}
_usingLocalTmpindex = true;
if (_localTmpWriter == null) {
String localDirPath = System.getProperty(JAVA_IO_TMPDIR);
_localTmpPath = new File(localDirPath, UUID.randomUUID().toString() + ".tmp");
SimpleFSDirectory directory = new SimpleFSDirectory(_localTmpPath);
_localTmpDir = new ProgressableDirectory(directory, getProgressable());
_localTmpWriter = new IndexWriter(_localTmpDir, _overFlowConf.clone());
// The local tmp writer has merging disabled so the first document in is
// going to be doc 0.
// Therefore the first document added is the prime doc