// LUCENE-1274: test writer.prepareCommit()
  public void testPrepareCommitRollback() throws IOException {
    MockDirectoryWrapper dir = newDirectory();
    dir.setPreventDoubleWrite(false);

    IndexWriter writer =
        new IndexWriter(
            dir,
            newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random()))
                .setMaxBufferedDocs(2)
                .setMergePolicy(newLogMergePolicy(5)));
    writer.commit();

    for (int i = 0; i < 23; i++) TestIndexWriter.addDoc(writer);

    DirectoryReader reader = DirectoryReader.open(dir);
    assertEquals(0, reader.numDocs());

    writer.prepareCommit();

    IndexReader reader2 = DirectoryReader.open(dir);
    assertEquals(0, reader2.numDocs());

    writer.rollback();

    IndexReader reader3 = DirectoryReader.openIfChanged(reader);
    assertNull(reader3);
    assertEquals(0, reader.numDocs());
    assertEquals(0, reader2.numDocs());
    reader.close();
    reader2.close();

    writer =
        new IndexWriter(
            dir, newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random())));
    for (int i = 0; i < 17; i++) TestIndexWriter.addDoc(writer);

    reader = DirectoryReader.open(dir);
    assertEquals(0, reader.numDocs());
    reader.close();

    writer.prepareCommit();

    reader = DirectoryReader.open(dir);
    assertEquals(0, reader.numDocs());
    reader.close();

    writer.commit();
    reader = DirectoryReader.open(dir);
    assertEquals(17, reader.numDocs());
    reader.close();
    writer.close();
    dir.close();
  }
  public void testTransactions() throws Throwable {
    // we cant use non-ramdir on windows, because this test needs to double-write.
    MockDirectoryWrapper dir1 = new MockDirectoryWrapper(random(), new RAMDirectory());
    MockDirectoryWrapper dir2 = new MockDirectoryWrapper(random(), new RAMDirectory());
    dir1.setPreventDoubleWrite(false);
    dir2.setPreventDoubleWrite(false);
    dir1.failOn(new RandomFailure());
    dir2.failOn(new RandomFailure());
    dir1.setFailOnOpenInput(false);
    dir2.setFailOnOpenInput(false);

    // We throw exceptions in deleteFile, which creates
    // leftover files:
    dir1.setAssertNoUnrefencedFilesOnClose(false);
    dir2.setAssertNoUnrefencedFilesOnClose(false);

    initIndex(dir1);
    initIndex(dir2);

    TimedThread[] threads = new TimedThread[3];
    int numThread = 0;

    IndexerThread indexerThread = new IndexerThread(this, dir1, dir2, threads);
    threads[numThread++] = indexerThread;
    indexerThread.start();

    SearcherThread searcherThread1 = new SearcherThread(this, dir1, dir2, threads);
    threads[numThread++] = searcherThread1;
    searcherThread1.start();

    SearcherThread searcherThread2 = new SearcherThread(this, dir1, dir2, threads);
    threads[numThread++] = searcherThread2;
    searcherThread2.start();

    for (int i = 0; i < numThread; i++) threads[i].join();

    for (int i = 0; i < numThread; i++) assertTrue(!threads[i].failed);
    dir1.close();
    dir2.close();
  }
  public void testWriterAfterCrash() throws IOException {
    // This test relies on being able to open a reader before any commit
    // happened, so we must create an initial commit just to allow that, but
    // before any documents were added.
    IndexWriter writer = initIndex(random, true);
    MockDirectoryWrapper dir = (MockDirectoryWrapper) writer.getDirectory();
    dir.setPreventDoubleWrite(false);
    crash(writer);
    writer = initIndex(random, dir, false);
    writer.close();

