Changes between Version 2 and Version 3 of FDORfc17

Timestamp:

Mar 20, 2008, 2:56:29 PM (16 years ago)

Author:

gregboone

Comment:

--

FDORfc17

@@ -24 +24 @@
 The purpose of this RFC is to determine if there is a need to design and add a Managed API for the FDO Expression Engine.
 
+== Motivation ==
+
+The Unmanaged FDO Expression Engine has a set of unmanaged interfaces but does not have a corresponding managed set of interfaces. The general rule has been that if an unmanaged component of the API is released in the SDK for external use, it should have a corresponding managed API as well.
+
+== Proposed Solution ==
+
+The following shows the proposed additions for the Managed API
+
+=== FDO Expression Engine ===
+
+{{{
+
+public __gc class ExpressionEngine : public NAMESPACE_OSGEO_RUNTIME::Disposable
+{
+public:
+    /// \brief
+    /// Constructs an instance of an ExpressionEngine
+    /// 
+    /// \param reader 
+    /// Input FDO feature reader
+    /// 
+    /// \param classDef
+    /// Input FDO class definition
+    ///
+    /// \param userDefinedFunctions
+    /// Input User defined functions
+    ///
+    ExpressionEngine(OSGEO_FDO_COMMANDS_FEATURE::IReader* reader, 
+                     OSGEO_FDO_SCHEMA::ClassDefinition* classDef, 
+                     OSGEO_FDO_UTILITIES_EXPRESSIONENGINE::FunctionCollection *userDefinedFunctions);
+
+    /// \brief
+    /// Constructs an instance of an ExpressionException.
+    /// 
+    /// \param reader 
+    /// Input reader
+    /// 
+    /// \param classDef
+    /// Input class definition
+    ///
+    /// \param classDef
+    /// Input identifiers
+    ///
+    /// \param userDefinedFunctions
+    /// Input user defined functions
+    ///
+    /// \return
+    /// Returns ExpressionEngine
+    /// 
+    ExpressionEngine(OSGEO_FDO_COMMANDS_FEATURE::IReader* reader, 
+                     OSGEO_FDO_SCHEMA::ClassDefinition* classDef, 
+                     OSGEO_FDO_COMMANDS::IdentifierCollection* identifiers, 
+                     OSGEO_FDO_UTILITIES_EXPRESSIONENGINE::FunctionCollection *userDefinedFunctions);
+
+    /// \brief
+    /// Evaluates an expression
+    /// 
+    /// \param expression 
+    /// Input expression
+    /// 
+    /// \return
+    /// Returns a literal value. This value is valid until the next Evaluate call
+    /// 
+    FdoLiteralValue* Evaluate(OSGEO_FDO_EXPRESSION::Expression *expression);
+
+    /// \brief
+    /// Evaluates a name
+    /// 
+    /// \param name 
+    /// Input identifier
+    /// 
+    /// \return
+    /// Returns a literal value. This value is valid until the next Evaluate call
+    /// 
+    FdoLiteralValue* Evaluate(System::String* name);
+
+    /// \brief
+    /// Evaluates an identifier
+    /// 
+    /// \param identifier
+    /// Input identifier
+    /// 
+    /// \return
+    /// Returns a literal value. This value is valid until the next Evaluate call
+    /// 
+    FdoLiteralValue* Evaluate(OSGEO_FDO_EXPRESSION::Identifier* expr);
+
+
+    /// \brief
+    /// Evaluates an aggregate functions
+    /// 
+    /// \return
+    /// Returns the aggragate results
+    /// 
+    FdoPropertyValueCollection* RunQuery();
+
+    /// \brief
+    /// Checks if passes the filter
+    /// 
+    /// \param filter
+    /// Input filter
+    /// 
+    /// \return
+    /// Returns true id passes the filter, otherwise false
+    /// 
+    bool ProcessFilter(OSGEO_FDO_FILTER::Filter *filter);
+
+    /// \brief
+    /// Returns the default functions plus the user defined functions
+    /// 
+    /// \return
+    /// Returns the functions
+    /// 
+    OSGEO_FDO_CONNECTIONS_CAPABILITIES::FunctionDefinitionCollection *GetAllFunctions();
+
+    /// \brief
