org.parboiled.matchers

Class OptionalMatcher

java.lang.Object

org.parboiled.trees.ImmutableGraphNode<Matcher>

org.parboiled.matchers.AbstractMatcher

org.parboiled.matchers.OptionalMatcher

All Implemented Interfaces:

Cloneable, Matcher, Rule, GraphNode<Matcher>

public class OptionalMatcher
extends AbstractMatcher

A Matcher that tries its submatcher once against the input and always succeeds.

Field Summary

Fields

Modifier and Type	Field and Description
Matcher	subMatcher

Constructor Summary

Constructors

Constructor and Description
OptionalMatcher(Rule subRule)

Method Summary

Methods

Modifier and Type	Method and Description
<R> R	accept(MatcherVisitor<R> visitor) Accepts the given matcher visitor.
T	defaultLabel(String defaultLabel)
String	getLabel()
boolean	hasCustomLabel()
boolean	match(MatcherContext context) Tries a match on the given MatcherContext.

Methods inherited from class org.parboiled.matchers.AbstractMatcher

areMismatchesMemoed, areSubnodesSuppressed, getSubContext, getTag, isNodeSkipped, isNodeSuppressed, label, memoMismatches, setTag, skipNode, suppressNode, suppressSubnodes, toString

Methods inherited from class org.parboiled.trees.ImmutableGraphNode

getChildren

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.parboiled.trees.GraphNode

getChildren

Field Detail

subMatcher

public final Matcher subMatcher

Constructor Detail

OptionalMatcher

public OptionalMatcher(Rule subRule)

Method Detail

match

public boolean match(MatcherContext context)

Description copied from interface: Matcher

Tries a match on the given MatcherContext.

Parameters:

context - the MatcherContext

Returns:

true if the match was successful

accept

public <R> R accept(MatcherVisitor<R> visitor)

Description copied from interface: Matcher

Accepts the given matcher visitor.

Parameters:

visitor - the visitor

Returns:

the value returned by the given visitor

getLabel

public String getLabel()

Specified by:

getLabel in interface Matcher

Overrides:

getLabel in class AbstractMatcher

Returns:

the label of the matcher (which is identical to the label of the Rule this matcher matches)

hasCustomLabel

public boolean hasCustomLabel()

Specified by:

hasCustomLabel in interface Matcher

Overrides:

hasCustomLabel in class AbstractMatcher

Returns:

true if this matcher has been assigned a custom label

defaultLabel

public T defaultLabel(String defaultLabel)