Top Description Inners Fields Constructors Methods
org.antlr.v4.runtime.atn

public Class ATNConfigSet

extends Object
implements Set<ATNConfig>
Class Inheritance
All Implemented Interfaces
java.util.Set, java.util.Collection, java.lang.Iterable
Known Direct Subclasses
org.antlr.v4.runtime.atn.OrderedATNConfigSet
Imports
org.antlr.v4.runtime.misc.AbstractEqualityComparator, .Array2DHashSet, .DoubleKeyMap, java.util.ArrayList, .BitSet, .Collection, .HashSet, .Iterator, .List, .Set

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

Nested and Inner Type Summary

Modifier and TypeClass and Description
public abstract static class
public static class
public 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

Modifier and TypeField and Description
private int
public ATNConfigSet.AbstractConfigHashSet
configLookup

All configs but hashed by (s, i, _, pi) not including context.

public final 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.

public boolean
public final boolean
fullCtx

Indicates that this configuration set is part of a full context LL prediction.

public boolean
protected boolean
readonly

Indicates that the set of configurations is read-only.

public int

Constructor Summary

AccessConstructor and Description
public
ATNConfigSet(boolean fullCtx)

public
public

Method Summary

Modifier and TypeMethod and Description
public boolean
add(ATNConfig
element to be added to this set
config
)

Implements java.util.Set.add.

Adds the specified element to this set if it is not already present (optional operation).
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.

public boolean
addAll(Collection<? extends ATNConfig>
collection containing elements to be added to this set
coll
)

Implements java.util.Set.addAll.

Adds all of the elements in the specified collection to this set if they're not already present (optional operation).
public void
clear()

Implements java.util.Set.clear.

Removes all of the elements from this set (optional operation).
public boolean
contains(Object
element whose presence in this set is to be tested
o
)

Implements java.util.Set.contains.

Returns true if this set contains the specified element.
public boolean
containsAll(Collection<?>
collection to be checked for containment in this set
c
)

Implements java.util.Set.containsAll.

Returns true if this set contains all of the elements of the specified collection.
public boolean
public List<ATNConfig>
elements()

Return a List holding list of configs

public boolean
equals(Object
object to be compared for equality with this set
o
)

Overrides java.lang.Object.equals.

Implements java.util.Set.equals.

Compares the specified object with this set for equality.
public ATNConfig
get(int i)

public BitSet

Returns:

the set of represented alternatives in this configuration set
getAlts
()

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

public List<SemanticContext>
public Set<ATNState>
public int
hashCode()

Overrides java.lang.Object.hashCode.

Implements java.util.Set.hashCode.

Returns the hash code value for this set.
public boolean
isEmpty()

Implements java.util.Set.isEmpty.

Returns true if this set contains no elements.
public boolean
public Iterator<ATNConfig>
iterator()

Implements java.util.Set.iterator.

Returns an iterator over the elements in this set.
public void
public boolean
remove(Object
object to be removed from this set, if present
o
)

Implements java.util.Set.remove.

Removes the specified element from this set if it is present (optional operation).
public boolean
removeAll(Collection<?>
collection containing elements to be removed from this set
c
)

Implements java.util.Set.removeAll.

Removes from this set all of its elements that are contained in the specified collection (optional operation).
public boolean
retainAll(Collection<?>
collection containing elements to be retained in this set
c
)

Implements java.util.Set.retainAll.

Retains only the elements in this set that are contained in the specified collection (optional operation).
public void
setReadonly(boolean readonly)

public int
size()

Implements java.util.Set.size.

Returns the number of elements in this set (its cardinality).
public ATNConfig[]
toArray()

Implements java.util.Set.toArray.

Returns an array containing all of the elements in this set.
public <T> T[]
toArray(T[]
the array into which the elements of this set are to be stored, if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose.
a
)

Implements java.util.Set.toArray.

