Integer genExprNodeDescRegex(String colRegex, String tabAlias, ASTNode sel,
      List<ExprNodeDesc> exprList, Set<ColumnInfo> excludeCols, RowResolver input,
      RowResolver colSrcRR, Integer pos, RowResolver output, List<String> aliases,
      boolean ensureUniqueCols) throws SemanticException {
    List<Pair<ColumnInfo, RowResolver>> colList = new ArrayList<>();
    Integer i = genColListRegex(colRegex, tabAlias, sel,
        colList, excludeCols, input, colSrcRR, pos, output, aliases, ensureUniqueCols);
    for (Pair<ColumnInfo, RowResolver> p : colList) {
      exprList.add(ExprNodeTypeCheck.toExprNode(p.getLeft(), p.getRight()));
    }
    return i;
  }
create a filter plan. The condition and the inputs are specified.

@param qb
         current query block
@param condn
         The condition to be resolved
@param input
         the input operator
ql/src/java/org/apache/hadoop/hive/ql/parse/SemanticAnalyzer.java