uk.ac.sheffield.jast.filter

Class OrFilter

java.lang.Object

uk.ac.sheffield.jast.filter.Filter

uk.ac.sheffield.jast.filter.OrFilter

public class OrFilter
extends Filter

OrFilter is a compound filter applying the logical-OR of two filters. An OrFilter is a kind of Filter that represents the logical disjunction of two other Filters. It accepts nodes which are accepted by either of the component Filters. When any Filter is conjoined with another disparate kind of Filter using the or(Filter) method, this creates and returns a compound OrFilter with this and the other Filter as its components.

OrFilter has an accept(Content) method that returns true, if either of the component Filters return true, when applied to the same Content node. Short-circuit evaluation ensures that the method terminates as soon as the outcome is logically determined. The component Filters are applied in the order they were supplied at construction.

Version:

2.5

Author:

Anthony J H Simons

Field Summary

Fields

Modifier and Type	Field and Description
private Filter	first The first Filter in the combination.
private Filter	second The second Filter in the combination.

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

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

Constructor Summary

Constructors

Constructor and Description
OrFilter(Filter first, Filter second) Constructs a OrFilter accepting the logical-OR of the patterns expressed by the first and second Filters.

Method Summary

Modifier and Type	Method and Description
boolean	accept(Content node) Reports whether a given Content node is accepted by this OrFilter.
protected OrFilter	andNodeFilter(NodeFilter other) Creates a Filter that is the logical-AND of this OrFilter and a NodeFilter.
java.lang.String	toString() Returns a pretty representation of this Filter.

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

and, andIndexFilter, not, or, orNodeFilter

Methods inherited from class java.lang.Object

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

Field Detail

first

private Filter first

The first Filter in the combination. This filter is always applied first.

second

private Filter second

The second Filter in the combination. This filter is always applied second.

Constructor Detail

OrFilter

public OrFilter(Filter first,
                Filter second)

Constructs a OrFilter accepting the logical-OR of the patterns expressed by the first and second Filters. The created OrFilter will apply the first Filter and only apply the second Filter if the first Filter rejects the tested node.

Parameters:

first - a Filter.

second - a Filter.

Method Detail

accept

public boolean accept(Content node)

Reports whether a given Content node is accepted by this OrFilter. Returns true if either the first or second component Filters accept the Content node, otherwise returns false. The first Filter is always applied and then the second Filter is only applied if the first Filter has rejected the tested node.

Specified by:

accept in class Filter

Parameters:

node - a Content node.

Returns:

true, if the node is accepted, otherwise false.

andNodeFilter

protected OrFilter andNodeFilter(NodeFilter other)

Creates a Filter that is the logical-AND of this OrFilter and a NodeFilter. Replaces this OrFilter with another OrFilter, in which the NodeFilter constraint has been propagated to each component Filter. This is potentially more efficient than creating a nested AndFilter.

Overrides:

andNodeFilter in class Filter

Parameters:

other - the other NodeFilter.

Returns:

a new Filter.

toString

public java.lang.String toString()

Returns a pretty representation of this Filter. Returns the name of this OrFilter, with brackets surrounding the nested Filters.

Overrides:

toString in class Filter