TXMPIterator< tStringObj > Class Template Reference

API for access to the XMP Toolkit iteration services. More...

#include <TXMPIterator.hpp>

Public Member Functions
void	operator= (const TXMPIterator< tStringObj > &rhs)
	Assignment operator, assigns the internal ref and increments the ref count. More...
	TXMPIterator (const TXMPIterator< tStringObj > &original)
	Copy constructor, creates a client object refering to the same internal object. More...
	TXMPIterator (const TXMPMeta< tStringObj > &xmpObj, XMP_StringPtr schemaNS, XMP_StringPtr propName, XMP_OptionBits options=0)
	Constructs an iterator for properties within a schema in an XMP object. More...
	TXMPIterator (const TXMPMeta< tStringObj > &xmpObj, XMP_StringPtr schemaNS, XMP_OptionBits options=0)
	Constructs an iterator for a subtree of properties within an XMP object. More...
	TXMPIterator (const TXMPMeta< tStringObj > &xmpObj, XMP_OptionBits options=0)
	Constructs an iterator for the entire data tree within an XMP object. More...
	TXMPIterator (XMP_StringPtr schemaNS, XMP_StringPtr propName, XMP_OptionBits options)
	Constructs an iterator for the global tables of the XMP toolkit. Not implemented. More...
virtual	~TXMPIterator () throw ()
	Destructor, typical virtual destructor. More...
bool	Next (tStringObj *schemaNS=0, tStringObj *propPath=0, tStringObj *propValue=0, XMP_OptionBits *options=0)
	Next() visits the next node in the iteration. More...
void	Skip (XMP_OptionBits options)
	Skip() skips some portion of the remaining iterations. More...

Private Member Functions
	TXMPIterator ()

Static Private Member Functions
static void	SetClientString (void *clientPtr, XMP_StringPtr valuePtr, XMP_StringLen valueLen)

Private Attributes
XMPIteratorRef	iterRef

Detailed Description

template<class tStringObj>
class TXMPIterator< tStringObj >

API for access to the XMP Toolkit iteration services.

TXMPIterator provides a uniform means to iterate over the schema and properties within an XMP object. TXMPIterator is a template class which must be instantiated with a string class such as std::string. See the instructions in XMP.hpp, and the Overview for a discussion of the overall architecture of the XMP API. Access these functions through the concrete class, SXMPIterator.

Note

Only XMP object iteration is currently available. Future development may include iteration over global tables, such as registered namespaces.

To understand how iteration works, you should have a thorough understanding of the XMP data tree, as described in the XMP Specification Part 1. You might also find it helpful to create some complex XMP and examine the output of TXMPMeta::DumpObject().

• The top of the XMP data tree is a single root node. This does not explicitly appear in the dump and is never visited by an iterator; that is, it is never returned from TXMPIterator::Next().

• Beneath the root are schema nodes; these collect the top-level properties in the same namespace. They are created and destroyed implicitly.

• Beneath the schema nodes are the property nodes. The nodes below a property node depend on its type (simple, struct, or array) and whether it has qualifiers.

A TXMPIterator constructor defines a starting point for the iteration, and options that control how it proceeds. By default, iteration starts at the root and visits all nodes beneath it in a depth-first manner. The root node iteself is not visited; the first visited node is a schema node. You can provide a schema name or property path to select a different starting node. By default, this visits the named root node first then all nodes beneath it in a depth-first manner.

The function TXMPIterator::Next() delivers the schema URI, path, and option flags for the node being visited. If the node is simple, it also delivers the value. Qualifiers for this node are visited next. The fields of a struct or items of an array are visited after the qualifiers of the parent.

You can specify options when contructing the iteration object to control how the iteration is performed.

• kXMP_IterJustChildren - Visit just the immediate children of the root. Skip the root itself and all nodes below the immediate children. This omits the qualifiers of the immediate children, the qualifier nodes being below what they qualify.
• kXMP_IterJustLeafNodes - Visit just the leaf property nodes and their qualifiers.
• kXMP_IterJustLeafName - Return just the leaf component of the node names. The default is to return the full path name.
• kXMP_IterOmitQualifiers - Do not visit the qualifiers of a node.

Definition at line 79 of file TXMPIterator.hpp.

Constructor & Destructor Documentation

template<class tStringObj>

TXMPIterator< tStringObj >::TXMPIterator

(

const TXMPIterator< tStringObj > &

original

)

Copy constructor, creates a client object refering to the same internal object.

Creates a new client iterator that refers to the same underlying iterator as an existing object.

Parameters

original

An existing iteration object to copy.

template<class tStringObj>

TXMPIterator< tStringObj >::TXMPIterator	(	const TXMPMeta< tStringObj > &	xmpObj,
		XMP_StringPtr	schemaNS,
		XMP_StringPtr	propName,
		XMP_OptionBits	options = 0
	)

Constructs an iterator for properties within a schema in an XMP object.

See the class description for the general operation of an XMP object iterator. Overloaded forms are provided to iterate the entire data tree, a subtree rooted at a specific node, or properties within a specific schema.

