How to use

hasInvalidChar

method

in

io.spring.initializr.metadata.InitializrConfiguration

/**
 * Clean the specified package name if necessary. If the package name cannot be
 * transformed to a valid package name, the {@code defaultPackageName} is used
 * instead.
 * <p>
 * The package name cannot be cleaned if the specified {@code packageName} is
 * {@code null} or if it contains an invalid character for a class identifier.
 * @param packageName the package name
 * @param defaultPackageName the default package name
 * @return the cleaned package name
 * @see Env#getInvalidPackageNames()
 */
public String cleanPackageName(String packageName, String defaultPackageName) {
  if (!StringUtils.hasText(packageName)) {
    return defaultPackageName;
  }
  String candidate = cleanPackageName(packageName);
  if (hasInvalidChar(candidate.replace(".", ""))
      || this.env.invalidPackageNames.contains(candidate)) {
    return defaultPackageName;
  }
  else {
    return candidate;
  }
}

if (hasInvalidChar(candidate)
    || this.env.invalidApplicationNames.contains(candidate)) {
  return this.env.fallbackApplicationName;