RWDBTBuffer< T > Class Template Reference
[Open SQL]

Template class that encapsulates a fixed-sized array of elements of type T. More...

#include <rw/db/tbuffer.h>

Inheritance diagram for RWDBTBuffer< T >:

List of all members.

Public Member Functions
	RWDBTBuffer (RWSize_T entries=1, RWSize_T width=0)
	RWDBTBuffer (T *data, RWSize_T entries=1, RWSize_T width=0)
	RWDBTBuffer (T *data, RWDBNullIndicator *indicator, RWSize_T entries=1, RWSize_T width=0)
virtual	~RWDBTBuffer ()
const T &	operator[] (size_t index) const
T &	operator[] (size_t index)
void	setData (const T &newData)
void	setData (size_t index, const T &newData)
size_t	entries () const
void	paramType (RWDBColumn::ParamType newType)
RWDBColumn::ParamType	paramType () const
bool	isNull (size_t index) const
void	setNull ()
void	setNull (size_t index)
void	unsetNull ()
void	unsetNull (size_t index)

---

Detailed Description

template<class T>
class RWDBTBuffer< T >

Class RWDBTBuffer<T> encapsulates a fixed-sized array of elements of type T. Memory for these type T elements can be managed explicitly in your applications, or by an RWDBTBuffer<T> itself. In addition, this class keeps a null indicator vector that indicates whether any item in the array is NULL. The class also provides mechanisms for converting buffer items to and from RWDBValue objects, if the chosen type T can be converted.

The parameter T represents the type of object to be inserted into the array, either a class or a fundamental data type. The class T must have:

• Well-defined copy semantics, meaning T::T(const T&) or the equivalent
• Well-defined assignment semantics, meaning T::operator=(const T&) or the equivalent

Note:

To create an instance of RWDBTBuffer with the data type RWUString from the Internationalization Module, you must include the header file <rw/db/tbuffer_ustr.h> instead of <rw/db/tbuffer.h>.

Synopsis

 #include <rw/db/tbuffer.h>

Examples

Please see Example 1 in the entry for RWDBOSql.

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Constructor & Destructor Documentation

template<class T>

RWDBTBuffer< T >::RWDBTBuffer	(	RWSize_T	entries = 1,
		RWSize_T	width = 0
	)			[inline]

Constructs an RWDBTBuffer<T> with entries entries, and width width. Allocates the array of element-type T of length entries, whose memory is managed by self. entries must be greater than or equal to 1. Allocates the array of null indicators, of length entries, and sets them to false. Memory for the null indicator array is managed by self. If width = 0, the object uses the default width for type T.

template<class T>

RWDBTBuffer< T >::RWDBTBuffer	(	T *	data,
		RWSize_T	entries = 1,
		RWSize_T	width = 0
	)			[inline]

Same as RWDBTBuffer(RWSize_T,RWSize_T), but the RWDBTBuffer<T> uses data and does not allocate or manage memory for the array. Also, the null indicator array is set to false, and its memory is managed by self.

template<class T>

RWDBTBuffer< T >::RWDBTBuffer	(	T *	data,
		RWDBNullIndicator *	indicator,
		RWSize_T	entries = 1,
		RWSize_T	width = 0
	)			[inline]

Same as RWDBTBuffer(T*,RWSize_T,RWSize_T), but the RWDBTBuffer<T> uses the null indicator array passed as indicator, and does not allocate or manage memory for the null indicator array.

template<class T>

virtual RWDBTBuffer< T >::~RWDBTBuffer

(

)

[inline, virtual]

Deletes all data owned by self.

---

Member Function Documentation

template<class T>

size_t RWDBTBuffer< T >::entries

(

)

const [inline]

Returns the number of entries.

template<class T>

bool RWDBTBuffer< T >::isNull

(

size_t

index

)

const [inline, virtual]

Performs a bounds check on index in debug mode. Returns true if the index^th entry is NULL.

Reimplemented from RWDBAbstractBuffer.

template<class T>

T& RWDBTBuffer< T >::operator[]

(

size_t

index

)

[inline]

Performs a bounds check on index in debug mode. Returns a reference to the index^th entry in the array. The returned reference may be used as an lvalue. If using this method to assign a new value to this entry, an explicit call to unsetNull(size_t) using index is needed.

Reimplemented in RWDBBinaryVector, RWDBStringVector, and RWDBDecimalVector.

template<class T>

const T& RWDBTBuffer< T >::operator[]

(

size_t

index

)

const [inline]

Performs a bounds check on index in debug mode. Returns the index^th entry in the array by value. The returned reference may be used as an rvalue.

template<class T>

RWDBColumn::ParamType RWDBTBuffer< T >::paramType

(

)

const [inline]

Returns a value indicating the parameter type of the column.

Reimplemented from RWDBAbstractBuffer.

template<class T>

void RWDBTBuffer< T >::paramType

(

RWDBColumn::ParamType

newType

)

[inline]

Changes the paramType attribute of self to newType. By default, the paramType is set to RWDBColumn::inParameter. Note that this does not change the definition of the parameter in the database. Returns a reference to self.

Reimplemented from RWDBAbstractBuffer.

template<class T>

void RWDBTBuffer< T >::setData	(	size_t	index,
		const T &	newData
	)			[inline]

Sets the index^th entry of the array to be newData. Unsets NULL for the index^th entry.

template<class T>

void RWDBTBuffer< T >::setData

(

const T &

newData

)

[inline]

Sets all the contents of the array to be newData. Unsets NULL for each entry.

template<class T>

void RWDBTBuffer< T >::setNull

(

size_t

index

)

[inline, virtual]

Sets NULL at the index^th entry.

Reimplemented from RWDBAbstractBuffer.

template<class T>

void RWDBTBuffer< T >::setNull

(

)

[inline, virtual]

Sets NULL for all entries.

Reimplemented from RWDBAbstractBuffer.

template<class T>

void RWDBTBuffer< T >::unsetNull

(

size_t

index

)

[inline, virtual]

Unsets NULL at the index^th entry.

Reimplemented from RWDBAbstractBuffer.

template<class T>

void RWDBTBuffer< T >::unsetNull

(

)

[inline, virtual]

Unsets NULL for all entries.

Reimplemented from RWDBAbstractBuffer.