Returns an array containing all of the elements in this set; the runtime type of the returned array is that of the specified array.
public String
toString()

Overrides java.lang.Object.toString.

Returns a string representation of the object.
Inherited from java.lang.Object:
clonefinalizegetClassnotifynotifyAllwaitwaitwait

Field Detail

cachedHashCodeback to summary
private int cachedHashCode
configLookupback to summary
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.

configsback to summary
public final ArrayList<ATNConfig> configs

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

conflictingAltsback to summary
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().

dipsIntoOuterContextback to summary
public boolean dipsIntoOuterContext
fullCtxback to summary
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.

hasSemanticContextback to summary
public boolean hasSemanticContext
readonlyback to summary
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.

uniqueAltback to summary
public int uniqueAlt

Constructor Detail

ATNConfigSetback to summary
public ATNConfigSet(boolean fullCtx)
ATNConfigSetback to summary
public ATNConfigSet()
ATNConfigSetback to summary
public ATNConfigSet(ATNConfigSet old)

Method Detail

addback to summary
public boolean add(ATNConfig config)

Implements java.util.Set.add.

Doc from java.util.Set.add.

Adds the specified element to this set if it is not already present (optional operation). More formally, adds the specified element e to this set if the set contains no element e2 such that Objects.equals(e, e2). If this set already contains the element, the call leaves the set unchanged and returns false. In combination with the restriction on constructors, this ensures that sets never contain duplicate elements.

The stipulation above does not imply that sets must accept all elements; sets may refuse to add any particular element, including null, and throw an exception, as described in the specification for Collection.add. Individual set implementations should clearly document any restrictions on the elements that they may contain.

Parameters
config:ATNConfig

element to be added to this set

Returns:boolean

true if this set did not already contain the specified element

Annotations
@Override
addback to summary
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.

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

Implements java.util.Set.addAll.

Doc from java.util.Set.addAll.

Adds all of the elements in the specified collection to this set if they're not already present (optional operation). If the specified collection is also a set, the addAll operation effectively modifies this set so that its value is the union of the two sets. The behavior of this operation is undefined if the specified collection is modified while the operation is in progress.

Parameters
coll:Collection<? extends ATNConfig>

collection containing elements to be added to this set

Returns:boolean

true if this set changed as a result of the call

Annotations
@Override
clearback to summary
public void clear()

Implements java.util.Set.clear.

Doc from java.util.Set.clear.

Removes all of the elements from this set (optional operation). The set will be empty after this call returns.

Annotations
@Override
containsback to summary
public boolean contains(Object o)

Implements java.util.Set.contains.

Doc from java.util.Set.contains.

Returns true if this set contains the specified element. More formally, returns true if and only if this set contains an element e such that Objects.equals(o, e).

Parameters
o:Object

element whose presence in this set is to be tested

Returns:boolean

true if this set contains the specified element

Annotations
@Override
containsAllback to summary
public boolean containsAll(Collection<?> c)

Implements java.util.Set.containsAll.

Doc from java.util.Set.containsAll.

Returns true if this set contains all of the elements of the specified collection. If the specified collection is also a set, this method returns true if it is a subset of this set.

Parameters
c:Collection<?>

collection to be checked for containment in this set

Returns:boolean

true if this set contains all of the elements of the specified collection

Annotations
@Override
containsFastback to summary
public boolean containsFast(ATNConfig obj)
elementsback to summary
public List<ATNConfig> elements()

Return a List holding list of configs

equalsback to summary
public boolean equals(Object o)

Overrides java.lang.Object.equals.

Implements java.util.Set.equals.

Doc from java.util.Set.equals.

Compares the specified object with this set for equality. Returns true if the specified object is also a set, the two sets have the same size, and every member of the specified set is contained in this set (or equivalently, every member of this set is contained in the specified set). This definition ensures that the equals method works properly across different implementations of the set interface.

