epoc32/include/mw/aiwvariant.h
branchSymbian2
changeset 2 2fe1408b6811
parent 1 666f914201fb
child 4 837f303aceeb
--- a/epoc32/include/mw/aiwvariant.h	Tue Nov 24 13:55:44 2009 +0000
+++ b/epoc32/include/mw/aiwvariant.h	Tue Mar 16 16:12:26 2010 +0000
@@ -1,1 +1,453 @@
-aiwvariant.h
+/*
+* Copyright (c) 2003-2005 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
+* which accompanies this distribution, and is available
+* at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:     Variant data type for AIW generic parameters.
+*
+*/
+
+
+
+
+
+#ifndef AIW_VARIANT_H
+#define AIW_VARIANT_H
+
+// INCLUDES
+#include <e32std.h>
+#include <s32strm.h>
+#include <f32file.h>
+#include "aiwvarianttype.hrh"
+
+// FORWARD DECLARATIONS
+
+// CLASS DECLARATION
+
+/**
+* Variant data class to hold a value of a TAiwGenericParam instance.
+* The variant contains a data type and a value. This class is attached to
+* TAiwGenericParam instance which holds the semantic type of the value.
+*
+* @lib ServiceHandler.lib
+* @since Series 60 2.6
+* @see TAiwGenericParam
+*/
+class TAiwVariant
+    {
+    public:  // Constructors
+        /**
+        * Default constructor. Initializes this variant to be empty.
+        *
+        * @post IsEmpty()
+        */
+        inline TAiwVariant();
+        
+        /**
+        * Constructor from a value.
+        *
+        * @param aValue The value to set for this variant object.
+        */
+        inline TAiwVariant(TInt32 aValue);
+        
+        /**
+        * Constructor from a value.
+        *
+        * @param aValue The value to set for this variant object.
+        */        
+        inline TAiwVariant(const TUid& aValue);
+        
+        /**
+        * Constructor from a value.
+        *
+        * @param aValue The value to set for this variant object.
+        */        
+        inline TAiwVariant(const TTime& aValue);
+        
+        /**
+        * Constructor from a value.
+        *
+        * @param aValue The value to set for this variant object.
+        */        
+        inline TAiwVariant(const TDesC& aValue);
+        
+        /**
+        * Constructor from a value.
+        *
+        * @param aValue The value to set for this variant object.
+        */        
+        inline TAiwVariant(const HBufC* aValue);
+        
+        /**
+        * Constructor from a value.
+        *
+        * @param aValue The value to set for this variant object.
+        */        
+        inline TAiwVariant(const TDesC8& aValue);
+        
+        /**
+        * Constructor from a value.
+        *
+        * @param aValue The value to set for this variant object.
+        */        
+        inline TAiwVariant(const RFile& aValue);
+
+        /**
+        * Copy constructor. Does not take ownership of data.
+        *
+        * @param aSrc The source object.
+        */
+        IMPORT_C TAiwVariant(const TAiwVariant& aSrc);
+                
+        /**
+        * Assignment operator. Does not take ownership of data.
+        *
+        * @param aValue The source object.
+        */
+        IMPORT_C TAiwVariant& TAiwVariant::operator=(const TAiwVariant& aValue);
+
+        // This class does not need a destructor because memory allocation
+        // policy for variant class has been implemented by TAiwGenericParam
+        // class.
+
+    public:  // Interface
+        /**
+        * Returns the type id of data this variant object is holding.
+        */
+        inline TVariantTypeId TypeId() const;
+
+        /**
+        * Returns ETrue if this variant is empty (it does not hold any value).
+        */
+        inline TBool IsEmpty() const;
+
+        /**
+        * Retrieves the value held by this variant.
+        *
+        * @param aValue If this variant's type does not match the
+        *               parameter type, the parameter will not be modified.
+        * @return ETrue if aValue was set, EFalse if types did not match.
+        */
+        IMPORT_C TBool Get(TInt32& aValue) const;
+        
+        /**
+        * Retrieves the value held by this variant.
+        *
+        * @param aValue If this variant's type does not match the
+        *               parameter type, the parameter will not be modified.
+        * @return ETrue if aValue was set, EFalse if types did not match.
+        */        
+        IMPORT_C TBool Get(TUid& aValue)   const;
+        
+        /**
+        * Retrieves the value held by this variant.
+        *
+        * @param aValue If this variant's type does not match the
+        *               parameter type, the parameter will not be modified.
