assertEquals("", normalizeText(" ", 100, -1, 2, false));
        assertEquals("", normalizeText("  ", 100, -1, 2, false));
        assertEquals("", normalizeText("\t", 100, -1, 2, false));
        assertEquals("", normalizeText("\t\t", 100, -1, 2, false));
        assertEquals("", normalizeText("\t \t", 100, -1, 2, false));
        assertEquals("123 abc", normalizeText(" 123 abc ", 100, -1, 2, false));

        public TextNormalizeContext spaceChars(final int[] spaceChars) {
            this.spaceChars = spaceChars;
            return this;
        }
    }

    public static TextNormalizeContext normalizeText(final Reader reader) {
        return new TextNormalizeContext(reader);
    }

    private static boolean isLastSpaceChar(final StringBuilder buf) {
        if (buf.length() == 0) {
            return false;