Parameters
o:Object

object to be compared for equality with this set

Returns:boolean

true if the specified object is equal to this set

Annotations
@Override
getback to summary
public ATNConfig get(int i)
getAltsback to summary
public BitSet getAlts()

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

Returns:BitSet

the set of represented alternatives in this configuration set

Since
4.3
getPredicatesback to summary
public List<SemanticContext> getPredicates()
getStatesback to summary
public Set<ATNState> getStates()
hashCodeback to summary
public int hashCode()

Overrides java.lang.Object.hashCode.

Implements java.util.Set.hashCode.

Doc from java.util.Set.hashCode.

Returns the hash code value for this set. The hash code of a set is defined to be the sum of the hash codes of the elements in the set, where the hash code of a null element is defined to be zero. This ensures that s1.equals(s2) implies that s1.hashCode()==s2.hashCode() for any two sets s1 and s2, as required by the general contract of Object#hashCode.

Returns:int

the hash code value for this set

Annotations
@Override
isEmptyback to summary
public boolean isEmpty()

Implements java.util.Set.isEmpty.

Doc from java.util.Set.isEmpty.

Returns true if this set contains no elements.

Returns:boolean

true if this set contains no elements

Annotations
@Override
isReadonlyback to summary
public boolean isReadonly()
iteratorback to summary
public Iterator<ATNConfig> iterator()

Implements java.util.Set.iterator.

Doc from java.util.Set.iterator.

Returns an iterator over the elements in this set. The elements are returned in no particular order (unless this set is an instance of some class that provides a guarantee).

Returns:Iterator<ATNConfig>

an iterator over the elements in this set

Annotations
@Override
optimizeConfigsback to summary
public void optimizeConfigs(ATNSimulator interpreter)
removeback to summary
public boolean remove(Object o)

Implements java.util.Set.remove.

Doc from java.util.Set.remove.

Removes the specified element from this set if it is present (optional operation). More formally, removes an element e such that Objects.equals(o, e), if this set contains such an element. Returns true if this set contained the element (or equivalently, if this set changed as a result of the call). (This set will not contain the element once the call returns.)

Parameters
o:Object

object to be removed from this set, if present

Returns:boolean

true if this set contained the specified element

Annotations
@Override
removeAllback to summary
public boolean removeAll(Collection<?> c)

Implements java.util.Set.removeAll.

Doc from java.util.Set.removeAll.

Removes from this set all of its elements that are contained in the specified collection (optional operation). If the specified collection is also a set, this operation effectively modifies this set so that its value is the asymmetric set difference of the two sets.

Parameters
c:Collection<?>

collection containing elements to be removed from this set

Returns:boolean

true if this set changed as a result of the call

Annotations
@Override
retainAllback to summary
public boolean retainAll(Collection<?> c)

Implements java.util.Set.retainAll.

Doc from java.util.Set.retainAll.

Retains only the elements in this set that are contained in the specified collection (optional operation). In other words, removes from this set all of its elements that are not contained in the specified collection. If the specified collection is also a set, this operation effectively modifies this set so that its value is the intersection of the two sets.

Parameters
c:Collection<?>

collection containing elements to be retained in this set

Returns:boolean

true if this set changed as a result of the call

Annotations
@Override
setReadonlyback to summary
public void setReadonly(boolean readonly)
sizeback to summary
public int size()

Implements java.util.Set.size.

Doc from java.util.Set.size.

Returns the number of elements in this set (its cardinality). If this set contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.

Returns:int

the number of elements in this set (its cardinality)

Annotations
@Override
toArrayback to summary
public ATNConfig[] toArray()

Implements java.util.Set.toArray.

Doc from java.util.Set.toArray.

Returns an array containing all of the elements in this set. If this set makes any guarantees as to what order its elements are returned by its iterator, this method must return the elements in the same order.

The returned array will be "safe" in that no references to it are maintained by this set. (In other words, this method must allocate a new array even if this set is backed by an array). The caller is thus free to modify the returned array.

This method acts as bridge between array-based and collection-based APIs.

