如何在Lucene中按长字段排序

Question

//create
Document doc = new Document();
//get value from JDBC ResultSet
doc.add(new LongDocValuesField("LastContactTime", rs.getLong("LastContactTime")));
//....
//Search
Sort sort = new Sort(new SortField("LastContactTime",
                    SortField.Type.LONG, false));
TopDocs rs = scher.search(query, total, sort);

The results are not sorted correctly,Why? I'm using Lucene4.0

Answer 1

LongDocValuesField is somewhat different in nature from a LongField .

It looks like (according to: http://www.searchworkings.org/blog/-/blogs/377217 ) you may be able to sort on them simply by calling setUseIndexValues, like:

SortField field = new SortField("LastContactTime",
                SortField.Type.LONG, false);
field.setUseIndexValues(true);
Sort sort = new Sort(sort);