private static String[] groupTokens(Analyzer analyzer, String input) throws IOException {
if (Resources.debug) {
Resources.LOGGER.debug("TokenParser:" + input);
Resources.LOGGER.debug("Analyzer:" + analyzer.getClass());
}
TokenStream tokenStream = analyzer.tokenStream("input", input);
OffsetAttribute offsetAttribute = tokenStream.addAttribute(OffsetAttribute.class);
PositionIncrementAttribute positionIncrementAttribute =
tokenStream.addAttribute(PositionIncrementAttribute.class);
CharTermAttribute charTermAttribute = tokenStream.addAttribute(CharTermAttribute.class);
TypeAttribute typeAttribute = tokenStream.addAttribute(TypeAttribute.class);
tokenStream.reset();
int position = 0;
List<TermInfo> infos = new ArrayList<TermInfo>();
while (tokenStream.incrementToken()) {
int increment = positionIncrementAttribute.getPositionIncrement();
if (increment > 0) {
position = position + increment;
if (Resources.debug) {
Resources.LOGGER.debug(position + ":");
}
}
int startOffset = offsetAttribute.startOffset();
int endOffset = offsetAttribute.endOffset();
String term = charTermAttribute.toString();
TermInfo info = new TermInfo();
info.setStart(startOffset);
info.setEnd(endOffset);
infos.add(info);
if (Resources.debug) {
Resources.LOGGER.debug(
"["
+ term
+ "]"
+ ":("
+ startOffset
+ "-->"
+ endOffset
+ "):"
+ typeAttribute.type());
}
}
tokenStream.end();
tokenStream.close();
Stack<TermInfo> tiStack = groupTokenInfos(infos);
List<String> terms = new ArrayList<String>();
while (!tiStack.isEmpty()) {
TermInfo termInfo = tiStack.pop();
if (termInfo.getEnd() <= input.length() && termInfo.getStart() >= 1) {
String term = input.substring(termInfo.getStart(), termInfo.getEnd());
terms.add(term);
}
}
return terms.toArray(new String[] {});
}
private static Stack<TermInfo> groupTokenInfos(List<TermInfo> infos) {
List<TermInfo> tis = new ArrayList<TermInfo>();
for (TermInfo info : infos) {
Integer len = info.getEnd() - info.getStart();
if (len == 1) {
tis.add(info);
}
}
Stack<TermInfo> tiStack = new Stack<TermInfo>();
for (Integer index = 0; index < tis.size(); index++) {
TermInfo info = tis.get(index);
TermInfo plus = info;
for (Integer next = index + 1; next < tis.size(); next++) {
TermInfo nextInfo = tis.get(next);
if (plus == null) {
plus = nextInfo;
continue;
}
plus = plus.plus(nextInfo);
if (plus != null) {
if (tiStack.isEmpty()) {
tiStack.push(plus);
} else if (!tiStack.contains(plus)) {
tiStack.push(plus);
}
}
}
}
return tiStack;
}