1. Apache Lucene
Full text search
Marcelo

2. What’s that?
 API created on 00’s
 Apache owns that
 Indexing
 Searching
 Available on Java, .NET, C++

3. Why is that so good?
 Enhance user experience
 More inteligent products
 Speed processing
 Relevance
 Efficient
 Suggestions

4. Indexing
 IndexWritter
1. Directory implementation
2. Analizer
 Create documents
 Add these document to IndexWritter
 Optimize (merge segments)
 Close writter

5. Indexing

6. Searching
 Directory
 IndexSearcher
 QueryParser
 Query(“my search”)
 TopDocs

7. Searching

8. How does that work?
 Inverted Index
 Term Normalization
1. Similar words (merge)
2. Stop words (remove)
3. +relevance –size on disk
Term Document Ids
And 1,2,3
Big 2,4,7
Fire 1
Keep 7,8
keeper 3,4
the 1,8

9. Analyzers
“@Andy52 went to school yesterday!”
 StandardAnalyzer
[@Andy52] [went] [school] [yesterday!]
 StopAnalyzer
[Andy] [went] [school] [yesterday]
 SimpleAnalyzer
[andy] [went] [to] [school] [yesterday]
 WhitespaceAnalyzer
[@Andy52] [went] [to] [school] [yesterday]
 KeywordAnalyzer
[@Andy52 went to school yesterday!]

10. What known apps use that?
 Twitter
 Linked In
 My Space

11. That’s all, thanks!