diff --git a/src/main/java/xyz/zhouxy/plusone/commons/annotation/DefinedIn.java b/src/main/java/xyz/zhouxy/plusone/commons/annotation/DefinedIn.java
deleted file mode 100644
index eb21c73..0000000
--- a/src/main/java/xyz/zhouxy/plusone/commons/annotation/DefinedIn.java
+++ /dev/null
@@ -1,12 +0,0 @@
-package xyz.zhouxy.plusone.commons.annotation;
-
-import java.lang.annotation.ElementType;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
-import java.lang.annotation.Target;
-
-@Target(ElementType.METHOD)
-@Retention(RetentionPolicy.SOURCE)
-public @interface DefinedIn {
-    Class<?>[] value();
-}
diff --git a/src/test/java/xyz/zhouxy/plusone/commons/annotation/ExplicitImplTest.java b/src/test/java/xyz/zhouxy/plusone/commons/annotation/ExplicitImplTest.java
deleted file mode 100644
index ab91be7..0000000
--- a/src/test/java/xyz/zhouxy/plusone/commons/annotation/ExplicitImplTest.java
+++ /dev/null
@@ -1,45 +0,0 @@
-package xyz.zhouxy.plusone.commons.annotation;
-
-import static org.junit.jupiter.api.Assertions.*;
-
-import org.junit.jupiter.api.Test;
-
-class ExplicitImplTest {
-
-    @Test
-    void test() {
-
-    }
-}
-
-interface A {
-
-    void fooA();
-
-    void fooAll();
-}
-
-interface B {
-
-    void fooB();
-
-    void fooAll();
-}
-
-class C implements A, B {
-
-    @DefinedIn(A.class)
-    @Override
-    public void fooA() {
-    }
-
-    @DefinedIn(B.class)
-    @Override
-    public void fooB() {
-    }
-
-    @DefinedIn({ A.class, B.class })
-    @Override
-    public void fooAll() {
-    }
-}