code: public static String validateConstraintName(@Nullable String constraintName) {
      requireNonNull(constraintName, "Constraint name cannot be null");
      checkDbIdentifier(constraintName, "Constraint name", CONSTRAINT_NAME_MAX_SIZE);
      return constraintName;
    }
docs: Ensure {@code constraintName} is a valid name for a constraint.
  @throws NullPointerException if {@code constraintName} is {@code null}
  @throws IllegalArgumentException if {@code constraintName} is not valid
  @return the same {@code constraintName}
  @see #checkDbIdentifier(String, String, int)