code: public Map<String, String> decode(byte[] bytes) throws DeserializationException {
          Map<String, String> map = new HashMap<String, String>();
          if (bytes == null || bytes.length == 0) {
              return map;
          }
  
          UnsafeByteArrayInputStream in = new UnsafeByteArrayInputStream(bytes);
          try {
              while (in.available() > 0) {
                  String key = readString(in);
                  String value = readString(in);
                  map.put(key, value);
              }
              return map;
          } catch (IOException ex) {
              throw new DeserializationException(ex.getMessage(), ex);
          }
      }
docs: 简单 map 的反序列化过程, 用来反序列化 bolt 的 header
  <p>
  {@link SofaRpcSerialization#deserializeHeader(com.alipay.remoting.rpc.RequestCommand)}
  
  @param bytes bolt header
  @return 反序列化后的 Map 对象
  @throws DeserializationException DeserializationException