/**
* Caches and returns all unique tokens specified in a query.
*
* @param list token list
* @return token set
*/
private TokenSet unique(final TokenList list) {
// cache all query tokens in a set (duplicates are removed)
final TokenSet ts = new TokenSet();
switch (mode) {
case ALL:
case ANY:
for (final byte[] t : list) ts.add(t);
break;
case ALL_WORDS:
case ANY_WORD:
final FTLexer l = new FTLexer(ftt.opt);
for (final byte[] t : list) {
l.init(t);
while (l.hasNext()) ts.add(l.nextToken());
}
break;
case PHRASE:
final TokenBuilder tb = new TokenBuilder();
for (final byte[] t : list) tb.add(t).add(' ');
ts.add(tb.trim().finish());
}
return ts;
}