Base class for all Exiv2 values used to store XMP property values. More...

#include <value.hpp>

Inheritance diagram for Exiv2::XmpValue:

[legend]

Public Types
enum	XmpArrayType { xaNone, xaAlt, xaBag, xaSeq }
	XMP array types.

enum	XmpStruct { xsNone, xsStruct }
	XMP structure indicator.

typedef std::auto_ptr< XmpValue >	AutoPtr
	Shortcut for a XmpValue auto pointer.

Public Types inherited from Exiv2::Value
typedef std::auto_ptr< Value >	AutoPtr
	Shortcut for a Value auto pointer.

Public Member Functions
Creators
	XmpValue (TypeId typeId)

Accessors
XmpArrayType	xmpArrayType () const
	Return XMP array type, indicates if an XMP value is an array.

XmpStruct	xmpStruct () const
	Return XMP struct, indicates if an XMP value is a structure.

virtual long	size () const
	Return the size of the value in bytes.

virtual long	copy (byte *buf, ByteOrder byteOrder=invalidByteOrder) const
	Write value to a character data buffer. More...

Public Member Functions inherited from Exiv2::Value
	Value (TypeId typeId)
	Constructor, taking a type id to initialize the base class with.

virtual	~Value ()
	Virtual destructor.

virtual int	setDataArea (const byte *buf, long len)
	Set the data area, if the value has one by copying (cloning) the buffer pointed to by buf. More...

TypeId	typeId () const
	Return the type identifier (Exif data format type).

AutoPtr	clone () const
	Return an auto-pointer to a copy of itself (deep copy). The caller owns this copy and the auto-pointer ensures that it will be deleted.

virtual long	count () const =0
	Return the number of components of the value.

virtual std::ostream &	write (std::ostream &os) const =0
	Write the value to an output stream. You do not usually have to use this function; it is used for the implementation of the output operator for Value, operator<<(std::ostream &os, const Value &value).

std::string	toString () const
	Return the value as a string. Implemented in terms of write(std::ostream& os) const of the concrete class.

virtual std::string	toString (long n) const
	Return the n-th component of the value as a string. The default implementation returns toString(). The behaviour of this method may be undefined if there is no n-th component.

virtual long	toLong (long n=0) const =0
	Convert the n-th component of the value to a long. The behaviour of this method may be undefined if there is no n-th component. More...

virtual float	toFloat (long n=0) const =0
	Convert the n-th component of the value to a float. The behaviour of this method may be undefined if there is no n-th component. More...

virtual Rational	toRational (long n=0) const =0
	Convert the n-th component of the value to a Rational. The behaviour of this method may be undefined if there is no n-th component. More...

virtual long	sizeDataArea () const
	Return the size of the data area, 0 if there is none.

virtual DataBuf	dataArea () const
	Return a copy of the data area if the value has one. The caller owns this copy and DataBuf ensures that it will be deleted. More...

bool	ok () const
	Check the ok status indicator. After a to<Type> conversion, this indicator shows whether the conversion was successful.

Manipulators
void	setXmpArrayType (XmpArrayType xmpArrayType)
	Set the XMP array type to indicate that an XMP value is an array.

void	setXmpStruct (XmpStruct xmpStruct=xsStruct)
	Set the XMP struct type to indicate that an XMP value is a structure.

virtual int	read (const byte *buf, long len, ByteOrder byteOrder=invalidByteOrder)
	Read the value from a character buffer. More...

virtual int	read (const std::string &buf)=0
	Set the value from a string buffer. The format of the string corresponds to that of the write() method, i.e., a string obtained through the write() method can be read by this function. More...

static XmpArrayType	xmpArrayType (TypeId typeId)
	Return XMP array type for an array Value TypeId, xaNone if typeId is not an XMP array value type.

XmpValue &	operator= (const XmpValue &rhs)
	Assignment operator. Protected so that it can only be used by subclasses but not directly.

Additional Inherited Members
Static Public Member Functions inherited from Exiv2::Value
static AutoPtr	create (TypeId typeId)
	A (simple) factory to create a Value type. More...

Protected Member Functions inherited from Exiv2::Value
Value &	operator= (const Value &rhs)
	Assignment operator. Protected so that it can only be used by subclasses but not directly.

Protected Attributes inherited from Exiv2::Value
bool	ok_
	Indicates the status of the previous to<Type> conversion.

Detailed Description

Base class for all Exiv2 values used to store XMP property values.

Member Function Documentation

◆ copy()

virtual long Exiv2::XmpValue::copy	(	byte *	buf,
		ByteOrder	byteOrder = `invalidByteOrder`
	)		const

virtual

Write value to a character data buffer.

The user must ensure that the buffer has enough memory. Otherwise the call results in undefined behaviour.

Note: The byte order is required by the interface but not used by this method, so just use the default.

Parameters

buf	Data buffer to write to.
byteOrder	Byte order. Not used.

Returns: Number of characters written.

Implements Exiv2::Value.

◆ read() [1/2]

virtual int Exiv2::XmpValue::read	(	const byte *	buf,
		long	len,
		ByteOrder	byteOrder = `invalidByteOrder`
	)

virtual

Read the value from a character buffer.

Uses read(const std::string& buf)

Note: The byte order is required by the interface but not used by this method, so just use the default.

Parameters

buf	Pointer to the data buffer to read from
len	Number of bytes in the data buffer
byteOrder	Byte order. Not needed.

Returns: 0 if successful.

Implements Exiv2::Value.

◆ read() [2/2]

virtual int Exiv2::XmpValue::read ( const std::string & buf )

pure virtual

Set the value from a string buffer. The format of the string corresponds to that of the write() method, i.e., a string obtained through the write() method can be read by this function.

Parameters

buf	The string to read from.

Returns: 0 if successful.

Implements Exiv2::Value.

Implemented in Exiv2::LangAltValue, Exiv2::XmpArrayValue, and Exiv2::XmpTextValue.

The documentation for this class was generated from the following file:

value.hpp

Public Types

Public Member Functions

Manipulators

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ copy()

◆ read() [1/2]

◆ read() [2/2]