Returns:ATNConfig[]

an array containing all the elements in this set

Annotations
@Override
toArrayback to summary
public <T> T[] toArray(T[] a)

Implements java.util.Set.toArray.

Doc from java.util.Set.toArray.

Returns an array containing all of the elements in this set; the runtime type of the returned array is that of the specified array. If the set fits in the specified array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the specified array and the size of this set.

If this set fits in the specified array with room to spare (i.e., the array has more elements than this set), the element in the array immediately following the end of the set is set to null. (This is useful in determining the length of this set only if the caller knows that this set does not contain any null elements.)

If this set makes any guarantees as to what order its elements are returned by its iterator, this method must return the elements in the same order.

Like the toArray() method, this method acts as bridge between array-based and collection-based APIs. Further, this method allows precise control over the runtime type of the output array, and may, under certain circumstances, be used to save allocation costs.

Suppose x is a set known to contain only strings. The following code can be used to dump the set into a newly allocated array of String:

    String[] y = x.toArray(new String[0]);
Note that toArray(new Object[0]) is identical in function to toArray().
Parameters
<T>

Doc from java.util.Collection.toArray. the component type of the array to contain the collection

a:T[]

the array into which the elements of this set are to be stored, if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose.

Returns:T[]

an array containing all the elements in this set

Annotations
@Override
toStringback to summary
public String toString()

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object.

Returns:String

a string representation of the object

Annotations
@Override
org.antlr.v4.runtime.atn back to summary

public abstract Class ATNConfigSet.AbstractConfigHashSet

extends Array2DHashSet<ATNConfig>
Class Inheritance
Known Direct Subclasses
org.antlr.v4.runtime.atn.OrderedATNConfigSet.LexerConfigHashSet, org.antlr.v4.runtime.atn.ATNConfigSet.ConfigHashSet

Field Summary

Inherited from org.antlr.v4.runtime.misc.Array2DHashSet:
bucketscomparatorcurrentPrimeINITAL_BUCKET_CAPACITYINITAL_CAPACITYinitialBucketCapacityinitialCapacityLOAD_FACTORnthreshold

Constructor Summary

AccessConstructor and Description
public
public
AbstractConfigHashSet(AbstractEqualityComparator<? super ATNConfig> comparator, int initialCapacity, int initialBucketCapacity)

Method Summary

Modifier and TypeMethod and Description
protected final ATNConfig
asElementType(Object
the object to try and cast to the element type of the set
o
)

Overrides org.antlr.v4.runtime.misc.Array2DHashSet.asElementType.

Return o as an instance of the element type T.
protected final ATNConfig[]
createBucket(int
the length of the array to return
capacity
)

Overrides org.antlr.v4.runtime.misc.Array2DHashSet.createBucket.

Return an array of T with length capacity.
protected final ATNConfig[][]
createBuckets(int
the length of the array to return
capacity
)

Overrides org.antlr.v4.runtime.misc.Array2DHashSet.createBuckets.

Return an array of T[] with length capacity.
Inherited from org.antlr.v4.runtime.misc.Array2DHashSet:
addaddAllclearcontainscontainsAllcontainsFastequalsexpandgetgetBucketgetOrAddgetOrAddImplhashCodeisEmptyiteratorremoveremoveAllremoveFastretainAllsizetoArraytoArraytoStringtoTableString

Constructor Detail

AbstractConfigHashSetback to summary
public AbstractConfigHashSet(AbstractEqualityComparator<? super ATNConfig> comparator)
AbstractConfigHashSetback to summary
public AbstractConfigHashSet(AbstractEqualityComparator<? super ATNConfig> comparator, int initialCapacity, int initialBucketCapacity)

Method Detail

asElementTypeback to summary
protected final ATNConfig asElementType(Object o)

Overrides org.antlr.v4.runtime.misc.Array2DHashSet.asElementType.

