code: @Nullable
    public String getFirstParamValue (@Nullable final String sName)
    {
      return sName == null ? null : findFirstMapped (aParam -> aParam.hasName (sName), URLParameter::getValue);
    }
docs: Get the value of the first parameter with the provided name
  
  @param sName
  The parameter name to search
  @return <code>null</code> if no such parameter is present.