ANTLR 4 Runtime 4.13.1 · org.antlr.v4.runtime.atn.PredictionContext

Modifier and Type	Field and Description
public final int	cachedHashCode Stores the computed hash code of this `PredictionContext`.
public static final int	EMPTY_RETURN_STATE Represents `$` in an array in full context mode, when `$` doesn't mean wildcard: `$ + x = [$,x]`.
private static final AtomicInteger	globalNodeCount
public final int	id
private static final int	INITIAL_HASH

Access	Constructor and Description
protected	PredictionContext(int cachedHashCode)

Method Summary

Modifier and Type	Method and Description
protected static int	calculateEmptyHashCode()
protected static int	calculateHashCode(PredictionContext parent, int returnState)
protected static int	calculateHashCode(PredictionContext[] parents, int[] returnStates)
protected static void	combineCommonParents(PredictionContext[] parents) Make pass over all M `parents`; merge any `equals()` ones.
public abstract boolean	equals(Object the reference object with which to compare. obj) Overrides java.lang.Object.equals. Indicates whether some other object is "equal to" this one.
public static PredictionContext	fromRuleContext(ATN atn, RuleContext outerContext) Convert a `RuleContext` tree to a `PredictionContext` graph.
public static List<PredictionContext>	getAllContextNodes(PredictionContext context)
public static void	getAllContextNodes_(PredictionContext context, List<PredictionContext> nodes, Map<PredictionContext, PredictionContext> visited)
public static PredictionContext	getCachedContext(PredictionContext context, PredictionContextCache contextCache, IdentityHashMap<PredictionContext, PredictionContext> visited)
public abstract PredictionContext	getParent(int index)
public abstract int	getReturnState(int index)
public boolean	hasEmptyPath()
public final int	hashCode() Overrides java.lang.Object.hashCode. Returns a hash code value for the object.
public boolean	isEmpty() This means only the `EmptyPredictionContext#Instance` (wildcard?
public static PredictionContext	merge(PredictionContext a, PredictionContext b, boolean rootIsWildcard, DoubleKeyMap<PredictionContext, PredictionContext, PredictionContext> mergeCache)
public static PredictionContext	mergeArrays(ArrayPredictionContext a, ArrayPredictionContext b, boolean rootIsWildcard, DoubleKeyMap<PredictionContext, PredictionContext, PredictionContext> mergeCache) Merge two `ArrayPredictionContext` instances.
public static PredictionContext	mergeRoot(SingletonPredictionContext the first `SingletonPredictionContext` a, SingletonPredictionContext the second `SingletonPredictionContext` b, boolean `true` if this is a local-context merge, otherwise false to indicate a full-context merge rootIsWildcard) Handle case where at least one of `a` or `b` is `EmptyPredictionContext#Instance`.
public static PredictionContext	mergeSingletons(SingletonPredictionContext the first `SingletonPredictionContext` a, SingletonPredictionContext the second `SingletonPredictionContext` b, boolean `true` if this is a local-context merge, otherwise false to indicate a full-context merge rootIsWildcard, DoubleKeyMap<PredictionContext, PredictionContext, PredictionContext> mergeCache) Merge two `SingletonPredictionContext` instances.
public abstract int	size()
public static String	toDOTString(PredictionContext context)
public String	toString(Recognizer<?, ?> recog)
public String[]	toStrings(Recognizer<?, ?> recognizer, int currentState)
public String[]	toStrings(Recognizer<?, ?> recognizer, PredictionContext stop, int currentState)

Inherited from java.lang.Object:: clone finalize getClass notify notifyAll toString wait wait wait

cachedHashCode	back to summary
public final int cachedHashCode Stores the computed hash code of this `PredictionContext`. The hash code is computed in parts to match the following reference algorithm. private int referenceHashCode() { int hash = `MurmurHash.initialize`(`INITIAL_HASH`); for (int i = 0; i < `size()`; i++) { hash = `MurmurHash.update`(hash, `getParent`(i)); } for (int i = 0; i < `size()`; i++) { hash = `MurmurHash.update`(hash, `getReturnState`(i)); } hash = `MurmurHash.finish`(hash, 2 * `size()`); return hash; }

EMPTY_RETURN_STATE	back to summary
public static final int EMPTY_RETURN_STATE Represents `$` in an array in full context mode, when `$` doesn't mean wildcard: `$ + x = [$,x]`. Here, `$` = `EMPTY_RETURN_STATE`.

globalNodeCount	back to summary
private static final AtomicInteger globalNodeCount

id	back to summary
public final int id

INITIAL_HASH	back to summary
private static final int INITIAL_HASH

PredictionContext	back to summary
protected PredictionContext(int cachedHashCode)

