diff --git a/src/protocol/HttpMessage.cc b/src/protocol/HttpMessage.cc
index 11c2c646..e142c00b 100644
--- a/src/protocol/HttpMessage.cc
+++ b/src/protocol/HttpMessage.cc
@@ -19,6 +19,7 @@
 #include <errno.h>
 #include <stdlib.h>
 #include <string.h>
+#include <utility>
 #include "HttpMessage.h"
 
 namespace protocol
@@ -222,11 +223,9 @@ inline int HttpMessage::append(const void *buf, size_t *size)
 	return ret;
 }
 
-HttpMessage::HttpMessage(HttpMessage&& msg)
+HttpMessage::HttpMessage(HttpMessage&& msg) :
+	ProtocolMessage(std::move(msg))
 {
-	this->size_limit = msg.size_limit;
-	msg.size_limit = (size_t)-1;
-
 	this->parser = msg.parser;
 	msg.parser = NULL;
 
@@ -243,8 +242,7 @@ HttpMessage& HttpMessage::operator = (HttpMessage&& msg)
 {
 	if (&msg != this)
 	{
-		this->size_limit = msg.size_limit;
-		msg.size_limit = (size_t)-1;
+		*(ProtocolMessage *)this = std::move(msg);
 
 		http_parser_deinit(this->parser);
 		delete this->parser;
diff --git a/src/protocol/HttpMessage.h b/src/protocol/HttpMessage.h
index 8cd372ba..bb2b7e82 100644
--- a/src/protocol/HttpMessage.h
+++ b/src/protocol/HttpMessage.h
@@ -278,12 +278,8 @@ public:
 
 	/* for std::move() */
 public:
-	HttpRequest(HttpRequest&& req) : HttpMessage(std::move(req)) { }
-	HttpRequest& operator = (HttpRequest&& req)
-	{
-		*(HttpMessage *)this = std::move(req);
-		return *this;
-	}
+	HttpRequest(HttpRequest&& req) = default;
+	HttpRequest& operator = (HttpRequest&& req) = default;
 };
 
 class HttpResponse : public HttpMessage
@@ -361,12 +357,8 @@ public:
 
 	/* for std::move() */
 public:
-	HttpResponse(HttpResponse&& resp) : HttpMessage(std::move(resp)) { }
-	HttpResponse& operator = (HttpResponse&& resp)
-	{
-		*(HttpMessage *)this = std::move(resp);
-		return *this;
-	}
+	HttpResponse(HttpResponse&& resp) = default;
+	HttpResponse& operator = (HttpResponse&& resp) = default;
 };
 
 }
diff --git a/src/protocol/KafkaMessage.cc b/src/protocol/KafkaMessage.cc
index 3beb1ad5..5f121d02 100644
--- a/src/protocol/KafkaMessage.cc
+++ b/src/protocol/KafkaMessage.cc
@@ -1620,11 +1620,9 @@ KafkaMessage::~KafkaMessage()
 	}
 }
 
-KafkaMessage::KafkaMessage(KafkaMessage&& msg)
+KafkaMessage::KafkaMessage(KafkaMessage&& msg) :
+	ProtocolMessage(std::move(msg))
 {
-	this->size_limit = msg.size_limit;
-	msg.size_limit = (size_t)-1;
-
 	this->parser = msg.parser;
 	this->stream = msg.stream;
 	msg.parser = NULL;
@@ -1651,8 +1649,7 @@ KafkaMessage& KafkaMessage::operator= (KafkaMessage &&msg)
 {
 	if (this != &msg)
 	{
-		this->size_limit = msg.size_limit;
-		msg.size_limit = (size_t)-1;
+		*(ProtocolMessage *)this = std::move(msg);
 
 		kafka_parser_deinit(this->parser);
 		delete this->parser;
diff --git a/src/protocol/MySQLMessage.cc b/src/protocol/MySQLMessage.cc
index 7ca861b5..b3aedb29 100644
--- a/src/protocol/MySQLMessage.cc
+++ b/src/protocol/MySQLMessage.cc
@@ -22,6 +22,7 @@
 #include <errno.h>
 #include <string>
 #include <openssl/sha.h>
+#include <utility>
 #include "MySQLMessage.h"
 #include "mysql_types.h"
 
