code: public void verifyPasswordAge(ModeledUser user) throws GuacamoleException {
  
          // Retrieve password policy from environment
          PasswordPolicy policy = environment.getPasswordPolicy();
  
          long minimumAge = policy.getMinimumAge();
          long passwordAge = getPasswordAge(user);
  
          // Require that sufficient time has elapsed before allowing the password
          // to be changed
          if (passwordAge < minimumAge)
              throw new PasswordTooYoungException("Password was already recently changed.",
                      minimumAge - passwordAge);
  
      }
docs: Verifies that the given user can change their password without violating
  password aging policy. If changing the user's password would violate the
  aging policy, a GuacamoleException will be thrown.
  
  @param user
  The user whose password is changing.
  
  @throws GuacamoleException
  If the user's password cannot be changed due to the password aging
  policy, or of the password policy cannot be parsed from
  guacamole.properties.