com.github.fge.grappa.matchers.join

Class JoinMatcher

java.lang.Object

com.github.fge.grappa.misc.ImmutableGraphNode<Matcher>

com.github.fge.grappa.matchers.base.AbstractMatcher

com.github.fge.grappa.matchers.base.CustomDefaultLabelMatcher<JoinMatcher>

com.github.fge.grappa.matchers.join.JoinMatcher

All Implemented Interfaces:

Matcher, GraphNode<Matcher>, Rule, Cloneable

Direct Known Subclasses:

BoundedBothJoinMatcher, BoundedDownJoinMatcher, BoundedUpJoinMatcher, ExactMatchesJoinMatcher

public abstract class JoinMatcher
extends CustomDefaultLabelMatcher<JoinMatcher>

A joining matcher

Such a matcher has two submatchers: a "joined" matcher and a "joining" matcher.

This matcher will run cycles through both of these; the first will be a run of the "joined" matcher, subsequent cycles will be ("joining", "joined").

Therefore:

• one cycle is joined;
• two cycles is joined, joining, joined;
• etc etc.

This matcher will correctly reset the index to the last successful match; for instance, if the match sequence is joined, joining, joined, joining and two cycles are enough, it will reset the index to before the last joining so that subsequent matchers can proceed from there.

It is forbidden for the "joining" matcher to match an empty sequence. Unfortunately, due to current limitations, this can only be detected at runtime.

This matcher is not built directly; its build is initiated by a JoinMatcherBootstrap. Example:

     Rule threeDigitsExactly()
     {
         return join(digit()).using('.').times(3);
     }
 

See Also:

JoinMatcherBootstrap

Field Summary

Fields

Modifier and Type	Field and Description
protected Matcher	joined
protected Matcher	joining

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	JoinMatcher(Rule joined, Rule joining)

Method Summary

Methods

Modifier and Type	Method and Description
protected abstract boolean	enoughCycles(int cycles)
MatcherType	getType() Returns the type of this matcher
<V> boolean	match(MatcherContext<V> context) Tries a match on the given MatcherContext.
protected <V> boolean	matchCycle(MatcherContext<V> context, int beforeCycle)
protected abstract boolean	runAgain(int cycles)

Methods inherited from class com.github.fge.grappa.matchers.base.CustomDefaultLabelMatcher

getLabel, hasCustomLabel

Methods inherited from class com.github.fge.grappa.matchers.base.AbstractMatcher

getSubContext, label, toString

Methods inherited from class com.github.fge.grappa.misc.ImmutableGraphNode

getChildren

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.github.fge.grappa.misc.GraphNode

getChildren

Field Detail

joined

protected final Matcher joined

joining

protected final Matcher joining

Constructor Detail

JoinMatcher

protected JoinMatcher(Rule joined,
           Rule joining)

Method Detail

getType

public final MatcherType getType()

Description copied from interface: Matcher

Returns the type of this matcher

Returns:

the type

See Also:

MatcherType

match

public final <V> boolean match(MatcherContext<V> context)

Tries a match on the given MatcherContext.

Parameters:

context - the MatcherContext

Returns:

true if the match was successful

runAgain

protected abstract boolean runAgain(int cycles)

enoughCycles

protected abstract boolean enoughCycles(int cycles)

matchCycle

protected final <V> boolean matchCycle(MatcherContext<V> context,
                     int beforeCycle)