+        * @return ETrue if aValue was set, EFalse if types did not match.
+        */        
+        IMPORT_C TBool Get(TPtrC& aValue)  const;
+        
+        /**
+        * Retrieves the value held by this variant.
+        *
+        * @param aValue If this variant's type does not match the
+        *               parameter type, the parameter will not be modified.
+        * @return ETrue if aValue was set, EFalse if types did not match.
+        */        
+        IMPORT_C TBool Get(TTime& aValue)  const;
+        
+        /**
+        * Retrieves the value held by this variant.
+        *
+        * @param aValue If this variant's type does not match the
+        *               parameter type, the parameter will not be modified.
+        * @return ETrue if aValue was set, EFalse if types did not match.
+        */        
+        IMPORT_C TBool Get(TPtrC8& aValue) const;
+        
+        /**
+        * Retrieves the value held by this variant.
+        *
+        * @param aValue If this variant's type does not match the
+        *               parameter type, the parameter will not be modified.
+        * @return ETrue if aValue was set, EFalse if types did not match.
+        */        
+        IMPORT_C TBool Get(RFile& aValue) const;
+
+        /**
+        * Returns the value held by this variant.
+        *
+        * @return The value held by this variant. If the data type does not
+        *         match the function, the default initialized data is returned.
+        */
+        IMPORT_C TInt32 AsTInt32() const;
+        
+        /**
+        * Returns the value held by this variant.
+        *
+        * @return The value held by this variant. If the data type does not
+        *         match the function, the default initialized data is returned.
+        */        
+        IMPORT_C TUid AsTUid() const;
+        
+        /**
+        * Returns the value held by this variant.
+        *
+        * @return The value held by this variant. If the data type does not
+        *         match the function, the default initialized data is returned.
+        */        
+        IMPORT_C TPtrC AsDes() const;
+        
+        /**
+        * Returns the value held by this variant.
+        *
+        * @return The value held by this variant. If the data type does not
+        *         match the function, the default initialized data is returned.
+        */        
+        IMPORT_C TTime AsTTime() const;
+        
+        /**
+        * Returns the value held by this variant.
+        *
+        * @return The value held by this variant. If the data type does not
+        *         match the function, the default initialized data is returned.
+        */        
+        IMPORT_C TPtrC8 AsData() const; 
+        
+        /**
+        * Returns the value held by this variant.
+        *
+        * @return The value held by this variant. If the data type does not
+        *         match the function, the default initialized data is returned.
+        */        
+        IMPORT_C RFile AsFileHandle() const;
+
+        /**
+        * Deletes possibly set value and resets this variant to empty.
+        *
+        * @post IsEmpty()
+        */
+        IMPORT_C void Reset();
+
+        /**
+        * Sets integer value to this variant. The previous value is overwritten.
+        *
+        * @param aValue Value for this variant object to hold.
+        * @post *this == aValue
+        */
+        IMPORT_C void Set(TInt32 aValue);
+
+        /**
+        * Sets unique ID value to this variant. The previous value is overwritten.
+        *
+        * @param aValue Value for this variant object to hold.
+        * @post *this == aValue
+        */
+        IMPORT_C void Set(const TUid& aValue);
+        
+        /**
+        * Sets date and time value to this variant. The previous value is overwritten.
+        *
+        * @param aValue Value for this variant object to hold.
+        * @post *this == aValue
+        */
+        IMPORT_C void Set(const TTime& aValue);
+
+        /**
+        * Sets constant text reference to this variant. 
+        *
+        * @param aValue Text value for this variant object to hold.
+        * @post *this == aValue
+        */
+        IMPORT_C void Set(const TDesC& aValue);
+
+        /**
+        * Sets constant text reference to this variant. 
+        *
+        * @param aValue Text value for this variant object to hold. 
+        *               Ownership is not taken.
+        */
+        inline void Set(const HBufC* aValue);
+
+        /**
+        * Sets constant 8-bit text reference to this variant.
+        * 
+        * @param aValue Text value for this variant object to hold.
+        * @post *this == aValue
+        */
+        IMPORT_C void Set(const TDesC8& aValue);
+
+        /**
+        * Sets RFile file handle to this variant.
+        *
+        * @param aValue File handle for this variant object to hold.
+        * @post *this == aValue
+        */
+        IMPORT_C void Set(const RFile& aValue);
+
+        /**
+        * Assignment operator for the variant.
+        *
+        * @param aValue The source object.
