diff --git a/core-java-modules/core-java-lang-oop-generics/src/main/java/com/baeldung/holder/Holder.java b/core-java-modules/core-java-lang-oop-generics/src/main/java/com/baeldung/holder/Holder.java
deleted file mode 100644
index da066ee5c6..0000000000
--- a/core-java-modules/core-java-lang-oop-generics/src/main/java/com/baeldung/holder/Holder.java
+++ /dev/null
@@ -1,9 +0,0 @@
-package com.baeldung.holder;
-
-public class Holder<T> {
-    public T value;
-
-    public Holder(T value) {
-        this.value = value;
-    }
-}
diff --git a/core-java-modules/core-java-lang-oop-generics/src/main/java/com/baeldung/holder/SupplierService.java b/core-java-modules/core-java-lang-oop-generics/src/main/java/com/baeldung/holder/SupplierService.java
deleted file mode 100644
index 66889f99bf..0000000000
--- a/core-java-modules/core-java-lang-oop-generics/src/main/java/com/baeldung/holder/SupplierService.java
+++ /dev/null
@@ -1,11 +0,0 @@
-package com.baeldung.holder;
-
-public class SupplierService {
-    public void getSupplierByZipCode(String zip, Holder<Boolean> resultHolder) {
-        if (zip.startsWith("9")) {
-            resultHolder.value = true;
-        } else {
-            resultHolder.value = false;
-        }
-    }
-}
diff --git a/core-java-modules/core-java-lang-oop-generics/src/test/java/com/baeldung/holder/SupplierServiceUnitTest.java b/core-java-modules/core-java-lang-oop-generics/src/test/java/com/baeldung/holder/SupplierServiceUnitTest.java
deleted file mode 100644
index e1446fc229..0000000000
--- a/core-java-modules/core-java-lang-oop-generics/src/test/java/com/baeldung/holder/SupplierServiceUnitTest.java
+++ /dev/null
@@ -1,31 +0,0 @@
-package com.baeldung.holder;
-
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
-import org.junit.jupiter.api.Test;
-
-public class SupplierServiceUnitTest {
-
-    @Test
-    public void givenValidZipCode_whenGetSupplierByZipCode_thenTrue() {
-        SupplierService service = new SupplierService();
-        Holder<Boolean> resultHolder = new Holder<>(false);
-        String zipCode = "98682";
-
-        service.getSupplierByZipCode(zipCode, resultHolder);
-
-        assertTrue(resultHolder.value);
-    }
-
-    @Test
-    public void givenInvalidZipCode_whenGetSupplierByZipCode_thenFalse() {
-        SupplierService service = new SupplierService();
-        Holder<Boolean> resultHolder = new Holder<>(true);
-        String zipCode = "12345";
-
-        service.getSupplierByZipCode(zipCode, resultHolder);
-
-        assertFalse(resultHolder.value);
-    }
-}