diff --git a/java/base.go b/java/base.go
index b4f800b..1a6584b 100644
--- a/java/base.go
+++ b/java/base.go
@@ -1852,7 +1852,7 @@
 	classes := android.PathForModuleOut(ctx, "javac", jarName).OutputPath
 	TransformJavaToClasses(ctx, classes, idx, srcFiles, srcJars, annoSrcJar, flags, extraJarDeps)
 
-	if ctx.Config().EmitXrefRules() {
+	if ctx.Config().EmitXrefRules() && ctx.Module() == ctx.PrimaryModule() {
 		extractionFile := android.PathForModuleOut(ctx, kzipName)
 		emitXrefRule(ctx, extractionFile, idx, srcFiles, srcJars, flags, extraJarDeps)
 		j.kytheFiles = append(j.kytheFiles, extractionFile)