antlr
public abstract class InputBuffer extends Object
A dynamic array is used to buffer up all the input characters. Normally, "k" characters are stored in the buffer. More characters may be stored during guess mode (testing syntactic predicate), or when LT(i>k) is referenced. Consumption of characters is deferred. In other words, reading the next character is not done by conume(), but deferred until needed by LA or LT.
See Also: CharQueue
Field Summary | |
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protected int | markerOffset |
protected int | nMarkers |
protected int | numToConsume |
protected CharQueue | queue |
Constructor Summary | |
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InputBuffer() Create an input buffer |
Method Summary | |
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void | commit() This method updates the state of the input buffer so that
the text matched since the most recent mark() is no longer
held by the buffer. |
void | consume() Mark another character for deferred consumption |
abstract void | fill(int amount) Ensure that the input buffer is sufficiently full |
String | getLAChars() |
String | getMarkedChars() |
boolean | isMarked() |
char | LA(int i) Get a lookahead character |
int | mark() Return an integer marker that can be used to rewind the buffer to
its current state. |
void | reset() Reset the input buffer |
void | rewind(int mark) Rewind the character buffer to a marker. |
protected void | syncConsume() Sync up deferred consumption |
Parameters: mark Marker returned previously from mark()