private void consumePatternLetters() {
        final int letter = consumeChar();
        int repetitions = 1;
        while (peek() == letter) {
            consumeChar();
            repetitions += 1;
        }
        processPatternLetter(letter, repetitions);
    }
Creates a new pattern read for processing the given string.
@param sequence String with the pattern to process.
@param visitor Visitor to call for each encountered token of the pattern.
primefaces/src/main/java/org/primefaces/convert/PatternReader.java