public HttpRequest contentType(final String value,final String charset){
  if (charset != null && charset.length() > 0) {
    final String separator="; " + PARAM_CHARSET + '=';
    return header(HEADER_CONTENT_TYPE,value + separator + charset);
  }
 else   return header(HEADER_CONTENT_TYPE,value);
}

public HttpRequest contentType ( final String value , final String charset ) { if ( charset != null && charset . length ( ) > 0 ) { final String separator = "; " + PARAM_CHARSET + '=' ; return header ( HEADER_CONTENT_TYPE , value + separator + charset ) ; } else return header ( HEADER_CONTENT_TYPE , value ) ; }
set the ' content - type ' request header to the given value and charset
