org.antlr.v4.runtime.atn

Class ATNConfigSet

java.lang.Object

org.antlr.v4.runtime.atn.ATNConfigSet

All Implemented Interfaces:

Iterable<ATNConfig>, Collection<ATNConfig>, Set<ATNConfig>

Direct Known Subclasses:

OrderedATNConfigSet

public class ATNConfigSet
extends Object
implements Set<ATNConfig>

Specialized Set<ATNConfig> that can track info about the set, with support for combining similar configurations using a graph-structured stack.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ATNConfigSet.AbstractConfigHashSet
static class	ATNConfigSet.ConfigEqualityComparator
static class	ATNConfigSet.ConfigHashSet The reason that we need this is because we don't want the hash map to use the standard hash code and equals.

Field Summary

Fields

Modifier and Type	Field and Description
ATNConfigSet.AbstractConfigHashSet	configLookup All configs but hashed by (s, i, _, pi) not including context.
ArrayList<ATNConfig>	configs Track the elements as they are added to the set; supports get(i)
protected BitSet	conflictingAlts Currently this is only used when we detect SLL conflict; this does not necessarily represent the ambiguous alternatives.
boolean	dipsIntoOuterContext
boolean	fullCtx Indicates that this configuration set is part of a full context LL prediction.
boolean	hasSemanticContext
protected boolean	readonly Indicates that the set of configurations is read-only.
int	uniqueAlt

Constructor Summary

Constructors

Constructor and Description
ATNConfigSet()
ATNConfigSet(ATNConfigSet old)
ATNConfigSet(boolean fullCtx)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	add(ATNConfig config)
boolean	add(ATNConfig config, DoubleKeyMap<PredictionContext,PredictionContext,PredictionContext> mergeCache) Adding a new config means merging contexts with existing configs for (s, i, pi, _), where s is the ATNConfig.state, i is the ATNConfig.alt, and pi is the ATNConfig.semanticContext.
boolean	addAll(Collection<? extends ATNConfig> coll)
void	clear()
boolean	contains(Object o)
boolean	containsAll(Collection<?> c)
boolean	containsFast(ATNConfig obj)
List<ATNConfig>	elements() Return a List holding list of configs
boolean	equals(Object o)
ATNConfig	get(int i)
BitSet	getAlts() Gets the complete set of represented alternatives for the configuration set.
List<SemanticContext>	getPredicates()
Set<ATNState>	getStates()
int	hashCode()
boolean	isEmpty()
boolean	isReadonly()
Iterator<ATNConfig>	iterator()
void	optimizeConfigs(ATNSimulator interpreter)
boolean	remove(Object o)
boolean	removeAll(Collection<?> c)
boolean	retainAll(Collection<?> c)
void	setReadonly(boolean readonly)
int	size()
ATNConfig[]	toArray()
<T> T[]	toArray(T[] a)
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

readonly

protected boolean readonly

Indicates that the set of configurations is read-only. Do not allow any code to manipulate the set; DFA states will point at the sets and they must not change. This does not protect the other fields; in particular, conflictingAlts is set after we've made this readonly.

configLookup

public ATNConfigSet.AbstractConfigHashSet configLookup

All configs but hashed by (s, i, _, pi) not including context. Wiped out when we go readonly as this set becomes a DFA state.

configs

public final ArrayList<ATNConfig> configs

Track the elements as they are added to the set; supports get(i)

uniqueAlt

public int uniqueAlt

conflictingAlts

protected BitSet conflictingAlts

Currently this is only used when we detect SLL conflict; this does not necessarily represent the ambiguous alternatives. In fact, I should also point out that this seems to include predicated alternatives that have predicates that evaluate to false. Computed in computeTargetState().

hasSemanticContext

public boolean hasSemanticContext

dipsIntoOuterContext

public boolean dipsIntoOuterContext

fullCtx

public final boolean fullCtx

Indicates that this configuration set is part of a full context LL prediction. It will be used to determine how to merge $. With SLL it's a wildcard whereas it is not for LL context merge.

