public static Options parseArgs(String cmdArgs[]) {
      CommandLineParser parser = new GnuParser();
      CmdLineOptions options = getCmdLineOptions();
      try {
        CommandLine cmd = parser.parse(options, cmdArgs, false);

        if (cmd.hasOption(HELP_OPTION)) {
          printUsage(options);
          System.exit(0);
        }

        String[] args = cmd.getArgs();
        if (args.length >= 4 || args.length < 2) {
          String msg = args.length < 2 ? "Missing arguments" : "Too many arguments";
          errorMsg(msg, options);
          System.exit(1);
        }

        String keyspace = args[0];
        String cf = args[1];
        String snapshot = null;
        if (args.length == 3) snapshot = args[2];

        Options opts = new Options(keyspace, cf, snapshot);

        opts.debug = cmd.hasOption(DEBUG_OPTION);
        opts.keepSource = cmd.hasOption(KEEP_SOURCE);

        return opts;
      } catch (ParseException e) {
        errorMsg(e.getMessage(), options);
        return null;
      }
    }
    public static Options parseArgs(String cmdArgs[]) {
      CommandLineParser parser = new GnuParser();
      CmdLineOptions options = getCmdLineOptions();
      try {
        CommandLine cmd = parser.parse(options, cmdArgs, false);

        if (cmd.hasOption(HELP_OPTION)) {
          printUsage(options);
          System.exit(0);
        }

        String[] args = cmd.getArgs();
        if (args.length == 0) {
          System.err.println("No sstables to split");
          printUsage(options);
          System.exit(1);
        }
        Options opts = new Options(Arrays.asList(args));
        opts.debug = cmd.hasOption(DEBUG_OPTION);
        opts.verbose = cmd.hasOption(VERBOSE_OPTION);
        opts.snapshot = !cmd.hasOption(NO_SNAPSHOT_OPTION);
        opts.sizeInMB = DEFAULT_SSTABLE_SIZE;

        if (cmd.hasOption(SIZE_OPTION))
          opts.sizeInMB = Integer.valueOf(cmd.getOptionValue(SIZE_OPTION));

        return opts;
      } catch (ParseException e) {
        errorMsg(e.getMessage(), options);
        return null;
      }
    }
  public static void main(String args[]) throws IOException {
    Options options = Options.parseArgs(args);
    try {
      // load keyspace descriptions.
      DatabaseDescriptor.loadSchemas();

      String ksName = null;
      String cfName = null;
      Map<Descriptor, Set<Component>> parsedFilenames = new HashMap<Descriptor, Set<Component>>();
      for (String filename : options.filenames) {
        File file = new File(filename);
        if (!file.exists()) {
          System.out.println("Skipping inexisting file " + file);
          continue;
        }

        Pair<Descriptor, Component> pair =
            SSTable.tryComponentFromFilename(file.getParentFile(), file.getName());
        if (pair == null) {
          System.out.println("Skipping non sstable file " + file);
          continue;
        }
        Descriptor desc = pair.left;

        if (ksName == null) ksName = desc.ksname;
        else if (!ksName.equals(desc.ksname))
          throw new IllegalArgumentException("All sstables must be part of the same keyspace");

        if (cfName == null) cfName = desc.cfname;
        else if (!cfName.equals(desc.cfname))
          throw new IllegalArgumentException("All sstables must be part of the same column family");

        Set<Component> components =
            new HashSet<Component>(
                Arrays.asList(
                    new Component[] {
                      Component.DATA,
                      Component.PRIMARY_INDEX,
                      Component.FILTER,
                      Component.COMPRESSION_INFO,
                      Component.STATS
                    }));

        Iterator<Component> iter = components.iterator();
        while (iter.hasNext()) {
          Component component = iter.next();
          if (!(new File(desc.filenameFor(component)).exists())) iter.remove();
        }
        parsedFilenames.put(desc, components);
      }

      if (ksName == null || cfName == null) {
        System.err.println("No valid sstables to split");
        System.exit(1);
      }

      // Do not load sstables since they might be broken
      Table table = Table.openWithoutSSTables(ksName);
      ColumnFamilyStore cfs = table.getColumnFamilyStore(cfName);

      String snapshotName = "pre-split-" + System.currentTimeMillis();

