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

public Class PredictionContextCache

extends Object
Class Inheritance
Imports
java.util.HashMap, .Map

Used to cache PredictionContext objects. Its used for the shared context cash associated with contexts in DFA states. This cache can be used for both lexers and parsers.
Author
Sam Harwell

Nested and Inner Type Summary

Modifier and TypeClass and Description
protected static class
protected static class

Field Summary

Modifier and TypeField and Description
private final Map<PredictionContextCache.PredictionContextAndInt, PredictionContext>
private final Map<PredictionContext, PredictionContext>
private final boolean
private final Map<PredictionContextCache.IdentityCommutativePredictionContextOperands, PredictionContext>
public static final PredictionContextCache

Constructor Summary

AccessConstructor and Description
public
private
PredictionContextCache(boolean enableCache)

Method Summary

Modifier and TypeMethod and Description
public PredictionContext
public PredictionContext
getChild(PredictionContext context, int invokingState)

public PredictionContext
Inherited from java.lang.Object:
cloneequalsfinalizegetClasshashCodenotifynotifyAlltoStringwaitwaitwait

Field Detail

childContextsback to summary
private final Map<PredictionContextCache.PredictionContextAndInt, PredictionContext> childContexts
contextsback to summary
private final Map<PredictionContext, PredictionContext> contexts
enableCacheback to summary
private final boolean enableCache
joinContextsback to summary
private final Map<PredictionContextCache.IdentityCommutativePredictionContextOperands, PredictionContext> joinContexts
UNCACHEDback to summary
public static final PredictionContextCache UNCACHED

Constructor Detail

PredictionContextCacheback to summary
public PredictionContextCache()
PredictionContextCacheback to summary
private PredictionContextCache(boolean enableCache)

Method Detail

getAsCachedback to summary
public PredictionContext getAsCached(PredictionContext context)
getChildback to summary
public PredictionContext getChild(PredictionContext context, int invokingState)
joinback to summary
public PredictionContext join(PredictionContext x, PredictionContext y)
org.antlr.v4.runtime.atn back to summary

protected final Class PredictionContextCache.IdentityCommutativePredictionContextOperands

extends Object
Class Inheritance
  • java.lang.Object
  • org.antlr.v4.runtime.atn.PredictionContextCache.IdentityCommutativePredictionContextOperands

Field Summary

Modifier and TypeField and Description
private final PredictionContext
x

private final PredictionContext
y

Constructor Summary

AccessConstructor and Description
public

Method Summary

Modifier and TypeMethod and Description
public 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 PredictionContext
getX()

public PredictionContext
getY()

public int
hashCode()

Overrides java.lang.Object.hashCode.

Returns a hash code value for the object.
Inherited from java.lang.Object:
clonefinalizegetClassnotifynotifyAlltoStringwaitwaitwait

Field Detail

xback to summary
private final PredictionContext x
yback to summary
private final PredictionContext y

Constructor Detail

IdentityCommutativePredictionContextOperandsback to summary
public IdentityCommutativePredictionContextOperands(PredictionContext x, PredictionContext y)

Method Detail

equalsback to summary
public 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
getXback to summary
public PredictionContext getX()
getYback to summary
public PredictionContext getY()
hashCodeback to summary
public 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
org.antlr.v4.runtime.atn back to summary

protected final Class PredictionContextCache.PredictionContextAndInt

extends Object
Class Inheritance
  • java.lang.Object
  • org.antlr.v4.runtime.atn.PredictionContextCache.PredictionContextAndInt

Field Summary

Modifier and TypeField and Description
private final PredictionContext
private final int

Constructor Summary

AccessConstructor and Description
public

Method Summary

Modifier and TypeMethod and Description
public 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 int
hashCode()

Overrides java.lang.Object.hashCode.

Returns a hash code value for the object.
Inherited from java.lang.Object:
clonefinalizegetClassnotifynotifyAlltoStringwaitwaitwait

Field Detail

objback to summary
private final PredictionContext obj
valueback to summary
private final int value

Constructor Detail

PredictionContextAndIntback to summary
public PredictionContextAndInt(PredictionContext obj, int value)

Method Detail

equalsback to summary
public 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
hashCodeback to summary
public 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