com.saxonica.ee.pattern.preconditions

Class ComparisonPredicateIndex

java.lang.Object

com.saxonica.ee.pattern.preconditions.ComparisonPredicateIndex

public class ComparisonPredicateIndex
extends Object

A class containing information for simple indexation of templates rules of the general form base[expr = vals], and the special case for DITA-OT *[contains(@class,' tag ')]

To iterate across candidate rules, the IndexMatcher class can be used, behaving as a sequence iterator to yield successive candidate matching Rules (wrapped in ObjectValue). This stateful iterator can be created via makeRuleSearchState(SimpleMode) and then initialised for processing a specific context item via the IndexMatcher.prepareEval(Item, XPathContext) method.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	ComparisonPredicateIndex.AncestorQualifiedRuleCase A rule case which has ancestral qualification.
class	ComparisonPredicateIndex.IndexBase A class that is used to index sets of rules with common forms, such as patt[expr = value] where patt - the base pattern and expr - the LHS of a comparison are common By matching instances of this class we can group rules that have similar 'left hand sides' for indexation
class	ComparisonPredicateIndex.RuleCase A class to contain a rule (held as an ObjectValue, which is an Item) and a possible matching condition
class	ComparisonPredicateIndex.RuleIndex A class to contain a list of rules indexed against a set of atomic value match keys.
class	ComparisonPredicateIndex.ValueObject<R> A class to encapsulate an atomic value and associated Object (usually a Rule)

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_MIN_RULES
Map<ComparisonPredicateIndex.IndexBase,ComparisonPredicateIndex.RuleIndex>	indicies

Constructor Summary

Constructors

Constructor and Description
ComparisonPredicateIndex()

Method Summary

Methods

Modifier and Type	Method and Description
void	add(Rule r) Add a rule to a simple index if possible
void	explain(ExpressionPresenter out)
IndexMatcher	makeRuleSearchState(SimpleMode mode)
com.saxonica.ee.pattern.preconditions.ComparisonPredicateIndex.IndexAndRHS	maybeDITAIndexable(AncestorQualifiedPattern p) Determine whether this AncestorQualifiedPattern can be indexed against the semantics of DITA-OT stylesheets and if so return a suitable index/value pair
com.saxonica.ee.pattern.preconditions.ComparisonPredicateIndex.IndexAndRHS	maybeDITAIndexable(PatternWithPredicate p) Determine whether this pattern can be indexed against the semantics of DITA-OT stylesheets and if so return a suitable indexation index/value pair.
com.saxonica.ee.pattern.preconditions.ComparisonPredicateIndex.IndexAndRHS	maybeIndexable(AncestorQualifiedPattern p) Determine whether this AncestorQualifiedPattern can be indexed and if so return a suitable index/value pair Note that only the base pattern is used in the index; the upper pattern is associated with the rule and is attached to the rule list members - in this way flat and ancestor-qualified patterns that share the same base (e.g.
void	optimize() Optimize the indicies - in fact it is essential this is executed, to form up the internal indexes.
void	setDita(boolean dita) Enable DITA-OT optimization
void	setMinRules(int minRules)
int	size()

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MIN_RULES

public static int DEFAULT_MIN_RULES

indicies

public Map<ComparisonPredicateIndex.IndexBase,ComparisonPredicateIndex.RuleIndex> indicies

Constructor Detail

ComparisonPredicateIndex

public ComparisonPredicateIndex()

Method Detail

makeRuleSearchState

public IndexMatcher makeRuleSearchState(SimpleMode mode)

setDita

public void setDita(boolean dita)

Enable DITA-OT optimization

Parameters:

dita -

setMinRules

public void setMinRules(int minRules)

explain

public void explain(ExpressionPresenter out)

size

public int size()

optimize

public void optimize()

Optimize the indicies - in fact it is essential this is executed, to form up the internal indexes.

maybeIndexable

public com.saxonica.ee.pattern.preconditions.ComparisonPredicateIndex.IndexAndRHS maybeIndexable(AncestorQualifiedPattern p)

Determine whether this AncestorQualifiedPattern can be indexed and if so return a suitable index/value pair Note that only the base pattern is used in the index; the upper pattern is associated with the rule and is attached to the rule list members - in this way flat and ancestor-qualified patterns that share the same base (e.g. a/*[@z='a'] and *[@z='b']) can share the same index.

Parameters:

p - the pattern to test

Returns:

an indexation instance, or null if it cannot be indexed

maybeDITAIndexable

public com.saxonica.ee.pattern.preconditions.ComparisonPredicateIndex.IndexAndRHS maybeDITAIndexable(PatternWithPredicate p)

Determine whether this pattern can be indexed against the semantics of DITA-OT stylesheets and if so return a suitable indexation index/value pair. DITA-OT matches are of the form: ancestry?*[contains(@class,' tag ')] and the main pattern is converted to: *[tokenize(@class,'\s+')='tag'] The base, LHS and RHS of the index instance come from that rewriting.

Parameters:

p - the pattern to test

Returns:

an indexation instance, or null if it cannot be indexed

maybeDITAIndexable

public com.saxonica.ee.pattern.preconditions.ComparisonPredicateIndex.IndexAndRHS maybeDITAIndexable(AncestorQualifiedPattern p)

Determine whether this AncestorQualifiedPattern can be indexed against the semantics of DITA-OT stylesheets and if so return a suitable index/value pair

Parameters:

p - the pattern to test

Returns:

an indexation instance, or null if it cannot be indexed

add

public void add(Rule r)

Add a rule to a simple index if possible

Parameters:

r - the template rule to be checked and indexed if possible