connectivity/source/inc/RowFunctionParser.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
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   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
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   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #ifndef INCLUDED_CONNECTIVITY_SOURCE_INC_ROWFUNCTIONPARSER_HXX
  21 #define INCLUDED_CONNECTIVITY_SOURCE_INC_ROWFUNCTIONPARSER_HXX
  22
  23 #include <sal/config.h>
  24 #include "FDatabaseMetaDataResultSet.hxx"
  25 #include <connectivity/dbtoolsdllapi.hxx>
  26 #include <memory>
  27
  28 namespace connectivity
  29 {
  30 enum class ExpressionFunct
  31 {
  32     Equation,
  33     And,
  34     Or
  35 };
  36
  37 #define EXPRESSION_FLAG_SUMANGLE_MODE 1
  38
  39 class OOO_DLLPUBLIC_DBTOOLS SAL_NO_VTABLE ExpressionNode
  40 {
  41 public:
  42     virtual ~ExpressionNode() {}
  43
  44     /** Operator to calculate function value.
  45
  46         This method calculates the function value.
  47     */
  48     virtual ORowSetValueDecoratorRef
  49     evaluate(const ODatabaseMetaDataResultSet::ORow& _aRow) const = 0;
  50
  51     virtual void fill(const ODatabaseMetaDataResultSet::ORow& _aRow) const = 0;
  52 };
  53
  54 /** This exception is thrown, when the arithmetic expression
  55     parser failed to parse a string.
  56     */
  57 struct OOO_DLLPUBLIC_DBTOOLS ParseError
  58 {
  59     ParseError(const char*) {}
  60 };
  61
  62 class FunctionParser
  63 {
  64 public:
  65     /** Parse a string
  66
  67         The following grammar is accepted by this method:
  68         <code>
  69
  70         number_digit = '0'|'1'|'2'|'3'|'4'|'5'|'6'|'7'|'8'|'9'
  71
  72         number = number number_digit | number_digit
  73
  74         equal_function = '='
  75         ternary_function = 'if'
  76
  77         string_reference = 'a-z,A-Z,0-9' ' '
  78         modifier_reference = '$' '0-9' ' '
  79
  80         basic_expression =
  81             number |
  82             string_reference |
  83             additive_expression equal_function additive_expression |
  84             unary_function '(' number_digit ')'
  85             ternary_function '(' additive_expression ',' additive_expression ',
  86                                ' additive_expression ')' | '(' additive_expression ')'
  87
  88         </code>
  89
  90         @param rFunction
  91         The string to parse
  92
  93         @throws ParseError if an invalid expression is given.
  94
  95         @return the generated function object.
  96        */
  97
  98     static std::shared_ptr<ExpressionNode> const& parseFunction(const OUString& _sFunction);
  99
 100 private:
 101     // disabled constructor/destructor, since this is
 102     // supposed to be a singleton
 103     FunctionParser() = delete;
 104     FunctionParser(const FunctionParser&) = delete;
 105     FunctionParser& operator=(const FunctionParser&) = delete;
 106 };
 107
 108 } // namespace connectivity
 109
 110 #endif // INCLUDED_CONNECTIVITY_SOURCE_INC_ROWFUNCTIONPARSER_HXX
 111
 112 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */