public static boolean isGreenPackage(PackageInfo packageInfo) {
        return (packageInfo.receivers == null || packageInfo.receivers.length == 0)
                && (packageInfo.services == null || packageInfo.services.length == 0)
                && (packageInfo.activities == null || packageInfo.activities.length == 0);
    }
Those that has not service and broadcast and no activity.
android/android_framework/base/src/main/java/github/tornaco/android/thanos/core/pm/ComponentUtil.java