@Override
    public int read(char[] c) {
        return read(c, 0, c.length);
    }
Used by DocumentsWriter to implemented a StringReader that can be reset to a
new string; we use this when tokenizing the string value from a Field.
stroom-index/stroom-index-lucene553/src/test/java/stroom/index/lucene553/analyser/ReusableStringReader.java