNumber();
 }

immutables/src/main/java/com/baeldung/immutable/Person.java

@@ -3,6 +3,7 @@ package com.baeldung.immutable;
 import org.immutables.value.Value;
 
 @Value.Immutable
-public class Person {
-    private String name;
+public abstract class Person {
+    abstract String getName();
+    abstract Integer getAge();
 }