public UnicodeMatcher lookupMatcher(int ch) {
        UnicodeSet retVal = null;
        if (ch == 0xffff) {
            retVal = fCachedSetLookup;
            fCachedSetLookup = null;
        }
        return retVal;
    }
public UnicodeMatcher lookupMatcher ( int ch ) { UnicodeSet retVal = null ; if ( ch == 0xffff ) { retVal = fCachedSetLookup ; fCachedSetLookup = null ; } return retVal ; }
and we just need to remember what set to return between these two calls.