import com.google.protos.ipc.invalidation.Client.PersistentStateBlob; //导入依赖的package包/类
/**
 * Deserializes a Ticl state blob. Returns either the parsed state or {@code null}
 * if it could not be parsed.
 */
public static PersistentTiclState deserializeState(Logger logger, byte[] stateBlobBytes,
    DigestFunction digestFn) {
  PersistentStateBlob stateBlob;
  try {
    // Try parsing the envelope protocol buffer.
    stateBlob = PersistentStateBlob.parseFrom(stateBlobBytes);
  } catch (InvalidProtocolBufferException exception) {
    logger.severe("Failed deserializing Ticl state: %s", exception.getMessage());
    return null;
  }

  // Check the mac in the envelope against the recomputed mac from the state.
  PersistentTiclState ticlState = stateBlob.getTiclState();
  ByteString mac = generateMac(ticlState, digestFn);
  if (!TypedUtil.<ByteString>equals(mac, stateBlob.getAuthenticationCode())) {
    logger.warning("Ticl state failed MAC check: computed %s vs %s", mac,
        stateBlob.getAuthenticationCode());
    return null;
  }
  return ticlState;
}
 

import com.google.protos.ipc.invalidation.Client.PersistentStateBlob; //导入依赖的package包/类
public static PersistentStateBlob newPersistentStateBlob(PersistentTiclState state,
    ByteString mac) {
  return PersistentStateBlob.newBuilder()
      .setTiclState(state)
      .setAuthenticationCode(mac)
      .build();
}