    IndexReader reader = IndexReader.open(dir, false);
    assertTrue(reader.numDocs() < 314);
    reader.close();
    dir.close();
  }
  @Slow
  public void testNoWaitClose() throws Throwable {
    Directory directory = newDirectory();

    if (directory instanceof MockDirectoryWrapper) {
      ((MockDirectoryWrapper) directory).setPreventDoubleWrite(false);
    }

    final Document doc = new Document();
    FieldType customType = new FieldType(TextField.TYPE_NOT_STORED);
    customType.setTokenized(false);

    Field idField = newField("id", "", customType);
    doc.add(idField);

    for (int pass = 0; pass < 2; pass++) {
      if (VERBOSE) {
        System.out.println("TEST: pass="******"TEST: iter=" + iter);
        }
        for (int j = 0; j < 199; j++) {
          idField.setStringValue(Integer.toString(iter * 201 + j));
          writer.addDocument(doc);
        }

        int delID = iter * 199;
        for (int j = 0; j < 20; j++) {
          writer.deleteDocuments(new Term("id", Integer.toString(delID)));
          delID += 5;
        }

        writer.commit();

        // Force a bunch of merge threads to kick off so we
        // stress out aborting them on close:
        ((LogMergePolicy) writer.getConfig().getMergePolicy()).setMergeFactor(2);

        final IndexWriter finalWriter = writer;
        final AtomicReference<Throwable> failure = new AtomicReference<>();
        Thread t1 =
            new Thread() {
              @Override
              public void run() {
                boolean done = false;
                while (!done) {
                  for (int i = 0; i < 100; i++) {
                    try {
                      finalWriter.addDocument(doc);
                    } catch (AlreadyClosedException e) {
                      done = true;
                      break;
                    } catch (NullPointerException e) {
                      done = true;
                      break;
                    } catch (Throwable e) {
                      e.printStackTrace(System.out);
                      failure.set(e);
                      done = true;
                      break;
                    }
                  }
                  Thread.yield();
                }
              }
            };

        t1.start();

        writer.close();
        t1.join();

        if (failure.get() != null) {
          throw failure.get();
        }

        // Make sure reader can read
        IndexReader reader = DirectoryReader.open(directory);
        reader.close();

        // Reopen
        writer =
            new IndexWriter(
                directory,
                newIndexWriterConfig(new MockAnalyzer(random()))
                    .setOpenMode(OpenMode.APPEND)
                    .setMergePolicy(newLogMergePolicy())
                    .setCommitOnClose(false));
      }
      writer.close();
    }

    directory.close();
  }
  /*
   * Simple test for "commit on close": open writer, then
   * add a bunch of docs, making sure reader does not see
   * them until writer has closed.  Then instead of
   * closing the writer, call abort and verify reader sees
   * nothing was added.  Then verify we can open the index
   * and add docs to it.
   */
  public void testCommitOnCloseAbort() throws IOException {
    MockDirectoryWrapper dir = newDirectory();
    IndexWriter writer =
        new IndexWriter(
            dir,
            newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random()))
                .setMaxBufferedDocs(10));
    for (int i = 0; i < 14; i++) {
      TestIndexWriter.addDoc(writer);
    }
    writer.close();

    Term searchTerm = new Term("content", "aaa");
    IndexReader reader = DirectoryReader.open(dir);
    IndexSearcher searcher = new IndexSearcher(reader);
    ScoreDoc[] hits = searcher.search(new TermQuery(searchTerm), null, 1000).scoreDocs;
    assertEquals("first number of hits", 14, hits.length);
    reader.close();

    writer =
        new IndexWriter(
            dir,
            newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random()))
                .setOpenMode(OpenMode.APPEND)
                .setMaxBufferedDocs(10));
    for (int j = 0; j < 17; j++) {
      TestIndexWriter.addDoc(writer);
    }
    // Delete all docs:
    writer.deleteDocuments(searchTerm);

    reader = DirectoryReader.open(dir);
    searcher = new IndexSearcher(reader);
    hits = searcher.search(new TermQuery(searchTerm), null, 1000).scoreDocs;
    assertEquals("reader incorrectly sees changes from writer", 14, hits.length);
    reader.close();