+    /// Returns the default functions the expression engine supports
+    /// 
+    /// \return
+    /// Returns the functions
+    /// 
+    static OSGEO_FDO_CONNECTIONS_CAPABILITIES::FunctionDefinitionCollection *GetStandardFunctions();
+
+    /// \brief
+    /// Checks if the filter is valid
+    /// 
+    /// \param cls
+    /// Input class definition
+    /// 
+    /// \param filter
+    /// Input filter
+    /// 
+    /// \param selIds
+    /// Input identifier collection
+    /// 
+    /// \param filterCapabilities
+    /// Input filter capabilities
+    /// 
+    /// \return
+    /// Throws an exception is filter is not valid
+    /// 
+    static System::Void ValidateFilter(OSGEO_FDO_SCHEMA::ClassDefinition *cls, 
+                                       OSGEO_FDO_FILTER::Filter *filter, 
+                                       OSGEO_FDO_COMMANDS::IdentifierCollection *selIds = NULL, 
+                                       OSGEO_FDO_CONNECTIONS_CAPABILITIES::IFilterCapabilities *filterCapabilities = NULL);
+
+    /// \brief
+    /// Optimizes the filter
+    /// 
+    /// \param filter
+    /// Input the filter
+    ///
+    /// \return
+    /// The optimized filter
+    /// 
+    static OSGEO_FDO_FILTER::Filter* OptimizeFilter( OSGEO_FDO_FILTER::Filter *filter );
+
+    /// \brief
+    /// Checks if the function name is a aggregate function
+    /// 
+    /// \param funcDefs
+    /// Input the list of functions
+    ///
+    /// \param name
+    /// Input the function name
+    ///
+    /// \return
+    /// True if the function is an aggregate function otherwise false
+    /// 
+    static bool IsAggregateFunction(OSGEO_FDO_CONNECTIONS_CAPABILITIES::FunctionDefinitionCollection *funcDefs, 
+                                    System::String *name);
+
+    /// \brief
+    /// Returns the type of expression
+    /// 
+    /// \param functions
+    /// Input the list of functions
+    ///
+    /// \param originalClassDef
+    /// Input the class definition
+    ///
+    /// \param propType
+    /// Output the property type
+    ///
+    /// \param dataType
+    /// Output the data type
+    ///
+    /// \return
+    /// Returns nothing
+    /// 
+    static System::Void GetExpressionType(OSGEO_FDO_CONNECTIONS_CAPABILITIES::FunctionDefinitionCollection *functionDefinitions, 
+                                          OSGEO_FDO_SCHEMA::ClassDefinition* originalClassDef, 
+                                          OSGEO_FDO_EXPRESSION::Expression *expr, 
+                                          OSGEO_FDO_SCHEMA::PropertyType &retPropType, 
+                                          OSGEO_FDO_SCHEMA::DataType &retDataType);
+
+    /// \brief
+    /// Returns the type of expression
+    ///
+    /// \param originalClassDef
+    /// Input the class definition
+    ///
+    /// \param propType
+    /// Output the property type
+    ///
+    /// \param dataType
+    /// Output the data type
+    ///
+    /// \return
+    /// Returns nothing
+    /// 
+    static System::Void GetExpressionType(OSGEO_FDO_SCHEMA::ClassDefinition* originalClassDef, 
+                                          OSGEO_FDO_EXPRESSION::Expression *expr, 
+                                          OSGEO_FDO_SCHEMA::PropertyType &retPropType, 
+                                          OSGEO_FDO_SCHEMA::DataType &retDataType);
+
+    /// \brief
+    /// Registers the user-defined functions
+    ///
+    /// \param userDefinedFunctions
+    /// Input the user-defined functions
+    ///
+    /// \return
+    /// Returns nothing
+    /// 
+    static System::Void RegisterFunctions(OSGEO_FDO_UTILITIES_EXPRESSIONENGINE::FunctionCollection *userDefinedFunctions);
+
+};
+
+}}}