diff --git a/java-strings/src/main/java/com/baeldung/enums/Pizza.java b/core-java/src/main/java/com/baeldung/enums/Pizza.java
similarity index 100%
rename from java-strings/src/main/java/com/baeldung/enums/Pizza.java
rename to core-java/src/main/java/com/baeldung/enums/Pizza.java
diff --git a/java-strings/src/main/java/com/baeldung/enums/PizzaDeliveryStrategy.java b/core-java/src/main/java/com/baeldung/enums/PizzaDeliveryStrategy.java
similarity index 100%
rename from java-strings/src/main/java/com/baeldung/enums/PizzaDeliveryStrategy.java
rename to core-java/src/main/java/com/baeldung/enums/PizzaDeliveryStrategy.java
diff --git a/java-strings/src/main/java/com/baeldung/enums/PizzaDeliverySystemConfiguration.java b/core-java/src/main/java/com/baeldung/enums/PizzaDeliverySystemConfiguration.java
similarity index 100%
rename from java-strings/src/main/java/com/baeldung/enums/PizzaDeliverySystemConfiguration.java
rename to core-java/src/main/java/com/baeldung/enums/PizzaDeliverySystemConfiguration.java
diff --git a/java-strings/src/main/java/com/baeldung/enums/README.md b/core-java/src/main/java/com/baeldung/enums/README.md
similarity index 100%
rename from java-strings/src/main/java/com/baeldung/enums/README.md
rename to core-java/src/main/java/com/baeldung/enums/README.md
diff --git a/core-java/src/test/java/com/baeldung/enums/PizzaUnitTest.java b/core-java/src/test/java/com/baeldung/enums/PizzaUnitTest.java
new file mode 100644
index 0000000000..35aa07821c
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/enums/PizzaUnitTest.java
@@ -0,0 +1,100 @@
+package com.baeldung.enums;
+
+import com.baeldung.enums.Pizza.PizzaStatusEnum;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.EnumMap;
+import java.util.List;
+
+import static junit.framework.TestCase.assertTrue;
+
+public class PizzaUnitTest {
+
+    @Test
+    public void givenPizaOrder_whenReady_thenDeliverable() {
+        Pizza testPz = new Pizza();
+        testPz.setStatus(Pizza.PizzaStatusEnum.READY);
+        assertTrue(testPz.isDeliverable());
+    }
+
+    @Test
+    public void givenPizaOrders_whenRetrievingUnDeliveredPzs_thenCorrectlyRetrieved() {
+        List<Pizza> pzList = new ArrayList<>();
+        Pizza pz1 = new Pizza();
+        pz1.setStatus(Pizza.PizzaStatusEnum.DELIVERED);
+
+        Pizza pz2 = new Pizza();
+        pz2.setStatus(Pizza.PizzaStatusEnum.ORDERED);
+
+        Pizza pz3 = new Pizza();
+        pz3.setStatus(Pizza.PizzaStatusEnum.ORDERED);
+
+        Pizza pz4 = new Pizza();
+        pz4.setStatus(Pizza.PizzaStatusEnum.READY);
+
+        pzList.add(pz1);
+        pzList.add(pz2);
+        pzList.add(pz3);
+        pzList.add(pz4);
+
+        List<Pizza> undeliveredPzs = Pizza.getAllUndeliveredPizzas(pzList);
+        assertTrue(undeliveredPzs.size() == 3);
+    }
+
+    @Test
+    public void givenPizaOrders_whenGroupByStatusCalled_thenCorrectlyGrouped() {
+
+        List<Pizza> pzList = new ArrayList<>();
+        Pizza pz1 = new Pizza();
+        pz1.setStatus(Pizza.PizzaStatusEnum.DELIVERED);
+
+        Pizza pz2 = new Pizza();
+        pz2.setStatus(Pizza.PizzaStatusEnum.ORDERED);
+
+        Pizza pz3 = new Pizza();
+        pz3.setStatus(Pizza.PizzaStatusEnum.ORDERED);
+
+        Pizza pz4 = new Pizza();
+        pz4.setStatus(Pizza.PizzaStatusEnum.READY);
+
+        pzList.add(pz1);
+        pzList.add(pz2);
+        pzList.add(pz3);
+        pzList.add(pz4);
+
+        EnumMap<Pizza.PizzaStatusEnum, List<Pizza>> map = Pizza.groupPizzaByStatus(pzList);
+        assertTrue(map.get(Pizza.PizzaStatusEnum.DELIVERED).size() == 1);
+        assertTrue(map.get(Pizza.PizzaStatusEnum.ORDERED).size() == 2);
+        assertTrue(map.get(Pizza.PizzaStatusEnum.READY).size() == 1);
+    }
+
+    @Test
+    public void whenDelivered_thenPizzaGetsDeliveredAndStatusChanges() {
+        Pizza pz = new Pizza();
+        pz.setStatus(Pizza.PizzaStatusEnum.READY);
+        pz.deliver();
+        assertTrue(pz.getStatus() == Pizza.PizzaStatusEnum.DELIVERED);
+    }
+    
+    @Test
+    public void whenConvertedIntoEnum_thenGetsConvertedCorrectly() {
+        String pizzaEnumValue = "READY";
+        PizzaStatusEnum pizzaStatusEnum = PizzaStatusEnum.valueOf(pizzaEnumValue);
+        assertTrue(pizzaStatusEnum == PizzaStatusEnum.READY);
+    }
+    
+    @Test(expected = IllegalArgumentException.class)
+    public void whenConvertedIntoEnum_thenThrowsException() {
+        String pizzaEnumValue = "rEAdY";
+        PizzaStatusEnum pizzaStatusEnum = PizzaStatusEnum.valueOf(pizzaEnumValue);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void givenInvalidEnumValueContentWiseAsString_whenConvertedIntoEnum_thenThrowsException() {
+        String pizzaEnumValue = "invalid";
+        PizzaStatusEnum pizzaStatusEnum = PizzaStatusEnum.valueOf(pizzaEnumValue);
+    }
+    
+
+}
diff --git a/java-strings/src/test/java/org/baeldung/java/enums/PizzaUnitTest.java b/core-java/src/test/java/org/baeldung/java/enums/PizzaUnitTest.java
similarity index 100%
rename from java-strings/src/test/java/org/baeldung/java/enums/PizzaUnitTest.java
rename to core-java/src/test/java/org/baeldung/java/enums/PizzaUnitTest.java
diff --git a/java-strings/src/main/java/com/baeldung/enums/PizzaStatusEnum.java b/java-strings/src/main/java/com/baeldung/enums/PizzaStatusEnum.java
new file mode 100644
index 0000000000..a84829c38d
--- /dev/null
+++ b/java-strings/src/main/java/com/baeldung/enums/PizzaStatusEnum.java
@@ -0,0 +1,44 @@
+package com.baeldung.enums;
+
+public enum PizzaStatusEnum {
+    ORDERED(5) {
+        @Override
+        public boolean isOrdered() {
+            return true;
+        }
+    },
+    READY(2) {
+        @Override
+        public boolean isReady() {
+            return true;
+        }
+    },
+    DELIVERED(0) {
+        @Override
+        public boolean isDelivered() {
+            return true;
+        }
+    };
+
+    private int timeToDelivery;
+
+    public boolean isOrdered() {
+        return false;
+    }
+
+    public boolean isReady() {
+        return false;
+    }
+
+    public boolean isDelivered() {
+        return false;
+    }
+
+    public int getTimeToDelivery() {
+        return timeToDelivery;
+    }
+
+    PizzaStatusEnum(int timeToDelivery) {
+        this.timeToDelivery = timeToDelivery;