    // Now, close the writer:
    writer.rollback();

    TestIndexWriter.assertNoUnreferencedFiles(dir, "unreferenced files remain after rollback()");

    reader = DirectoryReader.open(dir);
    searcher = new IndexSearcher(reader);
    hits = searcher.search(new TermQuery(searchTerm), null, 1000).scoreDocs;
    assertEquals("saw changes after writer.abort", 14, hits.length);
    reader.close();

    // Now make sure we can re-open the index, add docs,
    // and all is good:
    writer =
        new IndexWriter(
            dir,
            newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random()))
                .setOpenMode(OpenMode.APPEND)
                .setMaxBufferedDocs(10));

    // On abort, writer in fact may write to the same
    // segments_N file:
    dir.setPreventDoubleWrite(false);

    for (int i = 0; i < 12; i++) {
      for (int j = 0; j < 17; j++) {
        TestIndexWriter.addDoc(writer);
      }
      IndexReader r = DirectoryReader.open(dir);
      searcher = new IndexSearcher(r);
      hits = searcher.search(new TermQuery(searchTerm), null, 1000).scoreDocs;
      assertEquals("reader incorrectly sees changes from writer", 14, hits.length);
      r.close();
    }

    writer.close();
    IndexReader r = DirectoryReader.open(dir);
    searcher = new IndexSearcher(r);
    hits = searcher.search(new TermQuery(searchTerm), null, 1000).scoreDocs;
    assertEquals("didn't see changes after close", 218, hits.length);
    r.close();

    dir.close();
  }
  /*
   * Verify that calling forceMerge when writer is open for
   * "commit on close" works correctly both for rollback()
   * and close().
   */
  public void testCommitOnCloseForceMerge() throws IOException {
    MockDirectoryWrapper dir = newDirectory();
    // Must disable throwing exc on double-write: this
    // test uses IW.rollback which easily results in
    // writing to same file more than once
    dir.setPreventDoubleWrite(false);
    IndexWriter writer =
        new IndexWriter(
            dir,
            newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random()))
                .setMaxBufferedDocs(10)
                .setMergePolicy(newLogMergePolicy(10)));
    for (int j = 0; j < 17; j++) {
      TestIndexWriter.addDocWithIndex(writer, j);
    }
    writer.close();

    writer =
        new IndexWriter(
            dir,
            newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random()))
                .setOpenMode(OpenMode.APPEND));
    writer.forceMerge(1);

    // Open a reader before closing (commiting) the writer:
    DirectoryReader reader = DirectoryReader.open(dir);

    // Reader should see index as multi-seg at this
    // point:
    assertTrue("Reader incorrectly sees one segment", reader.getSequentialSubReaders().size() > 1);
    reader.close();

    // Abort the writer:
    writer.rollback();
    TestIndexWriter.assertNoUnreferencedFiles(dir, "aborted writer after forceMerge");

    // Open a reader after aborting writer:
    reader = DirectoryReader.open(dir);

    // Reader should still see index as multi-segment
    assertTrue("Reader incorrectly sees one segment", reader.getSequentialSubReaders().size() > 1);
    reader.close();

    if (VERBOSE) {
      System.out.println("TEST: do real full merge");
    }
    writer =
        new IndexWriter(
            dir,
            newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random()))
                .setOpenMode(OpenMode.APPEND));
    writer.forceMerge(1);
    writer.close();

    if (VERBOSE) {
      System.out.println("TEST: writer closed");
    }
    TestIndexWriter.assertNoUnreferencedFiles(dir, "aborted writer after forceMerge");

    // Open a reader after aborting writer:
    reader = DirectoryReader.open(dir);

    // Reader should see index as one segment
    assertEquals(
        "Reader incorrectly sees more than one segment",
        1,
        reader.getSequentialSubReaders().size());
    reader.close();
    dir.close();
  }