org.apache.xalan.lib
Class Extensions

java.lang.Object
  |
  +--org.apache.xalan.lib.Extensions

public class Extensions

extends java.lang.Object

This class contains many of the Xalan-supplied extensions. It is accessed by specifying a namespace URI as follows:

    xmlns:xalan="http://xml.apache.org/xalan"
 

Method Summary

static NodeSet	difference(NodeIterator ni1, NodeIterator ni2) Returns the difference between two node-sets.
static NodeSet	distinct(NodeIterator ni) Returns node-set containing distinct string values.
static XObject	evaluate(ExpressionContext myContext, java.lang.String xpathExpr) Returns the result of evaluating the argument as a string containing an XPath expression.
static boolean	hasSameNodes(NodeIterator ni1, NodeIterator ni2) Returns true of both node-sets contain the same set of nodes.
static NodeSet	intersection(NodeIterator ni1, NodeIterator ni2) Returns the intersection of two node-sets.
static NodeSet	nodeset(ExpressionContext myProcessor, java.lang.Object rtf) This method is an extension that implements as a Xalan extension the node-set function also found in xt and saxon.
static NodeSet	tokenize(ExpressionContext myContext, java.lang.String toTokenize) Returns a NodeSet containing one text node for each token in the first argument.
static NodeSet	tokenize(ExpressionContext myContext, java.lang.String toTokenize, java.lang.String delims) Returns a NodeSet containing one text node for each token in the first argument.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

nodeset

public static NodeSet nodeset(ExpressionContext myProcessor,
                              java.lang.Object rtf)

This method is an extension that implements as a Xalan extension the node-set function also found in xt and saxon. If the argument is a Result Tree Fragment, then nodeset returns a node-set consisting of a single root node as described in section 11.1 of the XSLT 1.0 Recommendation. If the argument is a node-set, nodeset returns a node-set. If the argument is a string, number, or boolean, then nodeset returns a node-set consisting of a single root node with a single text node child that is the result of calling the XPath string() function on the passed parameter. If the argument is anything else, then a node-set is returned consisting of a single root node with a single text node child that is the result of calling the java toString() method on the passed argument. Most of the actual work here is done in MethodResolver and XRTreeFrag.

Parameters:

myProcessor - Context passed by the extension processor

rtf - Argument in the stylesheet to the nodeset extension function

intersection

public static NodeSet intersection(NodeIterator ni1,
                                   NodeIterator ni2)
                            throws TransformerException

Returns the intersection of two node-sets.

Parameters:

n1 - NodeIterator for first node-set

ni2 - NodeIterator for second node-set

Returns:

a NodeSet containing the nodes in ni1 that are also in ni2

difference

public static NodeSet difference(NodeIterator ni1,
                                 NodeIterator ni2)
                          throws TransformerException

Returns the difference between two node-sets.

Parameters:

n1 - NodeIterator for first node-set

ni2 - NodeIterator for second node-set

Returns:

a NodeSet containing the nodes in ni1 that are not in ni2

distinct

public static NodeSet distinct(NodeIterator ni)
                        throws TransformerException

Returns node-set containing distinct string values.

Parameters:

ni - NodeIterator for node-set

Returns:

a NodeSet with nodes from ni containing distinct string values. In other words, if more than one node in ni contains the same string value, only include the first such node found.

hasSameNodes

public static boolean hasSameNodes(NodeIterator ni1,
                                   NodeIterator ni2)

Returns true of both node-sets contain the same set of nodes.

Parameters:

n1 - NodeIterator for first node-set

ni2 - NodeIterator for second node-set

Returns:

true if ni1 and ni2 contain exactly the same set of nodes.

evaluate

public static XObject evaluate(ExpressionContext myContext,
                               java.lang.String xpathExpr)
                        throws SAXNotSupportedException,
                               java.lang.Exception

Returns the result of evaluating the argument as a string containing an XPath expression. Used where the XPath expression is not known until run-time. The expression is evaluated as if the run-time value of the argument appeared in place of the evaluate function call at compile time.

Parameters:

myContext - an ExpressionContext passed in by the extension mechanism. This must be an XPathContext.

xpathExtr - The XPath expression to be evaluated.

Returns:

the XObject resulting from evaluating the XPath

tokenize

public static NodeSet tokenize(ExpressionContext myContext,
                               java.lang.String toTokenize,
                               java.lang.String delims)

Returns a NodeSet containing one text node for each token in the first argument. Delimiters are specified in the second argument. Tokens are determined by a call to StringTokenizer. If the first argument is an empty string or contains only delimiters, the result will be an empty NodeSet. Contributed to XalanJ1 by Benoit Cerrina.

Parameters:

myContext - an ExpressionContext passed in by the extension mechanism. This must be an XPathContext.

toTokenize - The string to be split into text tokens.

delims - The delimiters to use.

Returns:

a NodeSet as described above.

tokenize

public static NodeSet tokenize(ExpressionContext myContext,
                               java.lang.String toTokenize)

Returns a NodeSet containing one text node for each token in the first argument. Delimiters are whitespace. That is, the delimiters that are used are tab ( ), linefeed ( ), return ( ), and space ( ). Tokens are determined by a call to StringTokenizer. If the first argument is an empty string or contains only delimiters, the result will be an empty NodeSet. Contributed to XalanJ1 by Benoit Cerrina.

Parameters:

myContext - an ExpressionContext passed in by the extension mechanism. This must be an XPathContext.

toTokenize - The string to be split into text tokens.

Returns:

a NodeSet as described above.