public String buildNextPageUrl(final byte[] lastRow) {
    final QueryStringEncoder encoder = buildFirstPageEncoder();
    final String startRow = buildStartParamFrom(lastRow);
    addParam(encoder, SCAN_START_PARAM, startRow);
    return encoder.toString();
  }
Adds {@code value} to {@code encoder} under {@code paramName} when {@code value} is non-null.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/http/MetaBrowser.java