diff --git a/cglib/src/main/java/com/baeldung/cglib/mixin/Class1.java b/cglib/src/main/java/com/baeldung/cglib/mixin/Class1.java
new file mode 100644
index 0000000000..2921cda8a6
--- /dev/null
+++ b/cglib/src/main/java/com/baeldung/cglib/mixin/Class1.java
@@ -0,0 +1,8 @@
+package com.baeldung.cglib.mixin;
+
+public class Class1 implements Interface1 {
+  @Override
+  public String first() {
+    return "first";
+  }
+}
\ No newline at end of file
diff --git a/cglib/src/main/java/com/baeldung/cglib/mixin/Class2.java b/cglib/src/main/java/com/baeldung/cglib/mixin/Class2.java
new file mode 100644
index 0000000000..0098c9debd
--- /dev/null
+++ b/cglib/src/main/java/com/baeldung/cglib/mixin/Class2.java
@@ -0,0 +1,8 @@
+package com.baeldung.cglib.mixin;
+
+public class Class2 implements Interface2 {
+  @Override
+  public String second() {
+    return "second";
+  }
+}
\ No newline at end of file
diff --git a/cglib/src/main/java/com/baeldung/cglib/mixin/Interface1.java b/cglib/src/main/java/com/baeldung/cglib/mixin/Interface1.java
new file mode 100644
index 0000000000..5aab155c1d
--- /dev/null
+++ b/cglib/src/main/java/com/baeldung/cglib/mixin/Interface1.java
@@ -0,0 +1,5 @@
+package com.baeldung.cglib.mixin;
+
+public interface Interface1 {
+  String first();
+}
\ No newline at end of file
diff --git a/cglib/src/main/java/com/baeldung/cglib/mixin/Interface2.java b/cglib/src/main/java/com/baeldung/cglib/mixin/Interface2.java
new file mode 100644
index 0000000000..7fd2e78608
--- /dev/null
+++ b/cglib/src/main/java/com/baeldung/cglib/mixin/Interface2.java
@@ -0,0 +1,5 @@
+package com.baeldung.cglib.mixin;
+
+public interface Interface2 {
+  String second();
+}
\ No newline at end of file
diff --git a/cglib/src/main/java/com/baeldung/cglib/mixin/MixinInterface.java b/cglib/src/main/java/com/baeldung/cglib/mixin/MixinInterface.java
new file mode 100644
index 0000000000..e7ed362a25
--- /dev/null
+++ b/cglib/src/main/java/com/baeldung/cglib/mixin/MixinInterface.java
@@ -0,0 +1,4 @@
+package com.baeldung.cglib.mixin;
+
+public interface MixinInterface extends Interface1, Interface2 {
+}
\ No newline at end of file
diff --git a/cglib/src/main/java/com/baeldung/cglib/proxy/PersonService.java b/cglib/src/main/java/com/baeldung/cglib/proxy/PersonService.java
new file mode 100644
index 0000000000..9085e6c49a
--- /dev/null
+++ b/cglib/src/main/java/com/baeldung/cglib/proxy/PersonService.java
@@ -0,0 +1,11 @@
+package com.baeldung.cglib.proxy;
+
+public class PersonService {
+    public String sayHello(String name) {
+        return "Hello " + name;
+    }
+
+    public Integer lengthOfName(String name) {
+        return name.length();
+    }
+}
\ No newline at end of file
diff --git a/cglib/src/main/java/com/baeldung/cglib/proxy/SampleClass.java b/cglib/src/main/java/com/baeldung/cglib/proxy/SampleClass.java
deleted file mode 100644
index 3e0d098dd1..0000000000
--- a/cglib/src/main/java/com/baeldung/cglib/proxy/SampleClass.java
+++ /dev/null
@@ -1,7 +0,0 @@
-package com.baeldung.cglib.proxy;
-
-public class SampleClass {
-    public String test(String input) {
-        return "Hello world!";
-    }
-}
\ No newline at end of file
diff --git a/cglib/src/test/java/com/baeldung/cglib/proxy/BeanGeneratorTest.java b/cglib/src/test/java/com/baeldung/cglib/proxy/BeanGeneratorTest.java
new file mode 100644
index 0000000000..4b401ae690
--- /dev/null
+++ b/cglib/src/test/java/com/baeldung/cglib/proxy/BeanGeneratorTest.java
@@ -0,0 +1,28 @@
+package com.baeldung.cglib.proxy;
+
+
+import net.sf.cglib.beans.BeanGenerator;
+import org.junit.Test;
+
+import java.lang.reflect.Method;
+
+import static junit.framework.TestCase.assertEquals;
+
+public class BeanGeneratorTest {
+
+    @Test
+    public void testBeanGenerator() throws Exception {
+        //given
+        BeanGenerator beanGenerator = new BeanGenerator();
+
+        //when
+        beanGenerator.addProperty("value", String.class);
+        Object myBean = beanGenerator.create();
+        Method setter = myBean.getClass().getMethod("setValue", String.class);
+        setter.invoke(myBean, "some string value set by a cglib");
+
