diff --git a/docs/java/basis/why-there-only-value-passing-in-java.md b/docs/java/basis/why-there-only-value-passing-in-java.md
index 42a79280..ceb91b5b 100644
--- a/docs/java/basis/why-there-only-value-passing-in-java.md
+++ b/docs/java/basis/why-there-only-value-passing-in-java.md
@@ -177,7 +177,7 @@ int main()
 {
     int age = 10;
     std::cout << "invoke before: " << age << "\n";
-    incr(age);
+    incr(*age);
     std::cout << "invoke after: " << age << "\n";
 }
 ```