char c = globPattern.charAt(i++);
switch (c) {
case '\\':
// escape special characters
if (i == globPattern.length()) {
throw new PatternSyntaxException("No character to escape",
globPattern, i - 1);
}
char next = globPattern.charAt(i++);
if (isGlobMeta(next) || isRegexMeta(next)) {
regex.append('\\');
}
regex.append(next);
break;
case '/':
if (isDos) {
regex.append("\\\\");
} else {
regex.append(c);
}
break;
case '[':
// don't match name separator in class
if (isDos) {
regex.append("[[^\\\\]&&[");
} else {
regex.append("[[^/]&&[");
}
if (next(globPattern, i) == '^') {
// escape the regex negation char if it appears
regex.append("\\^");
i++;
} else {
// negation
if (next(globPattern, i) == '!') {
regex.append('^');
i++;
}
// hyphen allowed at start
if (next(globPattern, i) == '-') {
regex.append('-');
i++;
}
}
boolean hasRangeStart = false;
char last = 0;
while (i < globPattern.length()) {
c = globPattern.charAt(i++);
if (c == ']') {
break;
}
if (c == '/' || (isDos && c == '\\')) {
throw new PatternSyntaxException("Explicit 'name separator' in class",
globPattern, i - 1);
}
// TBD: how to specify ']' in a class?
if (c == '\\' || c == '[' ||
c == '&' && next(globPattern, i) == '&') {
// escape '\', '[' or "&&" for regex class
regex.append('\\');
}
regex.append(c);
if (c == '-') {
if (!hasRangeStart) {
throw new PatternSyntaxException("Invalid range",
globPattern, i - 1);
}
if ((c = next(globPattern, i++)) == EOL || c == ']') {
break;
}
if (c < last) {
throw new PatternSyntaxException("Invalid range",
globPattern, i - 3);
}
regex.append(c);
hasRangeStart = false;
} else {
hasRangeStart = true;
last = c;
}
}
if (c != ']') {
throw new PatternSyntaxException("Missing ']", globPattern, i - 1);
}
regex.append("]]");
break;
case '{':
if (inGroup) {
throw new PatternSyntaxException("Cannot nest groups",
globPattern, i - 1);
}
regex.append("(?:(?:");
inGroup = true;
break;
case '}':
if (inGroup) {
regex.append("))");
inGroup = false;
} else {
regex.append('}');
}
break;
case ',':
if (inGroup) {
regex.append(")|(?:");
} else {
regex.append(',');
}
break;
case '*':
if (next(globPattern, i) == '*') {
// crosses directory boundaries
regex.append(".*");
i++;
} else {
// within directory boundary
if (isDos) {
regex.append("[^\\\\]*");
} else {
regex.append("[^/]*");
}
}
break;
case '?':
if (isDos) {
regex.append("[^\\\\]");
} else {
regex.append("[^/]");
}
break;
default:
if (isRegexMeta(c)) {
regex.append('\\');
}
regex.append(c);
}
}
if (inGroup) {
throw new PatternSyntaxException("Missing '}", globPattern, i - 1);
}
return regex.append('$').toString();
}