Parameters

xmpObj	The XMP object over which to iterate.
schemaNS	Optional schema namespace URI to restrict the iteration. To visit all of the schema, pass 0 or the empty string "".
propName	Optional property name to restrict the iteration. May be an arbitrary path expression. If provided, a schema URI must also be provided. To visit all properties, pass 0 or the empty string "".
options	Option flags to control the iteration. A logical OR of these bit flag constants: kXMP_IterJustChildren - Visit only the immediate children of the root; default visits subtrees. kXMP_IterJustLeafNodes - Visit only the leaf nodes; default visits all nodes. kXMP_IterJustLeafName - Return just the leaf part of the path; default returns the full path. kXMP_IterOmitQualifiers - Omit all qualifiers.

Returns

The new TXMPIterator object.

template<class tStringObj>

TXMPIterator< tStringObj >::TXMPIterator	(	const TXMPMeta< tStringObj > &	xmpObj,
		XMP_StringPtr	schemaNS,
		XMP_OptionBits	options = 0
	)

Constructs an iterator for a subtree of properties within an XMP object.

See the class description for the general operation of an XMP object iterator. Overloaded forms are provided to iterate the entire data tree, a subtree rooted at a specific node, or properties within a specific schema.

Parameters

xmpObj	The XMP object over which to iterate.
schemaNS	Optional schema namespace URI to restrict the iteration. To visit all of the schema, pass 0 or the empty string "".
options	Option flags to control the iteration. A logical OR of these bit flag constants: kXMP_IterJustChildren - Visit only the immediate children of the root; default visits subtrees. kXMP_IterJustLeafNodes - Visit only the leaf nodes; default visits all nodes. kXMP_IterJustLeafName - Return just the leaf part of the path; default returns the full path. kXMP_IterOmitQualifiers - Omit all qualifiers.

Returns

The new TXMPIterator object.

template<class tStringObj>

TXMPIterator< tStringObj >::TXMPIterator	(	const TXMPMeta< tStringObj > &	xmpObj,
		XMP_OptionBits	options = 0
	)

Constructs an iterator for the entire data tree within an XMP object.

See the class description for the general operation of an XMP object iterator. Overloaded forms are provided to iterate the entire data tree, a subtree rooted at a specific node, or properties within a specific schema.

Parameters

xmpObj	The XMP object over which to iterate.
options	Option flags to control the iteration. A logical OR of these bit flag constants: kXMP_IterJustChildren - Visit only the immediate children of the root; default visits subtrees. kXMP_IterJustLeafNodes - Visit only the leaf nodes; default visits all nodes. kXMP_IterJustLeafName - Return just the leaf part of the path; default returns the full path. kXMP_IterOmitQualifiers - Omit all qualifiers.

Returns

The new TXMPIterator object.

template<class tStringObj>

TXMPIterator< tStringObj >::TXMPIterator	(	XMP_StringPtr	schemaNS,
		XMP_StringPtr	propName,
		XMP_OptionBits	options
	)

Constructs an iterator for the global tables of the XMP toolkit. Not implemented.

template<class tStringObj>

virtual TXMPIterator< tStringObj >::~TXMPIterator ( ) throw ( )

virtual

Destructor, typical virtual destructor.

template<class tStringObj>

TXMPIterator< tStringObj >::TXMPIterator ( )

private

Member Function Documentation

template<class tStringObj>

bool TXMPIterator< tStringObj >::Next	(	tStringObj *	schemaNS = 0,
		tStringObj *	propPath = 0,
		tStringObj *	propValue = 0,
		XMP_OptionBits *	options = 0
	)

Next() visits the next node in the iteration.

Proceeds to the next node according to the options specified on creation of this object, and delivers the schema URI, path, and option flags for the node being visited. If the node is simple, it also delivers the value.

Parameters

schemaNS	[out] A string object in which to return the assigned the schema namespace URI of the current property. Can be null if the value is not wanted.
propPath	[out] A string object in which to return the XPath name of the current property. Can be null if the value is not wanted.
propValue	[out] A string object in which to return the value of the current property. Can be null if the value is not wanted.
options	[out] A buffer in which to return the flags describing the current property, which are a logical OR of XMP_OptionBits bit-flag constants.

Returns

True if there was another node to visit, false if the iteration is complete.

template<class tStringObj>

void TXMPIterator< tStringObj >::operator=

(

const TXMPIterator< tStringObj > &

rhs

)

Assignment operator, assigns the internal ref and increments the ref count.

Assigns the internal reference from an existing object and increments the reference count on the underlying internal XMP iterator.

Parameters

rhs	An existing iteration object.

template<class tStringObj>

static void TXMPIterator< tStringObj >::SetClientString ( void *  clientPtr, XMP_StringPtr  valuePtr, XMP_StringLen  valueLen  )

staticprivate

template<class tStringObj>

void TXMPIterator< tStringObj >::Skip

(

XMP_OptionBits

options

)

Skip() skips some portion of the remaining iterations.

Parameters

options

Option flags to control the iteration, a logical OR of these bit-flag constants: kXMP_IterSkipSubtree - Skip the subtree below the current node. kXMP_IterSkipSiblings - Skip the subtree below and remaining siblings of the current node.

Member Data Documentation

template<class tStringObj>

XMPIteratorRef TXMPIterator< tStringObj >::iterRef

private

Definition at line 225 of file TXMPIterator.hpp.

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

• C:/XMP/XMP-Toolkit-SDK-CC201607/XMP-Toolkit-SDK-CC201607/public/include/TXMPIterator.hpp