diff --git a/java/sdk_library.go b/java/sdk_library.go
index 3065d57..daf932e 100644
--- a/java/sdk_library.go
+++ b/java/sdk_library.go
@@ -1206,11 +1206,16 @@
 
 func (module *SdkLibrary) OutputFiles(tag string) (android.Paths, error) {
 	paths, err := module.commonOutputFiles(tag)
-	if paths == nil && err == nil {
-		return module.Library.OutputFiles(tag)
-	} else {
+	if paths != nil || err != nil {
 		return paths, err
 	}
+	if module.requiresRuntimeImplementationLibrary() {
+		return module.Library.OutputFiles(tag)
+	}
+	if tag == "" {
+		return nil, nil
+	}
+	return nil, fmt.Errorf("unsupported module reference tag %q", tag)
 }
 
 func (module *SdkLibrary) GenerateAndroidBuildActions(ctx android.ModuleContext) {