Lucene, sample JAVA code to Index a file folder

Please find below the Lucene sample code to index the files inside a folder. This code will index ( or create fields for ) the file path, file title, modified date and contents of the file.

This java code is expecting the index path ( where the index files will be created ) and file folder path as program arguments like  "java IndexFiles  [-index INDEX_PATH] [-docs DOCS_PATH]" .

The logic of the code is to iterate through each file in the folder and call the method indexDoc(), where the above said fields are created and added to a Document object. This means that for each file there will be a document object and these document objects will be added to IndexWriter.

Please find below the screen shot of the indexd file folder :

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Date;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.NumericField;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;

public class IndexFiles {
 public static void main(String[] args) {
  String usage = "java IndexFiles  [-index INDEX_PATH] [-docs DOCS_PATH] \n\n"
   + "This indexes the documents in DOCS_PATH, creating a Lucene index in"
   + "INDEX_PATH that can be searched with SearchFiles";
  String indexPath = "index";
  String docsPath = null;
  for (int i = 0; i < args.length; i++) {
   if ("-index".equals(args[i])) {
    indexPath = args[i + 1];
    i++;
   } else if ("-docs".equals(args[i])) {
    docsPath = args[i + 1];
    i++;
   }
  }
  if (docsPath == null) {
   System.err.println("Usage: " + usage);
   System.exit(1);
  }
  final File docDir = new File(docsPath);
  if (!docDir.exists() || !docDir.canRead()) {
   System.out.println("Document directory "
   + docDir.getAbsolutePath()
   + "does not exist or is not readable, please check the path");
   System.exit(1);
  }
  Date start = new Date();
  try {
   System.out.println("Indexing to directory '" + indexPath + "'...");
   Directory dir = FSDirectory.open(new File(indexPath));

   Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_31);
   IndexWriterConfig iwc = new IndexWriterConfig(Version.LUCENE_31,analyzer);
   iwc.setOpenMode(OpenMode.CREATE);
   IndexWriter writer = new IndexWriter(dir, iwc);
   findFilesAndIndex(writer, docDir);

   writer.close();
   Date end = new Date();
   System.out.println(end.getTime() - start.getTime()+ " total milliseconds");
  } catch (IOException e) {
   System.out.println(" caught a " + e.getClass()+ "\n with message: " + e.getMessage());
  }
 }

 static void findFilesAndIndex(IndexWriter writer, File file) throws IOException {
  FileInputStream fis = null;
  try{
  if (file.canRead()) {
   if (file.isDirectory()) {
   String[] files = file.list();
   if (files != null) {
    for (int i = 0; i < files.length; i++) {
    findFilesAndIndex(writer, new File(file, files[i]));
    }
   }
   } else {
    fis = new FileInputStream(file);
    indexDoc(writer, file,fis);
   }
  }
  }catch (IOException e) {
   System.out.println(" caught a " + e.getClass()+ "\n with message: " + e.getMessage());
  }finally {
   if(fis != null){
    fis.close();
   }
  }
 }

 static void indexDoc(IndexWriter writer, File file,FileInputStream fis) throws IOException {
  Document doc = new Document();
  Field pathField = new Field("path", file.getPath(),Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS);
  pathField.setOmitTermFreqAndPositions(true);
  doc.add(pathField);

  Field titleField = new Field("title", file.getName(),Field.Store.YES, Field.Index.NOT_ANALYZED_NO_NORMS);
  pathField.setOmitTermFreqAndPositions(true);
  doc.add(titleField);

  NumericField modifiedField = new NumericField("modified");
  modifiedField.setLongValue(file.lastModified());
  doc.add(modifiedField);

  doc.add(new Field("contents", new BufferedReader(new InputStreamReader(fis, "UTF-8"))));

  System.out.println("adding " + file);
  writer.addDocument(doc);
 }
}