src/main/java/com/basistech/tclre/Locale.java
public static UnicodeSet cclass(String cclassName, boolean casefold) throws RegexException {
        try {
            if (casefold) {
                return KNOWN_SETS_CI.get(cclassName);
            } else {
                return KNOWN_SETS_CS.get(cclassName);
            }
        } catch (ExecutionException e) {
            Throwables.propagateIfInstanceOf(e.getCause(), RegexException.class);
            throw new RegexRuntimeException(e.getCause());
        }
    }
public static UnicodeSet cclass(String cclassName, boolean casefold) throws RegexException {
        try {
            if (casefold) {
                return KNOWN_SETS_CI.get(cclassName);
            } else {
                return KNOWN_SETS_CS.get(cclassName);
            }
        } catch (ExecutionException e) {
            Throwables.propagateIfInstanceOf(e.getCause(), RegexException.class);
            throw new RegexRuntimeException(e.getCause());
        }
    }
Return a UnicodeSet for a character class name.
It appears that the names that TCL accepts are also acceptable to ICU.

@param cclassName class name
@param casefold whether to include casefolding
@return set