com.saxonica.ee.pattern

Class PatternADJ

java.lang.Object

com.saxonica.ee.pattern.Adjunct

com.saxonica.ee.pattern.PatternADJ

Direct Known Subclasses:

AncestorQualifiedPatternADJ, BooleanExpressionPatternADJ, GeneralNodePatternADJ, GeneralPositionalPatternADJ, NodeSetPatternADJ, NodeTestPatternADJ, PatternThatSetsCurrentADJ, PatternWithPredicateADJ, SimplePositionalPatternADJ, VennPatternADJ

public class PatternADJ
extends Adjunct

Field Summary

Fields

Modifier and Type	Field and Description
Pattern	pattern

Constructor Summary

Constructors

Constructor and Description
PatternADJ(Pattern p)

Method Summary

Methods

Modifier and Type	Method and Description
Pattern	applyAxis(byte axis) Convert a pattern to apply to nodes along a given axis.
Pattern	copyLocationInfo(Pattern p) Copy location information from this Pattern onto another (new) Pattern
Pattern	evaluateAgainstBoolean(Expression e, PatternOptimizationEE patternOptimizationEE) Evaluate this pattern against an expression designated as 'true' in the execution context.
void	export(ExpressionPresenter out)
static Set<Expression>	getPatternPreconditions(PatternOptimizationEE patternOptimization, Pattern p) Get the preconditions for a pattern
Set<Expression>	getPreconditions(PatternOptimizationEE patternOptimization) Get the preconditions for a pattern
RetainedStaticContext	getRetainedStaticContext()
Pattern	optimizeForName(int i) Optimize a pattern with respect to a named node (element or attribute).
Pattern	optimizeForType(int type) Optimize a pattern with respect to a typed node.
Pattern	optimizePattern() Generic optimization of a pattern
static Pattern	optimizePattern(Pattern p)
Pattern	unify(PatternADJ source, RewriteContext rc)
Set<RewriteContext>	unifyingBindings(PatternADJ source, RewriteContext rc) Unify this expression against another expression

Methods inherited from class com.saxonica.ee.pattern.Adjunct

getExpressionAdjunct, getNodeTestAdjunct, getPatternAdjunct, index, processRewrites

Methods inherited from class java.lang.Object

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

Field Detail

pattern

public Pattern pattern

Constructor Detail

PatternADJ

public PatternADJ(Pattern p)

Method Detail

getRetainedStaticContext

public RetainedStaticContext getRetainedStaticContext()

optimizeForName

public Pattern optimizeForName(int i)

Optimize a pattern with respect to a named node (element or attribute). This is usually carried out on the base pattern, to determine if it will match the named node to be matched.

Parameters:

i - the fingerprint of the name of the node to be matched.

Returns:

null if it isn't for this named node, otherwise the pattern itself.

optimizeForType

public Pattern optimizeForType(int type)

Optimize a pattern with respect to a typed node. This is usually carried out on the base pattern, to determine if it will match the typed node to be matched.

Parameters:

type - the type of the node to be matched.

Returns:

null if it isn't for this type of node, otherwise the pattern itself.

optimizePattern

public Pattern optimizePattern()

Generic optimization of a pattern

Returns:

the optimization of the pattern

applyAxis

public Pattern applyAxis(byte axis)

Convert a pattern to apply to nodes along a given axis. If appropriate this normally returns a BooleanExpressionPattern containing a suitable FilterExpression

Parameters:

axis - The axis to mode this pattern to

Returns:

a pattern which matches the original pattern alonng a given axis.

evaluateAgainstBoolean

public Pattern evaluateAgainstBoolean(Expression e,
                             PatternOptimizationEE patternOptimizationEE)

Evaluate this pattern against an expression designated as 'true' in the execution context.

Parameters:

e - the expression assumed to be true.

patternOptimizationEE -

Returns:

a possibly modified pattern.

getPreconditions

public Set<Expression> getPreconditions(PatternOptimizationEE patternOptimization)

Get the preconditions for a pattern

Note that as a Pattern is a subclass of Expression, we need different named functions for each type.

Parameters:

patternOptimization - controls for the optimization

Returns:

a set of precondition expressions for this pattern

copyLocationInfo

public Pattern copyLocationInfo(Pattern p)

Copy location information from this Pattern onto another (new) Pattern

Parameters:

p - the Pattern to have location information added

Returns:

the input pattern.

optimizePattern

public static Pattern optimizePattern(Pattern p)

getPatternPreconditions

public static Set<Expression> getPatternPreconditions(PatternOptimizationEE patternOptimization,
                                      Pattern p)

Get the preconditions for a pattern

Note that as a Pattern is a subclass of Expression, we need different named functions for each type.

Parameters:

patternOptimization - controls for the optimization

p - the pattern to examine

Returns:

a set of precondition expressions for this pattern

unify

public Pattern unify(PatternADJ source,
            RewriteContext rc)

unifyingBindings

public Set<RewriteContext> unifyingBindings(PatternADJ source,
                                   RewriteContext rc)

Unify this expression against another expression

Parameters:

source - the expression to be unified against

rc - the evaluation context to use (which may be side-effected)

Returns:

a set of rewrite context bindings if it can unify, otherwise null

export

public void export(ExpressionPresenter out)