DefaultErrorStrategy class
This is the default implementation of ANTLRErrorStrategy
used for
error reporting and recovery in ANTLR parsers.
- Implemented types
- Implementers
Constructors
Properties
- errorRecoveryMode ↔ bool
-
Indicates whether the error strategy is currently "recovering from an
error". This is used to suppress reporting multiple error messages while
attempting to recover from a detected syntax error.
getter/setter pair
- hashCode → int
-
The hash code for this object.
no setterinherited
- lastErrorIndex ↔ int
-
The index into the input stream where the last error occurred.
This is used to prevent infinite loops where an error is found
but no token is consumed during recovery...another error is found,
ad nauseum. This is a failsafe mechanism to guarantee that at least
one token/tree node is consumed for two errors.
getter/setter pair
- lastErrorStates ↔ IntervalSet?
-
getter/setter pair
- nextTokensContext ↔ ParserRuleContext?
-
This field is used to propagate information about the lookahead following
the previous match. Since prediction prefers completing the current rule
to error recovery efforts, error reporting may occur later than the
original point where it was discoverable. The original context is used to
compute the true expected sets as though the reporting occurred as early
as possible.
getter/setter pair
- nextTokensState ↔ int?
-
@see #nextTokensContext
getter/setter pair
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
beginErrorCondition(
Parser recognizer) → void - This method is called to enter error recovery mode when a recognition exception is reported.
-
consumeUntil(
Parser recognizer, IntervalSet set) → void - Consume tokens until one matches the given token set. */
-
endErrorCondition(
Parser recognizer) → void - This method is called to leave error recovery mode after recovering from a recognition exception.
-
escapeWSAndQuote(
String s) → String -
getErrorRecoverySet(
Parser recognizer) → IntervalSet -
getExpectedTokens(
Parser recognizer) → IntervalSet -
getMissingSymbol(
Parser recognizer) → Token - Conjure up a missing token during error recovery.
-
getSymbolText(
Token symbol) → String? -
getSymbolType(
Token symbol) → int -
getTokenErrorDisplay(
Token? t) → String - 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.
-
inErrorRecoveryMode(
Parser recognizer) → bool -
{@inheritDoc}
override
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
recover(
Parser recognizer, RecognitionException< IntStream> e) → void -
{@inheritDoc}
override
-
recoverInline(
Parser recognizer) → Token -
{@inheritDoc}
override
-
reportError(
Parser recognizer, RecognitionException< IntStream> e) → void -
{@inheritDoc}
override
-
reportFailedPredicate(
Parser recognizer, FailedPredicateException e) → void - This is called by {@link #reportError} when the exception is a FailedPredicateException.
-
reportInputMismatch(
Parser recognizer, InputMismatchException e) → void - This is called by {@link #reportError} when the exception is an InputMismatchException.
-
reportMatch(
Parser recognizer) → void -
{@inheritDoc}
override
-
reportMissingToken(
Parser recognizer) → void -
This method is called to report a syntax error which requires the
insertion of a missing token into the input stream. At the time this
method is called, the missing token has not yet been inserted. When this
method returns,
recognizer
is in error recovery mode. -
reportNoViableAlternative(
Parser recognizer, NoViableAltException e) → void - This is called by {@link #reportError} when the exception is a NoViableAltException.
-
reportUnwantedToken(
Parser recognizer) → void -
This method is called to report a syntax error which requires the removal
of a token from the input stream. At the time this method is called, the
erroneous symbol is current {@code LT(1)} symbol and has not yet been
removed from the input stream. When this method returns,
recognizer
is in error recovery mode. -
reset(
Parser recognizer) → void -
{@inheritDoc}
override
-
singleTokenDeletion(
Parser recognizer) → Token? -
This method implements the single-token deletion inline error recovery
strategy. It is called by {@link #recoverInline} to attempt to recover
from mismatched input. If this method returns null, the parser and error
handler state will not have changed. If this method returns non-null,
recognizer
will not be in error recovery mode since the returned token was a successful match. -
singleTokenInsertion(
Parser recognizer) → bool -
This method implements the single-token insertion inline error recovery
strategy. It is called by {@link #recoverInline} if the single-token
deletion strategy fails to recover from the mismatched input. If this
method returns
true
,recognizer
will be in error recovery mode. -
sync(
Parser recognizer) → void -
The default implementation of {@link ANTLRErrorStrategy#sync} makes sure
that the current lookahead symbol is consistent with what were expecting
at this point in the ATN. You can call this anytime but ANTLR only
generates code to check before subrules/loops and each iteration.
override
-
toString(
) → String -
A string representation of this object.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited