我想根据数字字段对搜索结果进行排序.
在下面的示例代码中,我想基于“年龄”字段进行排序.
我从使用以下答案开始:
[How to sort IntPont or LongPoint field in Lucene 6
但是它确实基于SCORE进行排序.年龄仍然没有上升.
和
[Sorting search result in Lucene based on a numeric field
我在搜索功能中将SortField.Type.SCORE更改为SortField.Type.LONG.
但是我得到:
unexpected docvalues type NONE for field ‘age’ (expected=NUMERIC)
这是我的代码:
public class TestLongPointSort {
public static void main(String[] args) throws Exception {
String indexPath = "/tmp/testSort";
Analyzer standardAnalyzer = new StandardAnalyzer();
Directory indexDir = FSDirectory.open(Paths.get(indexPath));
IndexWriterConfig iwc = new IndexWriterConfig(standardAnalyzer);
iwc.setOpenMode(IndexWriterConfig.OpenMode.CREATE_OR_APPEND);
IndexWriter masterIndex = new IndexWriter(indexDir, iwc);
Document doc = new Document();
String name = "bob";
doc.add(new TextField("name", name, Field.Store.YES));
doc.add(new SortedDocValuesField("name", new BytesRef(name)));
doc.add(new SortedNumericDocValuesField("age", 20L));
doc.add(new StoredField("age", 20L));
long ts = System.currentTimeMillis();
doc.add(new SortedNumericDocValuesField("ts", ts));
doc.add(new StoredField("ts", ts));
masterIndex.addDocument(doc);
Thread.sleep(1);
name = "max";
doc = new Document();
doc.add(new TextField("name", name, Field.Store.YES));
doc.add(new SortedDocValuesField("name", new BytesRef(name)));
doc.add(new SortedNumericDocValuesField("age", 19L));
doc.add(new StoredField("age", 19L));
ts = System.currentTimeMillis();
doc.add(new SortedNumericDocValuesField("ts", ts));
doc.add(new StoredField("ts", ts));
masterIndex.addDocument(doc);
Thread.sleep(1);
name = "jim";
doc = new Document();
doc.add(new TextField("name", name, Field.Store.YES));
doc.add(new SortedDocValuesField("name", new BytesRef(name)));
doc.add(new SortedNumericDocValuesField("age", 21L));
doc.add(new StoredField("age", 21L));
ts = System.currentTimeMillis();
doc.add(new SortedNumericDocValuesField("ts", ts));
doc.add(new StoredField("ts", ts));
masterIndex.addDocument(doc);
masterIndex.commit();
masterIndex.close();
IndexReader reader = DirectoryReader.open(FSDirectory.open(Paths.get(indexPath)));
IndexSearcher searcher = new IndexSearcher(reader);
Analyzer analyzer = new KeywordAnalyzer();
QueryParser queryParser = new QueryParser("message", analyzer);
Sort sort;
TopDocs docs;
sort = new Sort(new SortField("name", SortField.Type.STRING));
docs = searcher.search(new MatchAllDocsQuery(), 100, sort);
System.out.println("Sorted by name");
for (ScoreDoc scoreDoc : docs.scoreDocs) {
Document doc2 = searcher.doc(scoreDoc.doc);
System.out.println("Name:" + doc2.get("name") + " ; age:" + doc2.get("age") + " ; ts:" + doc2.get("ts"));
}
//docs = searcher.search(new MatchAllDocsQuery(), 100, new Sort(new SortField("age", SortField.Type.SCORE, true)));
docs = searcher.search(new MatchAllDocsQuery(), 100, new Sort(new SortField("age", SortField.Type.LONG, true)));
System.out.println("Sorted by age");
for (ScoreDoc scoreDoc : docs.scoreDocs) {
Document doc2 = searcher.doc(scoreDoc.doc);
System.out.println("Name:" + doc2.get("name") + " ; age:" + doc2.get("age") + " ; ts:" + doc2.get("ts"));
}
reader.close();
}
}
如我们所见,对STRING进行排序很好,但是我不知道如何对数字(LONG)进行排序.
排序数字字段的正确方法是什么?
谢谢
解决方法:
要使用SortedNumericDocValuesField对搜索结果进行排序,您需要使用SortedNumericSortField
:
Sort sort = new Sort(new SortedNumericSortField("age", SortField.Type.LONG, true));
TopDocs docs = searcher.search(new MatchAllDocsQuery(), 100, sort);