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Lucene Indexing

Lucene is rich and powerful text search library written in java. Lucene provides full-text indexing in databases and various other objects. lucene will add content to a full text index, then we can perform queries on this index .

lucene is able to generate fast results because, it will search an index instead of searching a text directly. this is similar to searching a book and getting a page number, using index number at the end of the book unlike searching each page.

In Lucene document is the unit of index. index contains one or more documents. document contains one or more fields. for example set of users can be considered as an index. a single user record will be a document and user name address can be fields.

Indexing

is adding documents to Index via an IndexWriter.

Searching

is retrieving documents from an Index via an IndexSearcher. A searching query will be passed to IndexSearcher. Queries can be performed via Lucene Query Language.

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