+        */
+        inline TAiwVariant& operator=(const TTime& aValue);
+
+        /**
+        * Assignment operator for the variant.
+        *
+        * @param aValue The source object.
+        */        
+        inline TAiwVariant& operator=(const TUid& aValue);
+        
+        /**
+        * Assignment operator for the variant.
+        *
+        * @param aValue The source object.
+        */        
+        inline TAiwVariant& operator=(TInt32 aValue);
+        
+        /**
+        * Assignment operator for the variant.
+        *
+        * @param aValue The source object.
+        */        
+        inline TAiwVariant& operator=(const TDesC& aValue);
+        
+        /**
+        * Assignment operator for the variant.
+        *
+        * @param aValue The source object.
+        */        
+        inline TAiwVariant& operator=(const HBufC* aValue);
+        
+        /**
+        * Assignment operator for the variant.
+        *
+        * @param aValue The source object.
+        */        
+        inline TAiwVariant& operator=(const TDesC8& aValue);
+        
+        /**
+        * Assignment operator for the variant.
+        *
+        * @param aValue The source object.
+        */        
+        inline TAiwVariant& operator=(const RFile& aValue);
+        
+    private:
+        /**
+        * Streaming support for TAiwGenericParam.
+        * Internalizes this variant from a stream.
+        */
+        void InternalizeL(RReadStream& aStream);
+
+        /**
+        * Streaming support for TAiwGenericParam.
+        * Externalizes this variant to a stream.
+        */
+        void ExternalizeL(RWriteStream& aStream) const;
+
+        /**
+        * Streaming support for TAiwGenericParam.
+        * Returns the maximum externalized size of this variant in bytes.
+        */
+        TInt Size() const; 
+
+        /**
+        * Data copying support for TAiwGenericParam.
+        * Sets the copy of given variant value to this variant
+        * @param aValue variant value for this variant object to hold.
+        * @post *this == aValue
+        */
+        void SetL(const TAiwVariant& aValue);
+
+        /**
+        * Destroys any dynamic resource owned by this variant.
+        */
+        void Destroy();
+
+        /// Debug invariant
+        void __DbgTestInvariant() const;
+        
+    private:  // Data
+        /// Type of the data this variant is holding
+        TUint8 iTypeId;
+
+        /// POD storage for a 64-bit integer
+        struct SInt64
+            {
+            TInt32 iLow;
+            TInt32 iHigh;
+            void InternalizeL(RReadStream& aStream);
+            void ExternalizeL(RWriteStream& aStream) const;
+            void Set(const TInt64& aTInt64);
+            operator TInt64() const;
+            TBool operator==(const SInt64& aRhs) const;
+            };
+
+        // Data value stored in this variant.
+        // One of these are effective at a time depending on the iTypeId
+        //
+        union UData
+            {
+            TInt32 iInt32;      // 32-bit integer
+            SInt64 iInt64;      // 64-bit integer
+            HBufC* iBufC;       // owned string pointer 
+            HBufC8* iBufC8;     // owned 8-bit data pointer 
+            };
+
+        UData  iData;  // Data union
+        TPtrC  iPtrC;  // Pointer to string
+        TPtrC8 iPtrC8; // Pointer to 8-bit data 
+
+    private:  // friend declarations
+        friend IMPORT_C TBool operator==(const TAiwVariant& aLhs, const TAiwVariant& aRhs);
+        /// TAiwGenericParam needs access to private streaming and copying methods.
+        friend class TAiwGenericParam;
+        
+    };
+
+
+// FUNCTIONS
+
+/**
+* Returns ETrue if two variants are equal.
+*
+* @param aLhs Left hand side.
+* @param aRhs Right hand side.
+* @return ETrue if equal, EFalse otherwise.
+*/
+IMPORT_C TBool operator==(const TAiwVariant& aLhs, const TAiwVariant& aRhs);
+
+/**
+* Returns ETrue if two variants are not equal.
+*
+* @param aLhs Left hand side.
+* @param aRhs Right hand side.
+* @return ETrue if not equal, EFalse otherwise.
+*/
+inline TBool operator!=(const TAiwVariant& aLhs, const TAiwVariant& aRhs);
+
+/**
+* Dumps the contents of aVariant to debug output. Available only in debug builds.
+*
+* @param aVariant The object to be dumped.
+*/
+void Dump(const TAiwVariant& aVariant);
+
+
+// INLINE FUNCTIONS
+#include "aiwvariant.inl"
+
+#endif // AIW_VARIANT_H
+
+// End of File