Regex nodes SingleA, NotSingleA, SingleU and NotSingleU always report the
hitEnd() to be true when match/find failed, even the "end" has not been reached.

The cases below show the problem.

        // SingleA
p = Pattern.compile("^a", Pattern.CASE_INSENSITIVE);
m = p.matcher("bcd");
if (m.find() || m.hitEnd()) {
failCount++;
}

        // NotSingleA
p = Pattern.compile("^[^\u4e00]", Pattern.CASE_INSENSITIVE);
m = p.matcher("\u4e00cd");
if (m.find() || m.hitEnd()) {
failCount++;
}

        // SingleU
p = Pattern.compile("^\u4e00", Pattern.CASE_INSENSITIVE |Pattern.UNICODE_CASE);
m = p.matcher("abc");
if (m.find() || m.hitEnd()) {
failCount++;
}

        // NotSingleU
p = Pattern.compile("^[^\u03b2]", Pattern.CASE_INSENSITIVE |Pattern.UNICODE_CASE);
m = p.matcher("\u0392bc");
if (m.find() || m.hitEnd()) {
failCount++;
}