@Override public void run() { try { DirectoryReader open = null; for (int i = 0; i < num; i++) { Document doc = new Document(); // docs.nextDoc(); BytesRef br = new BytesRef("test"); doc.add(newStringField("id", br, Field.Store.NO)); writer.updateDocument(new Term("id", br), doc); if (random().nextInt(3) == 0) { if (open == null) { open = DirectoryReader.open(writer, true); } DirectoryReader reader = DirectoryReader.openIfChanged(open); if (reader != null) { open.close(); open = reader; } assertEquals( "iter: " + i + " numDocs: " + open.numDocs() + " del: " + open.numDeletedDocs() + " max: " + open.maxDoc(), 1, open.numDocs()); } } if (open != null) { open.close(); } } catch (Exception e) { throw new RuntimeException(e); } }