序列化笔记

「爱情、让人受尽委屈。」 2024-03-26 17:39 26阅读 0赞

1.序列化对应的网络结构模型为应用层

2.并不推荐使用java自带的序列化工具包，因为安全性较差，用户可以随意的修改序列化后的数据

且不支持跨语言调用，同时性能较其他框架实现的要差。

实现自带的序列化只需要实现serializable接口

@AllArgsConstructor
    @NoArgsConstructor
    @Getter
    @Builder
    @ToString
    public class RpcRequest implements Serializable {
        private static final long serialVersionUID = 1905122041950251207L;
        private String requestId;
        private String interfaceName;
        private String methodName;
        private Object[] parameters;
        private Class<?>[] paramTypes;
        private RpcMessageTypeEnum rpcMessageTypeEnum;
    }

注意：

static修饰的变量属于类，是在方法区的，本身是不会被序列化的

如果不想被序列化的变量可以采用transient

经历过transien修饰的序列化后的变量默认都会反序列化为对应变量的初始值，int->0

3.推荐使用Kryo

@Slf4j
    public class KryoSerializer implements Serializer {
    
        /**
         * Because Kryo is not thread safe. So, use ThreadLocal to store Kryo objects
         */
        private final ThreadLocal<Kryo> kryoThreadLocal = ThreadLocal.withInitial(() -> {
            Kryo kryo = new Kryo();
            kryo.register(RpcResponse.class);
            kryo.register(RpcRequest.class);
            return kryo;
        });
    
        @Override
        public byte[] serialize(Object obj) {
            try (ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
                 Output output = new Output(byteArrayOutputStream)) {
                Kryo kryo = kryoThreadLocal.get();
                // Object->byte:将对象序列化为byte数组
                kryo.writeObject(output, obj);
                kryoThreadLocal.remove();
                return output.toBytes();
            } catch (Exception e) {
                throw new SerializeException("Serialization failed");
            }
        }
    
        @Override
        public <T> T deserialize(byte[] bytes, Class<T> clazz) {
            try (ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(bytes);
                 Input input = new Input(byteArrayInputStream)) {
                Kryo kryo = kryoThreadLocal.get();
                // byte->Object:从byte数组中反序列化出对象
                Object o = kryo.readObject(input, clazz);
                kryoThreadLocal.remove();
                return clazz.cast(o);
            } catch (Exception e) {
                throw new SerializeException("Deserialization failed");
            }
        }
    
    }