org.antlr.v4.runtime

Class Recognizer<Symbol,ATNInterpreter extends ATNSimulator>

java.lang.Object

org.antlr.v4.runtime.Recognizer<Symbol,ATNInterpreter>

Direct Known Subclasses:

Lexer, Parser

public abstract class Recognizer<Symbol,ATNInterpreter extends ATNSimulator>
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
protected ATNInterpreter	_interp
static int	EOF

Constructor Summary

Constructors

Constructor and Description
Recognizer()

Method Summary

Methods

Modifier and Type	Method and Description
void	action(RuleContext _localctx, int ruleIndex, int actionIndex)
void	addErrorListener(ANTLRErrorListener<? super Symbol> listener)
ATN	getATN() Get the ATN used by the recognizer for prediction.
String	getErrorHeader(RecognitionException e) What is the error header, normally line/character position information?
ANTLRErrorListener<? super Symbol>	getErrorListenerDispatch()
List<? extends ANTLRErrorListener<? super Symbol>>	getErrorListeners()
abstract String	getGrammarFileName() For debugging and other purposes, might want the grammar name.
abstract IntStream	getInputStream()
ATNInterpreter	getInterpreter() Get the ATN interpreter used by the recognizer for prediction.
ParseInfo	getParseInfo() If profiling during the parse/lex, this will return DecisionInfo records for each decision in recognizer in a ParseInfo object.
Map<String,Integer>	getRuleIndexMap() Get a map from rule names to rule indexes.
abstract String[]	getRuleNames()
String	getSerializedATN() If this recognizer was generated, it will have a serialized ATN representation of the grammar.
int	getState()
String	getTokenErrorDisplay(Token t) Deprecated. This method is not called by the ANTLR 4 Runtime. Specific implementations of ANTLRErrorStrategy may provide a similar feature when necessary. For example, see DefaultErrorStrategy.getTokenErrorDisplay(org.antlr.v4.runtime.Token).
abstract String[]	getTokenNames() Deprecated. Use getVocabulary() instead.
int	getTokenType(String tokenName)
Map<String,Integer>	getTokenTypeMap() Get a map from token names to token types.
Vocabulary	getVocabulary() Get the vocabulary used by the recognizer.
boolean	precpred(RuleContext localctx, int precedence)
void	removeErrorListener(ANTLRErrorListener<? super Symbol> listener)
void	removeErrorListeners()
boolean	sempred(RuleContext _localctx, int ruleIndex, int actionIndex)
void	setInterpreter(ATNInterpreter interpreter) Set the ATN interpreter used by the recognizer for prediction.
void	setState(int atnState) Indicate that the recognizer has changed internal state that is consistent with the ATN state passed in.

Methods inherited from class java.lang.Object

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

Field Detail

EOF

public static final int EOF

See Also:

Constant Field Values

_interp

protected ATNInterpreter extends ATNSimulator _interp

Constructor Detail

Recognizer

public Recognizer()

Method Detail

getTokenNames

@Deprecated
public abstract String[] getTokenNames()

Deprecated. Use getVocabulary() instead.

Used to print out token names like ID during debugging and error reporting. The generated parsers implement a method that overrides this to point to their String[] tokenNames.

getRuleNames

public abstract String[] getRuleNames()

getVocabulary

@NotNull
public Vocabulary getVocabulary()

Get the vocabulary used by the recognizer.

Returns:

A Vocabulary instance providing information about the vocabulary used by the grammar.

getTokenTypeMap

@NotNull
public Map<String,Integer> getTokenTypeMap()

Get a map from token names to token types.

Used for XPath and tree pattern compilation.

getRuleIndexMap

@NotNull
public Map<String,Integer> getRuleIndexMap()

Get a map from rule names to rule indexes.

Used for XPath and tree pattern compilation.

getTokenType

public int getTokenType(String tokenName)

getSerializedATN

@NotNull
public String getSerializedATN()

If this recognizer was generated, it will have a serialized ATN representation of the grammar.

For interpreters, we don't know their serialized ATN despite having created the interpreter from it.

getGrammarFileName

public abstract String getGrammarFileName()

For debugging and other purposes, might want the grammar name. Have ANTLR generate an implementation for this method.

getATN

@NotNull
public ATN getATN()

Get the ATN used by the recognizer for prediction.

Returns:

The ATN used by the recognizer for prediction.

getInterpreter

@NotNull
public ATNInterpreter getInterpreter()

Get the ATN interpreter used by the recognizer for prediction.

Returns:

The ATN interpreter used by the recognizer for prediction.

getParseInfo

public ParseInfo getParseInfo()

If profiling during the parse/lex, this will return DecisionInfo records for each decision in recognizer in a ParseInfo object.

Since:

4.3

setInterpreter

public void setInterpreter(@NotNull
                  ATNInterpreter interpreter)

Set the ATN interpreter used by the recognizer for prediction.

Parameters:

interpreter - The ATN interpreter used by the recognizer for prediction.

getErrorHeader

@NotNull
public String getErrorHeader(@NotNull
                            RecognitionException e)

What is the error header, normally line/character position information?

getTokenErrorDisplay

@Deprecated
public String getTokenErrorDisplay(Token t)

Deprecated. This method is not called by the ANTLR 4 Runtime. Specific implementations of ANTLRErrorStrategy may provide a similar feature when necessary. For example, see DefaultErrorStrategy.getTokenErrorDisplay(org.antlr.v4.runtime.Token).

How should a token be displayed in an error message? The default is to display just the text, but during development you might want to have a lot of information spit out. Override in that case to use t.toString() (which, for CommonToken, dumps everything about the token). This is better than forcing you to override a method in your token objects because you don't have to go modify your lexer so that it creates a new Java type.

addErrorListener

public void addErrorListener(@NotNull
                    ANTLRErrorListener<? super Symbol> listener)

Throws:

NullPointerException - if listener is null.

removeErrorListener

public void removeErrorListener(@NotNull
                       ANTLRErrorListener<? super Symbol> listener)

removeErrorListeners

public void removeErrorListeners()

getErrorListeners

@NotNull
public List<? extends ANTLRErrorListener<? super Symbol>> getErrorListeners()

getErrorListenerDispatch

public ANTLRErrorListener<? super Symbol> getErrorListenerDispatch()

sempred

public boolean sempred(@Nullable
              RuleContext _localctx,
              int ruleIndex,
              int actionIndex)

precpred

public boolean precpred(@Nullable
               RuleContext localctx,
               int precedence)

action

public void action(@Nullable
          RuleContext _localctx,
          int ruleIndex,
          int actionIndex)

getState

public final int getState()

setState

public final void setState(int atnState)

Indicate that the recognizer has changed internal state that is consistent with the ATN state passed in. This way we always know where we are in the ATN as the parser goes along. The rule context objects form a stack that lets us see the stack of invoking rules. Combine this and we have complete ATN configuration information.

getInputStream

public abstract IntStream getInputStream()