docs: public ClassGraph whitelistPackagesNonRecursive(final String... packageNames) {
          enableClassInfo();
          for (final String packageName : packageNames) {
              final String packageNameNormalized = WhiteBlackList.normalizePackageOrClassName(packageName);
              if (packageNameNormalized.contains("*")) {
                  throw new IllegalArgumentException("Cannot use a glob wildcard here: " + packageNameNormalized);
              }
              // Whitelist package, but not sub-packages
              scanSpec.packageWhiteBlackList.addToWhitelist(packageNameNormalized);
              scanSpec.pathWhiteBlackList
                      .addToWhitelist(WhiteBlackList.packageNameToPath(packageNameNormalized) + "/");
              if (packageNameNormalized.isEmpty()) {
                  scanSpec.pathWhiteBlackList.addToWhitelist("");
              }
          }
          return this;
      }