public interface XMPIterator
XMPMeta iteration services.
XMPIterator provides a uniform means to iterate over the
schema and properties within an XMP object.
The iteration over the schema and properties within an XMP object is very
complex. It is helpful to have a thorough understanding of the XMP data tree.
One way to learn this is to create some complex XMP and examine the output of
XMPMeta#toString. This is also described in the XMP
Specification, in the XMP Data Model chapter.
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
XMPIterator#next()). Beneath the root are
schema nodes. These are just collectors for 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.
XMPIterator is created by XMPMeta#interator() constructor
defines a starting point for the iteration and options that control how it
proceeds. By default the iteration starts at the root and visits all nodes
beneath it in a depth first manner. The root node 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.
XMPIterator#next() method 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.
The options to control the iteration are:
XMPPropertyInfo-objects and throws
NoSuchElementException if there are no more properties to
|Modifier and Type
|Method and Description
Skip the subtree below and remaining siblings of the current node when
next() is called.
Skip the subtree below the current node when
Copyright © 2010 - 2020 Adobe. All Rights Reserved