Lucene.net范围查询+高亮 [英] Lucene.net range queries + highlighting
问题描述
还有一个Lucene.net问题由一个极端的新手吧。
Yet another Lucene.net question by an extreme newbie to it.
这时候，我发现了一个有趣的问题，使用一个包含范围的查询和使用突出。
This time, I have found an interesting issue with using a query that contains a range and using highlighting.
我是从内存中写入这一点，所以请原谅任何语法错误。
I am writing this from memory, so please forgive any syntax errors.
我有这样一个假设Lucene索引：
I have a hypothetical Lucene index of this:
---------------------------------------------------------
| date | text |
---------------------------------------------------------
| 1317809124 | a crazy block of text |
---------------------------------------------------------
| 1317809284 | programmers are crazy |
---------------------------------------------------------
** date is a unix timestamp
...和它们已被从这个添加到索引
... and they have been added to the index via this:
Lucene.Net.Documents.Document doc = new Lucene.Net.Documents.Document();
doc.Add(new Lucene.Net.Documents.Field("text", "some block of text", Lucene.Net.Documents.Field.Store.YES, Lucene.Net.Documents.Field.Index.ANALYZED, Lucene.Net.Documents.Field.TermVector.WITH_POSITIONS_OFFSETS));
doc.Add(new Lucene.Net.Documents.Field("date", "some unix timestamp", Lucene.Net.Documents.Field.Store.YES, Lucene.Net.Documents.Field.Index.NOT_ANALYZED));
这是我如何查询Lucene的：
This is how I am querying Lucene:
Lucene.Net.Analysis.Standard.StandardAnalyzer analyzer = new Lucene.Net.Analysis.Standard.StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_29);
Lucene.Net.Search.IndexSearcher searcher = new Lucene.Net.Search.IndexSearcher(Lucene.Net.Store.FSDirectory.Open(_headlinesDirectory), true);
Lucene.Net.QueryParsers.QueryParser parser = new Lucene.Net.QueryParsers.QueryParser(Lucene.Net.Util.Version.LUCENE_29, "text", analyzer);
Lucene.Net.Search.Query query = parser.Parse(queryPhrase);
Lucene.Net.Search.Hits hits = searcher.Search(query);
// code highlighting
Lucene.Net.Highlight.Formatter formatter = new Lucene.Net.Highlight.SimpleHTMLFormatter("<span style=\"background:yellow;\">","</span>");
Lucene.Net.Highlight.SimpleFragmenter fragmenter = new Lucene.Net.Highlight.SimpleFragmenter(50);
Lucene.Net.Highlight.QueryScorer scorer = new Lucene.Net.Highlight.QueryScorer(query);
Lucene.Net.Highlight.Highlighter highlighter = new Lucene.Net.Highlight.Highlighter(formatter, scorer);
highlighter.SetTextFragmenter(fragmenter);
for (int i = 0; i < hits.Length(); i++)
{
Lucene.Net.Documents.Document doc = hits.Doc(i);
Lucene.Net.Analysis.TokenStream stream = analyzer.TokenStream("", new StringReader(doc.Get("text")));
string highlightedText = highlighter.GetBestFragments(stream, doc.Get("text"), 1, "...");
Console.WriteLine("--> " + highlightedText);
}
下面是我的查询的例子：
Here is an example of my query:
crazy AND date:[1286273266 TO 32503680000]
在此查询，发现所有的结果疯狂，但不输出任何突出显示文本。
When this is queried, it finds all the results for "crazy" but does not output any highlighted text.
在该日期范围被删除，您只需要查询的术语：
When the date range is removed and you simply query the term:
crazy
...这个时候凸显正常工作。
... this time highlighting works properly.
有什么我做错了在我的实现，我应该寻找一个新的实现，或者这是一个已知问题，可能周围的工作。
Is there something I am doing wrong in my implementation, should I be looking at a new implementation, or is this a known issue with potentially a work around.
感谢您提前stackeroverflow'ers：）
Thank you in advance stackeroverflow'ers :)
- 编辑 -
我已经实现从LB的建议（顺便说一句惊人！）。我仍然不知道为什么这个工程，我认为Lucene是完整的巫术或编程巫术，但它确实和我很高兴：）
I have implemented the suggestions from LB (amazing btw!). I still have no idea why this works as I think Lucene is complete voodoo or programming witchcraft, but it does and I am happy :).
有关完整，这里是修改code：
For completeness, here is the modified code:
Lucene.Net.Analysis.Standard.StandardAnalyzer analyzer = new Lucene.Net.Analysis.Standard.StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_29);
Lucene.Net.Search.IndexSearcher searcher = new Lucene.Net.Search.IndexSearcher(Lucene.Net.Store.FSDirectory.Open(_headlinesDirectory), true);
Lucene.Net.QueryParsers.QueryParser parser = new Lucene.Net.QueryParsers.QueryParser(Lucene.Net.Util.Version.LUCENE_29, "text", analyzer);
// new line here
parser.SetMultiTermRewriteMethod(Lucene.Net.Search.MultiTermQuery.SCORING_BOOLEAN_QUERY_REWRITE);
Lucene.Net.Search.Query query = parser.Parse(queryPhrase);
// new line here
Lucene.Net.Search.Query query2 = query.Rewrite(searcher.GetIndexReader());
Lucene.Net.Search.Hits hits = searcher.Search(query);
// code highlighting
Lucene.Net.Highlight.Formatter formatter = new Lucene.Net.Highlight.SimpleHTMLFormatter("<span style=\"background:yellow;\">","</span>");
Lucene.Net.Highlight.SimpleFragmenter fragmenter = new Lucene.Net.Highlight.SimpleFragmenter(50);
// changed to use query2
Lucene.Net.Highlight.QueryScorer scorer = new Lucene.Net.Highlight.QueryScorer(query2);
Lucene.Net.Highlight.Highlighter highlighter = new Lucene.Net.Highlight.Highlighter(formatter, scorer);
highlighter.SetTextFragmenter(fragmenter);
for (int i = 0; i < hits.Length(); i++)
{
Lucene.Net.Documents.Document doc = hits.Doc(i);
Lucene.Net.Analysis.TokenStream stream = analyzer.TokenStream("", new StringReader(doc.Get("text")));
string highlightedText = highlighter.GetBestFragments(stream, doc.Get("text"), 1, "...");
Console.WriteLine("--> " + highlightedText);
}
如果你能，让我知道，如果我已经准确地执行这些建议。
If you could, let me know if I have implemented the suggestions accurately.
推荐答案
首先调用的QueryParser的
First invoke QueryParser's
SetMultiTermRewriteMethod（MultiTermQuery.SCORING_BOOLEAN_QUERY_REWRITE）
方法，然后创建一个新的查询，
method, then create a new query as
Query newQuery = query.Rewrite(indexReader);
现在你可以使用newQuery进行搜索。
Now you can use "newQuery" to make your searches.
这篇关于Lucene.net范围查询+高亮的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
