net.sf.saxon.pull
public class VirtualTreeWalker extends Object implements PullProvider, NamespaceDeclarations
The tree is physically constructed if operations are requested that depend on the identity of the nodes in the tree, or that navigate within the tree. Operations such as copying or atomizing the tree can be done directly, without building it in memory. (Note however that if such operations are done more than once, the underlying instructions may be evaluated repeatedly.)
Constructor Summary | |
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VirtualTreeWalker(ParentNodeConstructor instruction, XPathContext context)
Create a VirtualTreeWalker to navigate the tree constructed by evaluating a given instruction
in a given dyamic context |
Method Summary | |
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void | close()
Close the event reader. |
int | current()
Get the event most recently returned by next(), or by other calls that change
the position, for example getStringValue() and skipToMatchingEnd(). |
AtomicValue | getAtomicValue()
Get an atomic value. |
AttributeCollection | getAttributes()
Get the attributes associated with the current element. |
int | getFingerprint()
Get the fingerprint of the name of the element. |
int | getNameCode()
Get the nameCode identifying the name of the current node. |
NamePool | getNamePool()
Get the namepool |
int | getNamespaceCode(int index)
Get the n'th declaration in the list in the form of a namespace code. |
int[] | getNamespaceCodes(int[] buffer)
Get all the namespace codes, as an array.
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NamespaceDeclarations | getNamespaceDeclarations()
Get the namespace declarations associated with the current element. |
int | getNumberOfNamespaces()
Get the number of declarations (and undeclarations) in this list. |
PipelineConfiguration | getPipelineConfiguration()
Get configuration information. |
String | getPrefix(int index)
Get the prefix of the n'th declaration (or undeclaration) in the list,
counting from zero.
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SourceLocator | getSourceLocator()
Get the location of the current event.
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CharSequence | getStringValue()
Get the string value of the current element, text node, processing-instruction,
or top-level attribute or namespace node, or atomic value.
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int | getTypeAnnotation()
Get the type annotation of the current attribute or element node, or atomic value.
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String | getURI(int index)
Get the namespace URI of the n'th declaration (or undeclaration) in the list,
counting from zero.
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int | next()
Get the next event
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void | setNameCode(int nameCode)
Set the initial nameCode (the nameCode of the node at the root of the tree being walked) |
void | setPipelineConfiguration(PipelineConfiguration pipe)
Set configuration information. |
int | skipToMatchingEnd()
Skip the current subtree. |
Parameters: instruction the instruction (this will always be an instruction that creates element or document nodes) context the dynamic evaluation context
Returns: the current event
Attributes may be read before or after reading the namespaces of an element, but must not be read after the first child node has been read, or after calling one of the methods skipToEnd(), getStringValue(), or getTypedValue().
Returns: an AttributeCollection representing the attributes of the element that has just been notified.
Returns: the fingerprint. The fingerprint can be used to obtain the local name and namespace URI from the name pool.
Returns: the nameCode. The nameCode can be used to obtain the prefix, local name, and namespace URI from the name pool.
Parameters: index the index identifying which declaration is required.
Returns: the namespace code. This is an integer whose upper half indicates the prefix (0 represents the default namespace), and whose lower half indicates the URI (0 represents an undeclaration).
Throws: IndexOutOfBoundsException if the index is out of range.
Parameters: buffer a sacrificial array that the method is free to use to contain the result. May be null.
Returns: an integer array containing namespace codes. The array may be filled completely with namespace codes, or it may be incompletely filled, in which case a -1 integer acts as a terminator.
It is permissible for this method to return namespace declarations that are redundant.
The NamespaceDeclarations object is guaranteed to remain unchanged until the next START_ELEMENT event, but may then be overwritten. The object should not be modified by the client.
Namespaces may be read before or after reading the attributes of an element, but must not be read after the first child node has been read, or after calling one of the methods skipToEnd(), getStringValue(), or getTypedValue().
*Parameters: index the index identifying which declaration is required.
Returns: the namespace prefix. For a declaration or undeclaration of the default namespace, this is the zero-length string.
Throws: IndexOutOfBoundsException if the index is out of range.
In other situations the result is undefined and may result in an IllegalStateException.
If the most recent event was a VirtualTreeWalker, this method causes the content of the element to be read. The current event on completion of this method will be the corresponding VirtualTreeWalker. The next call of next() will return the event following the END_ELEMENT event.
Returns: the String Value of the node in question, defined according to the rules in the XPath data model.
Returns: the type annotation. This code is the fingerprint of a type name, which may be resolved to a SchemaType by access to the Configuration.
Parameters: index the index identifying which declaration is required.
Returns: the namespace URI. For a namespace undeclaration, this is the zero-length string.
Throws: IndexOutOfBoundsException if the index is out of range.
Returns: an integer code indicating the type of event. The code VirtualTreeWalker is returned at the end of the sequence.
Throws: IllegalStateException if the method is called at any time other than immediately after a START_DOCUMENT or START_ELEMENT event.