Doc from org.antlr.v4.runtime.misc.Array2DHashSet.asElementType.

Return o as an instance of the element type T. If o is non-null but known to not be an instance of T, this method returns null. The base implementation does not perform any type checks; override this method to provide strong type checks for the contains and remove methods to ensure the arguments to the EqualityComparator for the set always have the expected types.

Parameters
o:Object

the object to try and cast to the element type of the set

Returns:ATNConfig

o if it could be an instance of T, otherwise null.

Annotations
@Override
createBucketback to summary
protected final ATNConfig[] createBucket(int capacity)

Overrides org.antlr.v4.runtime.misc.Array2DHashSet.createBucket.

Doc from org.antlr.v4.runtime.misc.Array2DHashSet.createBucket.

Return an array of T with length capacity.

Parameters
capacity:int

the length of the array to return

Returns:ATNConfig[]

the newly constructed array

Annotations
@Override
createBucketsback to summary
protected final ATNConfig[][] createBuckets(int capacity)

Overrides org.antlr.v4.runtime.misc.Array2DHashSet.createBuckets.

Doc from org.antlr.v4.runtime.misc.Array2DHashSet.createBuckets.

Return an array of T[] with length capacity.

Parameters
capacity:int

the length of the array to return

Returns:ATNConfig[][]

the newly constructed array

Annotations
@Override
org.antlr.v4.runtime.atn back to summary

public final Class ATNConfigSet.ConfigEqualityComparator

extends AbstractEqualityComparator<ATNConfig>
Class Inheritance

Field Summary

Modifier and TypeField and Description
public static final ATNConfigSet.ConfigEqualityComparator

Constructor Summary

AccessConstructor and Description
private

Method Summary

Modifier and TypeMethod and Description
public boolean
equals(ATNConfig
The first object to compare.
a
,
ATNConfig
The second object to compare.
b
)

Implements org.antlr.v4.runtime.misc.EqualityComparator.equals.

This method tests if two objects are equal.
public int
hashCode(ATNConfig
The object.
o
)

Implements org.antlr.v4.runtime.misc.EqualityComparator.hashCode.

This method returns a hash code for the specified object.

Field Detail

INSTANCEback to summary
public static final ATNConfigSet.ConfigEqualityComparator INSTANCE

Constructor Detail

ConfigEqualityComparatorback to summary
private ConfigEqualityComparator()

Method Detail

equalsback to summary
public boolean equals(ATNConfig a, ATNConfig b)

Implements org.antlr.v4.runtime.misc.EqualityComparator.equals.

Doc from org.antlr.v4.runtime.misc.EqualityComparator.equals.

This method tests if two objects are equal.

Parameters
a:ATNConfig

The first object to compare.

b:ATNConfig

The second object to compare.

Returns:boolean

true if a equals b, otherwise false.

Annotations
@Override
hashCodeback to summary
public int hashCode(ATNConfig o)

Implements org.antlr.v4.runtime.misc.EqualityComparator.hashCode.

Doc from org.antlr.v4.runtime.misc.EqualityComparator.hashCode.

This method returns a hash code for the specified object.

Parameters
o:ATNConfig

The object.

Returns:int

The hash code for obj.

Annotations
@Override
org.antlr.v4.runtime.atn back to summary

public Class ATNConfigSet.ConfigHashSet

extends AbstractConfigHashSet
Class Inheritance

The reason that we need this is because we don't want the hash map to use the standard hash code and equals. We need all configurations with the same (s,i,_,semctx) to be equal. Unfortunately, this key effectively doubles the number of objects associated with ATNConfigs. The other solution is to use a hash table that lets us specify the equals/hashcode operation.

Constructor Summary

AccessConstructor and Description
public

Method Summary

Inherited from org.antlr.v4.runtime.atn.ATNConfigSet.AbstractConfigHashSet:
asElementTypecreateBucketcreateBuckets

Constructor Detail

ConfigHashSetback to summary
public ConfigHashSet()