Lucene 和solr的區別
solr和lucene的區別：
A simple way to conceptualize the relationship between Solr and Lucene is that of a car and its engine. You can't drive an engine, but you can drive a car. Similarly, Lucene is a programmatic library which you can't use as-is, whereas Solr is a complete application which you can use out-of-box.
Lucene是一個開放原始碼的全文檢索引擎工具包，即它不是一個完整的全文檢索引擎，而是一個全文檢索引擎的架構，提供了完整的查詢引擎和索引引擎，部分文字分析引擎（英文與德文兩種西方語言）。Lucene的目的是為軟體開發人員提供一個簡單易用的工具包，以方便的在目標系統中實現全文檢索的功能，或者是以此為基礎建立起完整的全文檢索引擎.
Solr是一個高效能，採用Java5開發，基於Lucene的全文搜尋伺服器。同時對其進行了擴充套件，提供了比Lucene更為豐富的查詢語言，同時實現了可配置、可擴充套件並對查詢效能進行了優化，並且提供了一個完善的功能管理介面，是一款非常優秀的全文搜尋引擎。它對外提供類似於Web-service的API介面。使用者可以通過http請求，向搜尋引擎伺服器提交一定格式的XML檔案，生成索引；也可以通過Http Solr Get操作提出查詢請求，並得到XML格式的返回結果；
Solr和Lucene的本質區別有以下三點：搜尋伺服器，企業級和管理。Lucene本質上是搜尋庫，不是獨立的應用程式，而Solr是。Lucene專注於搜尋底層的建設，而Solr專注於企業應用。Lucene不負責支撐搜尋服務所必須的管理，而Solr負責。所以說，一句話概括Solr: Solr是Lucene面向企業搜尋應用的擴充套件。
What is Solr?
Apache Solr is a web application built around Lucene with all kinds of goodies.
It adds functionality like
- XML/HTTP and JSON APIs
- Hit highlighting
- Faceted Search and Filtering
- Geospatial Search
- Fast Incremental Updates and Index Replication
- Caching
- Replication
- Web administration interface etc
Unlike Lucene, Solr is a web application (WAR) which can be deployed in any servlet container, e.g. Jetty, Tomcat, Resin, etc.
Solr can be installed and used by non-programmers. Lucene cannot.
Is it well supported?
Yes! The Solr community is very vibrant and helpful.
Can Solr indexes be read by Lucene and vice-versa?
Since Solr uses Lucene under the hood, Solr indexes and Lucene indexes are one and the same thing.
There is technically no such thing as a Solr index, only a Lucene index created by a Solr instance.
When should I use Lucene then?
If you need to embed search functionality into a desktop application for example, Lucene is the more appropriate choice.
For situations where you have very customized requirements requiring low-level access to the Lucene API classes, Solr may be more a hindrance than a help, since it is an extra layer of indirection.