final RegularExpression regexPattern = makePatternXerces(pattern, flags);
if (regexPattern == null)
return s;
else {
Match m = new Match();
if(regexPattern.matches(s,m)){
String result = "";
while(regexPattern.matches(s,m)){
int numberOfGroups = m.getNumberOfGroups();
if(numberOfGroups>0){
String interReplacement = new String(replacement);