diff --git a/java/dexpreopt_bootjars.go b/java/dexpreopt_bootjars.go
index 90457d0..ed61d4b 100644
--- a/java/dexpreopt_bootjars.go
+++ b/java/dexpreopt_bootjars.go
@@ -619,10 +619,10 @@
 		// Collect `permitted_packages` for updatable boot jars.
 		var updatablePackages []string
 		ctx.VisitAllModules(func(module android.Module) {
-			if j, ok := module.(*Library); ok {
+			if j, ok := module.(PermittedPackagesForUpdatableBootJars); ok {
 				name := ctx.ModuleName(module)
 				if i := android.IndexList(name, updatableModules); i != -1 {
-					pp := j.properties.Permitted_packages
+					pp := j.PermittedPackagesForUpdatableBootJars()
 					if len(pp) > 0 {
 						updatablePackages = append(updatablePackages, pp...)
 					} else {
diff --git a/java/java.go b/java/java.go
index 162141d..76bfa86 100644
--- a/java/java.go
+++ b/java/java.go
@@ -1840,6 +1840,17 @@
 	InstallMixin func(ctx android.ModuleContext, installPath android.Path) (extraInstallDeps android.Paths)
 }
 
+// Provides access to the list of permitted packages from updatable boot jars.
+type PermittedPackagesForUpdatableBootJars interface {
+	PermittedPackagesForUpdatableBootJars() []string
+}
+
+var _ PermittedPackagesForUpdatableBootJars = (*Library)(nil)
+
+func (j *Library) PermittedPackagesForUpdatableBootJars() []string {
+	return j.properties.Permitted_packages
+}
+
 func shouldUncompressDex(ctx android.ModuleContext, dexpreopter *dexpreopter) bool {
 	// Store uncompressed (and aligned) any dex files from jars in APEXes.
 	if am, ok := ctx.Module().(android.ApexModule); ok && !am.IsForPlatform() {