@@ -41,11 +42,9 @@ MySQLMessage::~MySQLMessage()
 	}
 }
 
-MySQLMessage::MySQLMessage(MySQLMessage&& move)
+MySQLMessage::MySQLMessage(MySQLMessage&& move) :
+	ProtocolMessage(std::move(move))
 {
-	this->size_limit = move.size_limit;
-	move.size_limit = (size_t)-1;
-
 	parser_ = move.parser_;
 	stream_ = move.stream_;
 	seqid_ = move.seqid_;
@@ -61,8 +60,7 @@ MySQLMessage& MySQLMessage::operator= (MySQLMessage&& move)
 {
 	if (this != &move)
 	{
-		this->size_limit = move.size_limit;
-		move.size_limit = (size_t)-1;
+		*(ProtocolMessage *)this = std::move(move);
 
 		mysql_parser_deinit(parser_);
 		mysql_stream_deinit(stream_);
diff --git a/src/protocol/ProtocolMessage.h b/src/protocol/ProtocolMessage.h
index a51609f3..d0ca9431 100644
--- a/src/protocol/ProtocolMessage.h
+++ b/src/protocol/ProtocolMessage.h
@@ -61,11 +61,52 @@ public:
 	void set_size_limit(size_t limit) { this->size_limit = limit; }
 	size_t get_size_limit() const { return this->size_limit; }
 
+public:
+	class Attachment
+	{
+	public:
+		virtual ~Attachment() { }
+	};
+
+	void set_attachment(Attachment *att) { this->attachment = att; }
+	Attachment *get_attachment() const { return this->attachment; }
+
 protected:
 	size_t size_limit;
 
+private:
+	Attachment *attachment;
+
 public:
-	ProtocolMessage() { this->size_limit = (size_t)-1; }
+	ProtocolMessage()
+	{
+		this->size_limit = (size_t)-1;
+		this->attachment = NULL;
+	}
+
+	virtual ~ProtocolMessage() { delete this->attachment; }
+
+public:
+	ProtocolMessage(ProtocolMessage&& msg)
+	{
+		this->size_limit = msg.size_limit;
+		msg.size_limit = (size_t)-1;
+		this->attachment = msg.attachment;
+		msg.attachment = NULL;
+	}
+
+	ProtocolMessage& operator = (ProtocolMessage&& msg)
+	{
+		if (&msg != this)
+		{
+			this->size_limit = msg.size_limit;
+			msg.size_limit = (size_t)-1;
+			this->attachment = msg.attachment;
+			msg.attachment = NULL;
+		}
+
+		return *this;
+	}
 };
 
 }
diff --git a/src/protocol/RedisMessage.cc b/src/protocol/RedisMessage.cc
index 20e1f839..254d69a0 100644
--- a/src/protocol/RedisMessage.cc
+++ b/src/protocol/RedisMessage.cc
@@ -485,11 +485,9 @@ std::string RedisValue::debug_string() const
 	return ret;
 }
 
-RedisMessage::RedisMessage(RedisMessage&& move)
+RedisMessage::RedisMessage(RedisMessage&& move) :
+	ProtocolMessage(std::move(move))
 {
-	this->size_limit = move.size_limit;
-	move.size_limit = (size_t)-1;
-
 	parser_ = move.parser_;
 	stream_ = move.stream_;
 	cur_size_ = move.cur_size_;
@@ -503,8 +501,7 @@ RedisMessage& RedisMessage::operator= (RedisMessage &&move)
 {
 	if (this != &move)
 	{
-		this->size_limit = move.size_limit;
-		move.size_limit = (size_t)-1;
+		*(ProtocolMessage *)this = std::move(move);
 
 		redis_parser_deinit(parser_);
 		delete parser_;
diff --git a/tutorial/tutorial-10-user_defined_protocol/message.cc b/tutorial/tutorial-10-user_defined_protocol/message.cc
index 644ec22f..c99fca22 100644
--- a/tutorial/tutorial-10-user_defined_protocol/message.cc
+++ b/tutorial/tutorial-10-user_defined_protocol/message.cc
@@ -21,6 +21,7 @@
 #include <string.h>
 #include <stdint.h>
 #include <arpa/inet.h>
+#include <utility>
 #include "message.h"
 
 namespace protocol
@@ -106,11 +107,9 @@ int TutorialMessage::set_message_body(const void *body, size_t size)
 	return 0;
 }
 
-TutorialMessage::TutorialMessage(TutorialMessage&& msg)
+TutorialMessage::TutorialMessage(TutorialMessage&& msg) :
+	ProtocolMessage(std::move(msg))
 {
-	this->size_limit = msg.size_limit;
-	msg.size_limit = (size_t)-1;
-
 	memcpy(this->head, msg.head, 4);
 	this->head_received = msg.head_received;
 	this->body = msg.body;
@@ -126,8 +125,7 @@ TutorialMessage& TutorialMessage::operator = (TutorialMessage&& msg)
 {
 	if (&msg != this)
 	{
-		this->size_limit = msg.size_limit;
-		msg.size_limit = (size_t)-1;
+		*(ProtocolMessage *)this = std::move(msg);
 
 		memcpy(this->head, msg.head, 4);
 		this->head_received = msg.head_received;