Method Detail

calculateEmptyHashCode	back to summary
protected static int calculateEmptyHashCode()

calculateHashCode	back to summary
protected static int calculateHashCode(PredictionContext parent, int returnState)

calculateHashCode	back to summary
protected static int calculateHashCode(PredictionContext[] parents, int[] returnStates)

combineCommonParents	back to summary
protected static void combineCommonParents(PredictionContext[] parents) Make pass over all M `parents`; merge any `equals()` ones.

equals back to summary

equals	back to summary
public abstract boolean equals(Object obj) Overrides java.lang.Object.equals. Doc from java.lang.Object.equals. Indicates whether some other object is "equal to" this one. The `equals` method implements an equivalence relation on non-null object references: It is reflexive: for any non-null reference value `x`, `x.equals(x)` should return `true`. It is symmetric: for any non-null reference values `x` and `y`, `x.equals(y)` should return `true` if and only if `y.equals(x)` returns `true`. It is transitive: for any non-null reference values `x`, `y`, and `z`, if `x.equals(y)` returns `true` and `y.equals(z)` returns `true`, then `x.equals(z)` should return `true`. It is consistent: for any non-null reference values `x` and `y`, multiple invocations of `x.equals(y)` consistently return `true` or consistently return `false`, provided no information used in `equals` comparisons on the objects is modified. For any non-null reference value `x`, `x.equals(null)` should return `false`. An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes. Parameters obj:Object the reference object with which to compare. Returns:boolean `true` if this object is the same as the obj argument; `false` otherwise. Annotations @Override

public abstract boolean equals(Object obj)

Overrides java.lang.Object.equals.

Doc from java.lang.Object.equals.

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

It is reflexive: for any non-null reference value x, x.equals(x) should return true.
It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters

obj:Object: the reference object with which to compare.

Returns:boolean

true if this object is the same as the obj argument; false otherwise.

Annotations

@Override

fromRuleContext	back to summary
public static PredictionContext fromRuleContext(ATN atn, RuleContext outerContext) Convert a `RuleContext` tree to a `PredictionContext` graph. Return `EmptyPredictionContext#Instance` if `outerContext` is empty or null.

getAllContextNodes	back to summary
public static List<PredictionContext> getAllContextNodes(PredictionContext context)

getAllContextNodes_	back to summary
public static void getAllContextNodes_(PredictionContext context, List<PredictionContext> nodes, Map<PredictionContext, PredictionContext> visited)

getCachedContext	back to summary
public static PredictionContext getCachedContext(PredictionContext context, PredictionContextCache contextCache, IdentityHashMap<PredictionContext, PredictionContext> visited)

getParent	back to summary
public abstract PredictionContext getParent(int index)

getReturnState	back to summary
public abstract int getReturnState(int index)

hasEmptyPath	back to summary
public boolean hasEmptyPath()

hashCode back to summary

hashCode	back to summary
public final int hashCode() Overrides java.lang.Object.hashCode. Doc from java.lang.Object.hashCode. Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by `java.util.HashMap`. The general contract of `hashCode` is: Whenever it is invoked on the same object more than once during an execution of a Java application, the `hashCode` method must consistently return the same integer, provided no information used in `equals` comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. If two objects are equal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce the same integer result. It is not required that if two objects are unequal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables. Returns:int a hash code value for this object. Annotations @Override

public final int hashCode()

Overrides java.lang.Object.hashCode.

Doc from java.lang.Object.hashCode.

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is:

Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

Returns:int

a hash code value for this object.

Annotations

@Override

isEmpty	back to summary
public boolean isEmpty() This means only the `EmptyPredictionContext#Instance` (wildcard? not sure) context is in set.

merge	back to summary
public static PredictionContext merge(PredictionContext a, PredictionContext b, boolean rootIsWildcard, DoubleKeyMap<PredictionContext, PredictionContext, PredictionContext> mergeCache)

mergeArrays back to summary

mergeArrays	back to summary
public static PredictionContext mergeArrays(ArrayPredictionContext a, ArrayPredictionContext b, boolean rootIsWildcard, DoubleKeyMap<PredictionContext, PredictionContext, PredictionContext> mergeCache) Merge two `ArrayPredictionContext` instances. Different tops, different parents. Shared top, same parents. Shared top, different parents. Shared top, all shared parents. Equal tops, merge parents and reduce top to `SingletonPredictionContext`.

public static PredictionContext mergeArrays(ArrayPredictionContext a, ArrayPredictionContext b, boolean rootIsWildcard, DoubleKeyMap<PredictionContext, PredictionContext, PredictionContext> mergeCache)

Merge two ArrayPredictionContext instances.

