public static void addField(String dir, String fieldName, FlamdexReader r, final long[] cache) throws IOException { final File tempFile = new File(dir, "temp-" + fieldName + "-" + UUID.randomUUID() + ".intarray.bin"); try { final MMapBuffer buffer = new MMapBuffer( tempFile, 0, 4 * cache.length, FileChannel.MapMode.READ_WRITE, ByteOrder.nativeOrder()); try { final IntArray indices = buffer.memory().intArray(0, cache.length); for (int i = 0; i < cache.length; ++i) { indices.set(i, i); } log.debug("sorting"); Quicksortables.sort( new Quicksortable() { @Override public void swap(int i, int j) { final int t = indices.get(i); indices.set(i, indices.get(j)); indices.set(j, t); } @Override public int compare(int i, int j) { final long ii = cache[indices.get(i)]; final long ij = cache[indices.get(j)]; return ii < ij ? -1 : ii > ij ? 1 : indices.get(i) < indices.get(j) ? -1 : indices.get(i) > indices.get(j) ? 1 : 0; } }, cache.length); log.debug("writing field " + fieldName); final SimpleFlamdexWriter w = new SimpleFlamdexWriter(dir, r.getNumDocs(), false); final IntFieldWriter ifw = w.getIntFieldWriter(fieldName, true); long prev = 0; boolean prevInitialized = false; for (int i = 0; i < cache.length; ++i) { final long cur = cache[indices.get(i)]; if (!prevInitialized || cur != prev) { ifw.nextTerm(cur); prev = cur; prevInitialized = true; } ifw.nextDoc(indices.get(i)); } ifw.close(); w.close(); } finally { try { buffer.close(); } catch (IOException e) { log.error("error closing MMapBuffer", e); } } } finally { if (!tempFile.delete()) { log.warn("unable to delete temp file " + tempFile); } } }