Lucene 4.3 Example

LuceneMain.scala

import scala.Array.canBuildFrom
import org.apache.lucene.analysis.standard.StandardAnalyzer
import org.apache.lucene.document.Document
import org.apache.lucene.document.Field
import org.apache.lucene.document.TextField
import org.apache.lucene.index.DirectoryReader
import org.apache.lucene.index.IndexWriter
import org.apache.lucene.index.IndexWriterConfig
import org.apache.lucene.queryparser.flexible.standard.StandardQueryParser
import org.apache.lucene.search.IndexSearcher
import org.apache.lucene.search.TopScoreDocCollector
import org.apache.lucene.store.RAMDirectory
import org.apache.lucene.util.Version

object LuceneMain {

  def main(args: Array[String]) {

    val luceneIndexDir = new RAMDirectory

    //Indexing content
    val analyzer = new StandardAnalyzer(Version.LUCENE_43)
    val indexWriterConfig = new IndexWriterConfig(Version.LUCENE_43, analyzer)
    val indexWriter = new IndexWriter(luceneIndexDir, indexWriterConfig)

    val document = new Document()
    document.add(new TextField("title", "Lucene Architecture Notes", Field.Store.YES))
    document.add(new TextField("content", "Lucene Searching", Field.Store.YES))
    indexWriter addDocument document
    indexWriter.close

    //Time to search
    val indexReader = DirectoryReader open luceneIndexDir
    println(s"Total number of documents : ${indexReader.numDocs}")

    val searcher = new IndexSearcher(indexReader)
    val qp = new StandardQueryParser()
    val query = qp parse ("lucene", "title")
    val resultsCollector = TopScoreDocCollector create (100, true)
    searcher search (query, resultsCollector)

    val result = resultsCollector.topDocs().scoreDocs
    println(s"Found ${result.length} results")
    for {
      each <- result
      doc = searcher.doc(each.doc)
    } println(s"${doc.get("title")}")
  }
}