org.antlr.v4.runtime.atn

Class LookaheadEventInfo

java.lang.Object

org.antlr.v4.runtime.atn.DecisionEventInfo

org.antlr.v4.runtime.atn.LookaheadEventInfo

public class LookaheadEventInfo
extends DecisionEventInfo

This class represents profiling event information for tracking the lookahead depth required in order to make a prediction.

Since:

4.3

Field Summary

Fields

Modifier and Type	Field and Description
int	predictedAlt The alternative chosen by adaptivePredict(), not necessarily the outermost alt shown for a rule; left-recursive rules have user-level alts that differ from the rewritten rule with a (...) block and a (..)* loop.

Fields inherited from class org.antlr.v4.runtime.atn.DecisionEventInfo

decision, fullCtx, input, startIndex, state, stopIndex

Constructor Summary

Constructors

Constructor and Description
LookaheadEventInfo(int decision, SimulatorState state, int predictedAlt, TokenStream input, int startIndex, int stopIndex, boolean fullCtx) Constructs a new instance of the LookaheadEventInfo class with the specified detailed lookahead information.

Method Summary

Methods inherited from class java.lang.Object

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

Field Detail

predictedAlt

public final int predictedAlt

The alternative chosen by adaptivePredict(), not necessarily the outermost alt shown for a rule; left-recursive rules have user-level alts that differ from the rewritten rule with a (...) block and a (..)* loop.

Constructor Detail

LookaheadEventInfo

public LookaheadEventInfo(int decision,
                          @Nullable
                          SimulatorState state,
                          int predictedAlt,
                          @NotNull
                          TokenStream input,
                          int startIndex,
                          int stopIndex,
                          boolean fullCtx)

Constructs a new instance of the LookaheadEventInfo class with the specified detailed lookahead information.

Parameters:

decision - The decision number

state - The final simulator state containing the necessary information to determine the result of a prediction, or null if the final state is not available

input - The input token stream

startIndex - The start index for the current prediction

stopIndex - The index at which the prediction was finally made

fullCtx - true if the current lookahead is part of an LL prediction; otherwise, false if the current lookahead is part of an SLL prediction