需求描述：为某个文件夹A下的所有后缀名为.txt的文件创建索引，索引文件存放于文件夹B下

开发环境：Lucene 3.4.0 + eclipse indigo + jdk1.7.0，配置如下

为文件创建索引的是mytest包下的indexer类，具体代码如下：

 

package mytest; import org.apache.lucene.index.IndexWriter; import org.apache.lucene.analysis.standard.StandardAnalyzer; import org.apache.lucene.document.Document; import org.apache.lucene.document.Field; import org.apache.lucene.store.FSDirectory; import org.apache.lucene.store.Directory; import org.apache.lucene.util.Version; import java.io.File; import java.io.FileFilter; import java.io.IOException; import java.io.FileReader; // From chapter 1 public class Indexer {
    public static void main(String[] args) throws Exception {
        String indexDir = "E://eclipse//javaProject//lucene-3.4.0//indexDir";         //1     String dataDir = "E://eclipse//javaProject//lucene-3.4.0//dataDir";          //2 long start = System.currentTimeMillis();     Indexer indexer = new Indexer(indexDir); int numIndexed; try {
          numIndexed = indexer.index(dataDir, new TextFilesFilter());     } finally {
          indexer.close();     } long end = System.currentTimeMillis();     System.out.println("Indexing " + numIndexed + " files took "       + (end - start) + " milliseconds");   } private IndexWriter writer; public Indexer(String indexDir) throws IOException {
        Directory dir = FSDirectory.open(new File(indexDir));     writer = new IndexWriter(dir,            //3                  new StandardAnalyzer(       //3                      Version.LUCENE_34),//3                  true,                       //3                              IndexWriter.MaxFieldLength.UNLIMITED); //3   } public void close() throws IOException {
        writer.close();                             //4   } public int index(String dataDir, FileFilter filter) throws Exception {
        File[] files = new File(dataDir).listFiles(); for (File f: files) {
    if (!f.isDirectory() &&           !f.isHidden() &&           f.exists() &&           f.canRead() &&           (filter == null || filter.accept(f))) {
            indexFile(f);       }     } return writer.numDocs();                     //5   } private static class TextFilesFilter implements FileFilter {
    public boolean accept(File path) {
    return path.getName().toLowerCase()        //6              .endsWith(".txt");                  //6     }   } protected Document getDocument(File f) throws Exception {
        Document doc = new Document();     doc.add(new Field("contents", new FileReader(f)));      //7     doc.add(new Field("filename", f.getName(),              //8                 Field.Store.YES, Field.Index.NOT_ANALYZED));//8     doc.add(new Field("fullpath", f.getCanonicalPath(),     //9                 Field.Store.YES, Field.Index.NOT_ANALYZED));//9     return doc;   } private void indexFile(File f) throws Exception {
        System.out.println("Indexing " + f.getCanonicalPath());     Document doc = getDocument(f);     writer.addDocument(doc);                              //10   } } /* #1 Create index in this directory #2 Index *.txt files from this directory #3 Create Lucene IndexWriter #4 Close IndexWriter #5 Return number of documents indexed #6 Index .txt files only, using FileFilter #7 Index file content #8 Index file name #9 Index file full path #10 Add document to Lucene index */

 

程序运行结果如下：

程序运行结束后，在指定目录下生成索引文件：

 

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