diff --git a/v23/naming/jni.go b/v23/naming/jni.go
index 970b9d1..4a93786 100644
--- a/v23/naming/jni.go
+++ b/v23/naming/jni.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build java android
+
 package naming
 
 import (
diff --git a/v23/naming/util.go b/v23/naming/util.go
index 7864d53..c449e4b 100644
--- a/v23/naming/util.go
+++ b/v23/naming/util.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build java android
+
 package naming
 
 import (