jediscluster的maxAttempts的理解

1.我们知道进行redis配置的时候可以配置maxAttempts参数，那么这个参数的含义是什么呢？

} catch (JedisNoReachableClusterNodeException jnrcne) {
  throw jnrcne;
} catch (JedisConnectionException jce) {
  // release current connection before recursion
  releaseConnection(connection);
  connection = null;

  if (attempts <= 1) {
    //We need this because if node is not reachable anymore - we need to finally initiate slots
    //renewing, or we can stuck with cluster state without one node in opposite case.
    //But now if maxAttempts = [1 or 2] we will do it too often.
    //TODO make tracking of successful/unsuccessful operations for node - do renewing only
    //if there were no successful responses from this node last few seconds
    this.connectionHandler.renewSlotCache();
  }

  return runWithRetries(slot, attempts - 1, tryRandomNode, redirect);
}`
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最核心的代码是catch(JedisConnectionException) 异常的时候回进行重试指定的次数。
2.问题来了，什么情况下会抛出JedisConnectionException呢？连接超时或者读取超时会导致这个异常吗？是仅仅连接超时才会重试，还是连接超时或者读取超时都会重试？

  private static void sendCommand(final RedisOutputStream os, final byte[] command,
      final byte[]... args) {
    try {
      os.write(ASTERISK_BYTE);
      os.writeIntCrLf(args.length + 1);
      os.write(DOLLAR_BYTE);
      os.writeIntCrLf(command.length);
      os.write(command);
      os.writeCrLf();

      for (final byte[] arg : args) {
        os.write(DOLLAR_BYTE);
        os.writeIntCrLf(arg.length);
        os.write(arg);
        os.writeCrLf();
      }
    } catch (IOException e) {
      throw new JedisConnectionException(e);
    }
  }
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可以看到向redis发送命令的代码，只要是IOException的时候redis都会转成JedisConnectionException向上抛出，所以可以知道，不管是连接超时ConnectionException还是读取超时SocketTimeOutException，都会进行重试，而重试的次数就是MaxAttempts参数指定的