Different tops, different parents.

Shared top, same parents.

Shared top, different parents.

Shared top, all shared parents.

Equal tops, merge parents and reduce top to SingletonPredictionContext.

mergeRoot back to summary

mergeRoot	back to summary
public static PredictionContext mergeRoot(SingletonPredictionContext a, SingletonPredictionContext b, boolean rootIsWildcard) Handle case where at least one of `a` or `b` is `EmptyPredictionContext#Instance`. In the following diagrams, the symbol `$` is used to represent `EmptyPredictionContext#Instance`. Local-Context Merges These local-context merge operations are used when `rootIsWildcard` is true. `EmptyPredictionContext#Instance` is superset of any graph; return `EmptyPredictionContext#Instance`. `EmptyPredictionContext#Instance` and anything is `#EMPTY`, so merged parent is `#EMPTY`; return left graph. Special case of last merge if local context. Full-Context Merges These full-context merge operations are used when `rootIsWildcard` is false. Must keep all contexts; `EmptyPredictionContext#Instance` in array is a special value (and null parent). Parameters a:SingletonPredictionContext the first `SingletonPredictionContext` b:SingletonPredictionContext the second `SingletonPredictionContext` rootIsWildcard:boolean `true` if this is a local-context merge, otherwise false to indicate a full-context merge

public static PredictionContext mergeRoot(SingletonPredictionContext a, SingletonPredictionContext b, boolean rootIsWildcard)

Handle case where at least one of a or b is EmptyPredictionContext#Instance. In the following diagrams, the symbol $ is used to represent EmptyPredictionContext#Instance.

Local-Context Merges

These local-context merge operations are used when rootIsWildcard is true.

EmptyPredictionContext#Instance is superset of any graph; return EmptyPredictionContext#Instance.

EmptyPredictionContext#Instance and anything is #EMPTY, so merged parent is #EMPTY; return left graph.

Special case of last merge if local context.

Full-Context Merges

These full-context merge operations are used when rootIsWildcard is false.

Must keep all contexts; EmptyPredictionContext#Instance in array is a special value (and null parent).

Parameters

a:SingletonPredictionContext: the first SingletonPredictionContext
b:SingletonPredictionContext: the second SingletonPredictionContext
rootIsWildcard:boolean: true if this is a local-context merge, otherwise false to indicate a full-context merge

mergeSingletons back to summary

mergeSingletons	back to summary
public static PredictionContext mergeSingletons(SingletonPredictionContext a, SingletonPredictionContext b, boolean rootIsWildcard, DoubleKeyMap<PredictionContext, PredictionContext, PredictionContext> mergeCache) Merge two `SingletonPredictionContext` instances. Stack tops equal, parents merge is same; return left graph. Same stack top, parents differ; merge parents giving array node, then remainders of those graphs. A new root node is created to point to the merged parents. Different stack tops pointing to same parent. Make array node for the root where both element in the root point to the same (original) parent. Different stack tops pointing to different parents. Make array node for the root where each element points to the corresponding original parent. Parameters a:SingletonPredictionContext the first `SingletonPredictionContext` b:SingletonPredictionContext the second `SingletonPredictionContext` rootIsWildcard:boolean `true` if this is a local-context merge, otherwise false to indicate a full-context merge

public static PredictionContext mergeSingletons(SingletonPredictionContext a, SingletonPredictionContext b, boolean rootIsWildcard, DoubleKeyMap<PredictionContext, PredictionContext, PredictionContext> mergeCache)

Merge two SingletonPredictionContext instances.

Stack tops equal, parents merge is same; return left graph.

Same stack top, parents differ; merge parents giving array node, then remainders of those graphs. A new root node is created to point to the merged parents.

Different stack tops pointing to same parent. Make array node for the root where both element in the root point to the same (original) parent.

Different stack tops pointing to different parents. Make array node for the root where each element points to the corresponding original parent.

Parameters

a:SingletonPredictionContext: the first SingletonPredictionContext
b:SingletonPredictionContext: the second SingletonPredictionContext
rootIsWildcard:boolean: true if this is a local-context merge, otherwise false to indicate a full-context merge

size	back to summary
public abstract int size()

toDOTString	back to summary
public static String toDOTString(PredictionContext context)

toString	back to summary
public String toString(Recognizer<?, ?> recog)

toStrings	back to summary
public String[] toStrings(Recognizer<?, ?> recognizer, int currentState)

toStrings	back to summary
public String[] toStrings(Recognizer<?, ?> recognizer, PredictionContext stop, int currentState)

public abstract Class PredictionContext

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

Local-Context Merges

Full-Context Merges