      List<SSTableReader> sstables = new ArrayList<SSTableReader>();
      for (Map.Entry<Descriptor, Set<Component>> fn : parsedFilenames.entrySet()) {
        try {
          SSTableReader sstable =
              SSTableReader.openNoValidation(fn.getKey(), fn.getValue(), cfs.metadata);
          sstables.add(sstable);

          if (options.snapshot) {
            File snapshotDirectory =
                Directories.getSnapshotDirectory(sstable.descriptor, snapshotName);
            sstable.createLinks(snapshotDirectory.getPath());
          }

        } catch (Exception e) {
          System.err.println(String.format("Error Loading %s: %s", fn.getKey(), e.getMessage()));
          if (options.debug) e.printStackTrace(System.err);
        }
      }
      if (options.snapshot)
        System.out.println(
            String.format("Pre-split sstables snapshotted into snapshot %s", snapshotName));

      cfs.getDataTracker().markCompacting(sstables);
      for (SSTableReader sstable : sstables) {
        try {
          new SSTableSplitter(cfs, sstable, options.sizeInMB).split();

          // Remove the sstable
          sstable.markCompacted();
          sstable.releaseReference();
        } catch (Exception e) {
          System.err.println(String.format("Error splitting %s: %s", sstable, e.getMessage()));
          if (options.debug) e.printStackTrace(System.err);
        }
      }
      SSTableDeletingTask.waitForDeletions();
      System.exit(0); // We need that to stop non daemonized threads
    } catch (Exception e) {
      System.err.println(e.getMessage());
      if (options.debug) e.printStackTrace(System.err);
      System.exit(1);
    }
  }
  public static void main(String args[]) throws IOException {
    Options options = Options.parseArgs(args);
    try {
      // load keyspace descriptions.
      DatabaseDescriptor.loadSchemas(false);

      if (Schema.instance.getCFMetaData(options.keyspace, options.cf) == null)
        throw new IllegalArgumentException(
            String.format("Unknown keyspace/columnFamily %s.%s", options.keyspace, options.cf));

      Keyspace keyspace = Keyspace.openWithoutSSTables(options.keyspace);
      ColumnFamilyStore cfs = keyspace.getColumnFamilyStore(options.cf);

      OutputHandler handler = new OutputHandler.SystemOutput(false, options.debug);
      Directories.SSTableLister lister = cfs.directories.sstableLister();
      if (options.snapshot != null) lister.onlyBackups(true).snapshots(options.snapshot);
      else lister.includeBackups(false);

      Collection<SSTableReader> readers = new ArrayList<SSTableReader>();

      // Upgrade sstables
      for (Map.Entry<Descriptor, Set<Component>> entry : lister.list().entrySet()) {
        Set<Component> components = entry.getValue();
        if (!components.contains(Component.DATA) || !components.contains(Component.PRIMARY_INDEX))
          continue;

        try {
          SSTableReader sstable =
              SSTableReader.openNoValidation(entry.getKey(), components, cfs.metadata);
          if (sstable.descriptor.version.equals(Descriptor.Version.CURRENT)) continue;
          readers.add(sstable);
        } catch (Exception e) {
          JVMStabilityInspector.inspectThrowable(e);
          System.err.println(String.format("Error Loading %s: %s", entry.getKey(), e.getMessage()));
          if (options.debug) e.printStackTrace(System.err);

          continue;
        }
      }

      int numSSTables = readers.size();
      handler.output("Found " + numSSTables + " sstables that need upgrading.");

      for (SSTableReader sstable : readers) {
        try {
          Upgrader upgrader = new Upgrader(cfs, sstable, handler);
          upgrader.upgrade();

          if (!options.keepSource) {
            // Remove the sstable (it's been copied by upgrade)
            System.out.format("Deleting table %s.%n", sstable.descriptor.baseFilename());
            sstable.markObsolete();
            sstable.selfRef().release();
          }
        } catch (Exception e) {
          System.err.println(String.format("Error upgrading %s: %s", sstable, e.getMessage()));
          if (options.debug) e.printStackTrace(System.err);
        }
      }
      CompactionManager.instance.finishCompactionsAndShutdown(5, TimeUnit.MINUTES);
      SSTableDeletingTask.waitForDeletions();
      System.exit(0);
    } catch (Exception e) {
      System.err.println(e.getMessage());
      if (options.debug) e.printStackTrace(System.err);
      System.exit(1);
    }
  }