private static void deleteCache() throws Exception {
CachingAvatarZooKeeperClient zk = ((DistributedAvatarFileSystem) cluster
.getFileSystem()).failoverHandler.zk;
GetStat stat = zk.new GetStat(cluster.getFileSystem().getUri());
stat.getDataFile(zk.getCacheDir()).delete();
stat.getLockFile(zk.getCacheDir()).delete();
GetAddr addr = zk.new GetAddr(cluster.getFileSystem().getUri(), null, false);
addr.getDataFile(zk.getCacheDir()).delete();
addr.getLockFile(zk.getCacheDir()).delete();
}