code: public Headers getHttpHeaders()
      {
          Headers headers = new Headers();
  
          if ( byteRange != null ) {
              StringBuilder rangeBuilder = new StringBuilder( "bytes=" );
  
              long start;
              if ( byteRange.offset >= 0 ) {
                  rangeBuilder.append( byteRange.offset );
                  start = byteRange.offset;
              } else {
                  start = 1;
              }
              rangeBuilder.append( "-" );
              if ( byteRange.length > 0 ) {
                  rangeBuilder.append( start + byteRange.length - 1 );
              }
  
              Header rangeHeader = new BasicHeader( "Range", rangeBuilder.toString() );
              headers.addHeader( rangeHeader );
          }
          return headers;
      }
docs: Get the HTTP headers to be used for download request.
  
  Default implementation only handles Range header.
  
  @return The headers