public void consume(CharStream input) {
		int curChar = input.LA(1);
		if ( curChar=='\n' ) {
			line++;
			charPositionInLine=0;
		}
		else {
			charPositionInLine++;
		}
		input.consume();
	}
Get the text matched so far for the current token.
runtime/Java/src/org/antlr/v4/runtime/atn/LexerATNSimulator.java