code: String getMatchingJavaEncoding(String javaEncoding) {
          if (javaEncoding != null && this.javaEncodingsUc.contains(javaEncoding.toUpperCase(Locale.ENGLISH))) {
              return javaEncoding;
          }
          return this.javaEncodingsUc.get(0);
      }
docs: If javaEncoding parameter value is one of available java encodings for this charset
  then returns javaEncoding value as is. Otherwise returns first available java encoding name.
  
  @param javaEncoding
  @throws SQLException