+        //then
+        Method getter = myBean.getClass().getMethod("getValue");
+        assertEquals("some string value set by a cglib", getter.invoke(myBean));
+    }
+}
diff --git a/cglib/src/test/java/com/baeldung/cglib/proxy/MixinTest.java b/cglib/src/test/java/com/baeldung/cglib/proxy/MixinTest.java
new file mode 100644
index 0000000000..31e7b2204f
--- /dev/null
+++ b/cglib/src/test/java/com/baeldung/cglib/proxy/MixinTest.java
@@ -0,0 +1,24 @@
+package com.baeldung.cglib.proxy;
+
+import com.baeldung.cglib.mixin.*;
+import net.sf.cglib.proxy.Mixin;
+import org.junit.Test;
+
+import static junit.framework.TestCase.assertEquals;
+
+public class MixinTest {
+
+    @Test
+    public void testMixin() throws Exception {
+        //when
+        Mixin mixin = Mixin.create(
+                new Class[]{Interface1.class, Interface2.class, MixinInterface.class},
+                new Object[]{new Class1(), new Class2()}
+        );
+        MixinInterface mixinDelegate = (MixinInterface) mixin;
+
+        //then
+        assertEquals("first", mixinDelegate.first());
+        assertEquals("second", mixinDelegate.second());
+    }
+}
diff --git a/cglib/src/test/java/com/baeldung/cglib/proxy/PersonServiceProxyTest.java b/cglib/src/test/java/com/baeldung/cglib/proxy/PersonServiceProxyTest.java
new file mode 100644
index 0000000000..2ae6392a05
--- /dev/null
+++ b/cglib/src/test/java/com/baeldung/cglib/proxy/PersonServiceProxyTest.java
@@ -0,0 +1,61 @@
+package com.baeldung.cglib.proxy;
+
+import net.sf.cglib.proxy.Enhancer;
+import net.sf.cglib.proxy.FixedValue;
+import net.sf.cglib.proxy.MethodInterceptor;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class PersonServiceProxyTest {
+    @Test
+    public void testService() {
+        //given
+        PersonService personService = new PersonService();
+
+        //when
+        String res = personService.sayHello("Tom");
+
+        //then
+        assertEquals(res, "Hello Tom");
+    }
+
+    @Test
+    public void testFixedValue() throws Exception {
+        //given
+        Enhancer enhancer = new Enhancer();
+        enhancer.setSuperclass(PersonService.class);
+        enhancer.setCallback((FixedValue) () -> "Hello cglib!");
+        PersonService proxy = (PersonService) enhancer.create();
+
+        //when
+        String res = proxy.sayHello(null);
+
+        //then
+        assertEquals("Hello cglib!", res);
+    }
+
+    @Test
+    public void testMethodInterceptor() throws Exception {
+        //given
+        Enhancer enhancer = new Enhancer();
+        enhancer.setSuperclass(PersonService.class);
+        enhancer.setCallback((MethodInterceptor) (obj, method, args, proxy) -> {
+            if (method.getDeclaringClass() != Object.class && method.getReturnType() == String.class) {
+                return "Hello cglib!";
+            } else {
+                return proxy.invokeSuper(obj, args);
+            }
+        });
+
+        //when
+        PersonService proxy = (PersonService) enhancer.create();
+
+        //then
+        assertEquals("Hello cglib!", proxy.sayHello(null));
+
+        int lengthOfName = proxy.lengthOfName("Mary");
+        assertEquals(4, lengthOfName);
+    }
+
+}
\ No newline at end of file
diff --git a/cglib/src/test/java/com/baeldung/cglib/proxy/SampleClassTest.java b/cglib/src/test/java/com/baeldung/cglib/proxy/SampleClassTest.java
deleted file mode 100644
index 15037b3f1c..0000000000
--- a/cglib/src/test/java/com/baeldung/cglib/proxy/SampleClassTest.java
+++ /dev/null
@@ -1,20 +0,0 @@
-package com.baeldung.cglib.proxy;
-
-import net.sf.cglib.proxy.Enhancer;
-import net.sf.cglib.proxy.FixedValue;
-import org.junit.Test;
-
-import static org.junit.Assert.assertEquals;
-
-public class SampleClassTest {
-    @Test
-    public void testFixedValue() throws Exception {
-        Enhancer enhancer = new Enhancer();
-        enhancer.setSuperclass(SampleClass.class);
-        enhancer.setCallback((FixedValue) () -> "Hello cglib!");
-        SampleClass proxy = (SampleClass) enhancer.create();
-        assertEquals("Hello cglib!", proxy.test(null));
-
-    }
-
-}
\ No newline at end of file