Constructor Detail

ATNConfigSet

public ATNConfigSet(boolean fullCtx)

ATNConfigSet

public ATNConfigSet()

ATNConfigSet

public ATNConfigSet(ATNConfigSet old)

Method Detail

add

public boolean add(ATNConfig config)

Specified by:

add in interface Collection<ATNConfig>

Specified by:

add in interface Set<ATNConfig>

add

public boolean add(ATNConfig config,
          DoubleKeyMap<PredictionContext,PredictionContext,PredictionContext> mergeCache)

Adding a new config means merging contexts with existing configs for (s, i, pi, _), where s is the ATNConfig.state, i is the ATNConfig.alt, and pi is the ATNConfig.semanticContext. We use (s,i,pi) as key.

This method updates dipsIntoOuterContext and hasSemanticContext when necessary.

elements

public List<ATNConfig> elements()

Return a List holding list of configs

getStates

public Set<ATNState> getStates()

getAlts

public BitSet getAlts()

Gets the complete set of represented alternatives for the configuration set.

Returns:

the set of represented alternatives in this configuration set

Since:

4.3

getPredicates

public List<SemanticContext> getPredicates()

get

public ATNConfig get(int i)

optimizeConfigs

public void optimizeConfigs(ATNSimulator interpreter)

addAll

public boolean addAll(Collection<? extends ATNConfig> coll)

Specified by:

addAll in interface Collection<ATNConfig>

Specified by:

addAll in interface Set<ATNConfig>

equals

public boolean equals(Object o)

Specified by:

equals in interface Collection<ATNConfig>

Specified by:

equals in interface Set<ATNConfig>

Overrides:

equals in class Object

hashCode

public int hashCode()

Specified by:

hashCode in interface Collection<ATNConfig>

Specified by:

hashCode in interface Set<ATNConfig>

Overrides:

hashCode in class Object

size

public int size()

Specified by:

size in interface Collection<ATNConfig>

Specified by:

size in interface Set<ATNConfig>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection<ATNConfig>

Specified by:

isEmpty in interface Set<ATNConfig>

contains

public boolean contains(Object o)

Specified by:

contains in interface Collection<ATNConfig>

Specified by:

contains in interface Set<ATNConfig>

containsFast

public boolean containsFast(ATNConfig obj)

iterator

public Iterator<ATNConfig> iterator()

Specified by:

iterator in interface Iterable<ATNConfig>

Specified by:

iterator in interface Collection<ATNConfig>

Specified by:

iterator in interface Set<ATNConfig>

clear

public void clear()

Specified by:

clear in interface Collection<ATNConfig>

Specified by:

clear in interface Set<ATNConfig>

isReadonly

public boolean isReadonly()

setReadonly

public void setReadonly(boolean readonly)

toString

public String toString()

Overrides:

toString in class Object

toArray

public ATNConfig[] toArray()

Specified by:

toArray in interface Collection<ATNConfig>

Specified by:

toArray in interface Set<ATNConfig>

toArray

public <T> T[] toArray(T[] a)

Specified by:

toArray in interface Collection<ATNConfig>

Specified by:

toArray in interface Set<ATNConfig>

remove

public boolean remove(Object o)

Specified by:

remove in interface Collection<ATNConfig>

Specified by:

remove in interface Set<ATNConfig>

containsAll

public boolean containsAll(Collection<?> c)

Specified by:

containsAll in interface Collection<ATNConfig>

Specified by:

containsAll in interface Set<ATNConfig>

retainAll

public boolean retainAll(Collection<?> c)

Specified by:

retainAll in interface Collection<ATNConfig>

Specified by:

retainAll in interface Set<ATNConfig>

removeAll

public boolean removeAll(Collection<?> c)

Specified by:

removeAll in interface Collection<ATNConfig>

Specified by:

removeAll in interface Set<ATNConfig>