+    }
+}
diff --git a/java-strings/src/test/java/com/baeldung/enums/PizzaUnitTest.java b/java-strings/src/test/java/com/baeldung/enums/PizzaUnitTest.java
index 35aa07821c..3e52a89bad 100644
--- a/java-strings/src/test/java/com/baeldung/enums/PizzaUnitTest.java
+++ b/java-strings/src/test/java/com/baeldung/enums/PizzaUnitTest.java
@@ -1,81 +1,10 @@
 package com.baeldung.enums;
 
-import com.baeldung.enums.Pizza.PizzaStatusEnum;
-import org.junit.Test;
-
-import java.util.ArrayList;
-import java.util.EnumMap;
-import java.util.List;
-
 import static junit.framework.TestCase.assertTrue;
 
+import org.junit.Test;
+
 public class PizzaUnitTest {
-
-    @Test
-    public void givenPizaOrder_whenReady_thenDeliverable() {
-        Pizza testPz = new Pizza();
-        testPz.setStatus(Pizza.PizzaStatusEnum.READY);
-        assertTrue(testPz.isDeliverable());
-    }
-
-    @Test
-    public void givenPizaOrders_whenRetrievingUnDeliveredPzs_thenCorrectlyRetrieved() {
-        List<Pizza> pzList = new ArrayList<>();
-        Pizza pz1 = new Pizza();
-        pz1.setStatus(Pizza.PizzaStatusEnum.DELIVERED);
-
-        Pizza pz2 = new Pizza();
-        pz2.setStatus(Pizza.PizzaStatusEnum.ORDERED);
-
-        Pizza pz3 = new Pizza();
-        pz3.setStatus(Pizza.PizzaStatusEnum.ORDERED);
-
-        Pizza pz4 = new Pizza();
-        pz4.setStatus(Pizza.PizzaStatusEnum.READY);
-
-        pzList.add(pz1);
-        pzList.add(pz2);
-        pzList.add(pz3);
-        pzList.add(pz4);
-
-        List<Pizza> undeliveredPzs = Pizza.getAllUndeliveredPizzas(pzList);
-        assertTrue(undeliveredPzs.size() == 3);
-    }
-
-    @Test
-    public void givenPizaOrders_whenGroupByStatusCalled_thenCorrectlyGrouped() {
-
-        List<Pizza> pzList = new ArrayList<>();
-        Pizza pz1 = new Pizza();
-        pz1.setStatus(Pizza.PizzaStatusEnum.DELIVERED);
-
-        Pizza pz2 = new Pizza();
-        pz2.setStatus(Pizza.PizzaStatusEnum.ORDERED);
-
-        Pizza pz3 = new Pizza();
-        pz3.setStatus(Pizza.PizzaStatusEnum.ORDERED);
-
-        Pizza pz4 = new Pizza();
-        pz4.setStatus(Pizza.PizzaStatusEnum.READY);
-
-        pzList.add(pz1);
-        pzList.add(pz2);
-        pzList.add(pz3);
-        pzList.add(pz4);
-
-        EnumMap<Pizza.PizzaStatusEnum, List<Pizza>> map = Pizza.groupPizzaByStatus(pzList);
-        assertTrue(map.get(Pizza.PizzaStatusEnum.DELIVERED).size() == 1);
-        assertTrue(map.get(Pizza.PizzaStatusEnum.ORDERED).size() == 2);
-        assertTrue(map.get(Pizza.PizzaStatusEnum.READY).size() == 1);
-    }
-
-    @Test
-    public void whenDelivered_thenPizzaGetsDeliveredAndStatusChanges() {
-        Pizza pz = new Pizza();
-        pz.setStatus(Pizza.PizzaStatusEnum.READY);
-        pz.deliver();
-        assertTrue(pz.getStatus() == Pizza.PizzaStatusEnum.DELIVERED);
-    }
     
     @Test
     public void whenConvertedIntoEnum_thenGetsConvertedCorrectly() {
@@ -95,6 +24,4 @@ public class PizzaUnitTest {
         String pizzaEnumValue = "invalid";
         PizzaStatusEnum pizzaStatusEnum = PizzaStatusEnum.valueOf(pizzaEnumValue);
     }
-    
-
-}
+}
\ No newline at end of file