public ArtifactData getCandidate(String key) throws Exception {
   ArtifactData data = getCandidateAsync(key);
   if (data != null) {
     data.sync();
   }
   return data;
 }
  public void update(UpdateMemo memo) throws Exception {

    ArtifactData target = put(memo.best.urls.iterator().next());

    memo.current.version = new Version(memo.best.version);
    target.sync();
    memo.current.sha = target.sha;
    // memo.current.dependencies = target.dependencies;
    // memo.current.dependencies.add((new File(repoDir,
    // Hex.toHexString(target.sha))).getCanonicalPath());
    // memo.current.runbundles = target.runbundles;
    // memo.current.description = target.description;
    memo.current.time = target.time;

    if (memo.current instanceof ServiceData) {
      Service service = getService((ServiceData) memo.current);
      service.remove();
      createService((ServiceData) memo.current);
      IO.delete(new File(IO.getFile(serviceDir, memo.current.name), "data"));
      storeData(new File(IO.getFile(serviceDir, memo.current.name), "data"), memo.current);
    } else {
      platform.deleteCommand(memo.current);
      createCommand(memo.current, false);
      IO.delete(IO.getFile(commandDir, memo.current.name));
      storeData(IO.getFile(commandDir, memo.current.name), memo.current);
    }
  }