uk.ac.sheffield.jast.filter

Class XPathFilter

java.lang.Object

uk.ac.sheffield.jast.filter.Filter

uk.ac.sheffield.jast.filter.MaskFilter

uk.ac.sheffield.jast.filter.XPathFilter

public class XPathFilter
extends MaskFilter

XPathFilter is a simple filter for selecting nodes that satisfy an XPath predicate. An XPath predicate is a nested XPath query pattern enclosed in square brackets. An XPathFilter creates an internal XPath object, which compiles the nested query pattern. This XPathFilter matches the nested XPath against the context node, returning false if the recursive search returns an empty list of results; otherwise returns true if the recursive search returns a non-empty list.

XPathFilter has an accept(Content) method, which returns true, if the recursive XPath, when matched against the Content node, returns a non-empty list of Content results. The recursive XPath is created from the predicate query pattern, from which the enclosing square brackets have been stripped away.

Version:

2.5

Author:

Anthony J H Simons

Field Summary

Fields

Modifier and Type	Field and Description
private XPath	xpath The nested XPath query, which is used to match against the context node.

Fields inherited from class uk.ac.sheffield.jast.filter.MaskFilter

mask

Fields inherited from class uk.ac.sheffield.jast.filter.Filter

ALLCONTENT, NAMENODES, PARENTNODES, PROPERTYNODES, VALUENODES, XPATHNODES, XPATHTEXT

Constructor Summary

Constructors

Constructor and Description
XPathFilter() Creates an XPathFilter that will accept any accessible XPath child node.
XPathFilter(java.lang.String pattern) Creates an XPathFilter using the supplied query pattern.

Method Summary

Modifier and Type	Method and Description
boolean	accept(Content node) Reports whether a given Content node is accepted by this XPathFilter.
java.lang.String	toString() Prints a pretty representation of this Filter.

Methods inherited from class uk.ac.sheffield.jast.filter.MaskFilter

getMask

Methods inherited from class uk.ac.sheffield.jast.filter.Filter

and, andIndexFilter, andNodeFilter, not, or, orNodeFilter

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

xpath

private XPath xpath

The nested XPath query, which is used to match against the context node.

Constructor Detail

XPathFilter

public XPathFilter()

Creates an XPathFilter that will accept any accessible XPath child node. This filter accepts any node apart from Declaration or Doctype nodes.

XPathFilter

public XPathFilter(java.lang.String pattern)

Creates an XPathFilter using the supplied query pattern. The pattern must not be null or the empty String.

Parameters:

pattern - an XPath query pattern.

Method Detail

accept

public boolean accept(Content node)

Reports whether a given Content node is accepted by this XPathFilter. The Content node is the context of an existing XPath search. This XPathFilter represents a predicate to be applied to the context. It applies a recursive XPath query and returns true, if the query result is non-empty; otherwise returns false.

Overrides:

accept in class MaskFilter

Parameters:

node - any Content.

Returns:

true, if the nested XPath query succeeds; otherwise false.

toString

public java.lang.String toString()

Prints a pretty representation of this Filter. Prints the name of XPath, with angle brackets surrounding the nested XPathRules.

Overrides:

toString in class Filter