@Override
    public void validateEndState(ScanContext ctx) throws InvalidQueryException {
      if (ctx.getBracketScore() > 0) {
        throw new InvalidQueryException("Missing closing bracket for function: " + ctx.getTokenList());
      }
    }
Complex Value Operand token handler.
Supports values that span multiple tokens.
ambari-server/src/main/java/org/apache/ambari/server/api/predicate/QueryLexer.java