新增 DefinedIn 注解。

src/main/java/xyz/zhouxy/plusone/commons/annotation/DefinedIn.java

@@ -0,0 +1,12 @@
+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();
+}

src/test/java/xyz/zhouxy/plusone/commons/annotation/ExplicitImplTest.java

@@ -0,0 +1,45 @@
+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() {
+    }
+}