DecisionEventInfo (ANTLR 4 Runtime 4.13.2 API)

java.lang.Object
- org.antlr.v4.runtime.atn.DecisionEventInfo

Direct Known Subclasses:

AmbiguityInfo, ContextSensitivityInfo, ErrorInfo, LookaheadEventInfo, PredicateEvalInfo
```
public class DecisionEventInfo
extends Object
```
This is the base class for gathering detailed information about prediction events which occur during parsing. Note that we could record the parser call stack at the time this event occurred but in the presence of left recursive rules, the stack is kind of meaningless. It's better to look at the individual configurations for their individual stacks. Of course that is a PredictionContext object not a parse tree node and so it does not have information about the extent (start...stop) of the various subtrees. Examining the stack tops of all configurations provide the return states for the rule invocations. From there you can get the enclosing rule.

Since:

4.3

Field Summary

Fields
Modifier and Type	Field	Description
`ATNConfigSet`	`configs`	The configuration set containing additional information relevant to the prediction state when the current event occurred, or `null` if no additional information is relevant or available.
`int`	`decision`	The invoked decision number which this event is related to.
`boolean`	`fullCtx`	`true` if the current event occurred during LL prediction; otherwise, `false` if the input occurred during SLL prediction.
`TokenStream`	`input`	The input token stream which is being parsed.
`int`	`startIndex`	The token index in the input stream at which the current prediction was originally invoked.
`int`	`stopIndex`	The token index in the input stream at which the current event occurred.

Constructor Summary

Constructors
Constructor	Description
`DecisionEventInfo(int decision, ATNConfigSet configs, TokenStream input, int startIndex, int stopIndex, boolean fullCtx)`

Method Summary
- Methods inherited from class java.lang.Object
  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - decision
```
public final int decision
```
    The invoked decision number which this event is related to.
    
    See Also:
    
    ATN.decisionToState
  - configs
```
public final ATNConfigSet configs
```
    The configuration set containing additional information relevant to the prediction state when the current event occurred, or null if no additional information is relevant or available.
  - input
```
public final TokenStream input
```
    The input token stream which is being parsed.
  - startIndex
```
public final int startIndex
```
    The token index in the input stream at which the current prediction was originally invoked.
  - stopIndex
```
public final int stopIndex
```
    The token index in the input stream at which the current event occurred.
  - fullCtx
```
public final boolean fullCtx
```
    true if the current event occurred during LL prediction; otherwise, false if the input occurred during SLL prediction.
- Constructor Detail
  - DecisionEventInfo
```
public DecisionEventInfo(int decision,
                         ATNConfigSet configs,
                         TokenStream input,
                         int startIndex,
                         int stopIndex,
                         boolean fullCtx)
```