diff --git a/net/server.go b/net/server.go
index 355fe69..806c99e 100644
--- a/net/server.go
+++ b/net/server.go
@@ -1,10 +1,8 @@
 package net
 
 import (
-	"context"
 	"fmt"
 	"net"
-	"sync"
 	"sync/atomic"
 	"time"
 
@@ -12,18 +10,24 @@ import (
 	"git.loafle.net/commons/server-go"
 )
 
-type Server struct {
-	ServerHandler ServerHandler
-
-	ctx         server.ServerCtx
-	connections sync.Map
-	stopChan    chan struct{}
-	stopWg      sync.WaitGroup
+type Server interface {
+	server.Server
 }
 
-func (s *Server) ListenAndServe() error {
-	if s.stopChan != nil {
-		return fmt.Errorf(s.serverMessage("already running. Stop it before starting it again"))
+func NewServer(serverHandler ServerHandler) Server {
+	s := &netServer{}
+	s.ServerHandler = serverHandler
+
+	return s
+}
+
+type netServer struct {
+	server.Servers
+}
+
+func (s *netServer) ListenAndServe() error {
+	if s.StopChan != nil {
+		return fmt.Errorf(s.ServerMessage("already running. Stop it before starting it again"))
 	}
 
 	var (
@@ -37,52 +41,25 @@ func (s *Server) ListenAndServe() error {
 		return err
 	}
 
-	s.ctx = s.ServerHandler.ServerCtx()
-	if nil == s.ctx {
-		return fmt.Errorf(s.serverMessage("ServerCtx is nil"))
+	s.ServerCtx = s.ServerHandler.ServerCtx()
+	if nil == s.ServerCtx {
+		return fmt.Errorf(s.ServerMessage("ServerCtx is nil"))
 	}
 
-	if err = s.ServerHandler.Init(s.ctx); nil != err {
+	if err = s.ServerHandler.Init(s.ServerCtx); nil != err {
 		return err
 	}
 
-	if listener, err = s.ServerHandler.Listener(s.ctx); nil != err {
+	if listener, err = s.ServerHandler.Listener(s.ServerCtx); nil != err {
 		return err
 	}
 
-	s.stopChan = make(chan struct{})
-	s.stopWg.Add(1)
+	s.StopChan = make(chan struct{})
+	s.StopWg.Add(1)
 	return s.handleServer(listener)
 }
 
-func (s *Server) Shutdown(ctx context.Context) error {
-	if s.stopChan == nil {
-		return fmt.Errorf(s.serverMessage("server must be started before stopping it"))
-	}
-	close(s.stopChan)
-	s.stopWg.Wait()
-
-	s.ServerHandler.Destroy(s.ctx)
-
-	s.stopChan = nil
-
-	return nil
-}
-
-func (s *Server) ConnectionSize() int {
-	var sz int
-	s.connections.Range(func(k, v interface{}) bool {
-		sz++
-		return true
-	})
-	return sz
-}
-
-func (s *Server) serverMessage(msg string) string {
-	return fmt.Sprintf("Server[%s]: %s", s.ServerHandler.GetName(), msg)
-}
-
-func (s *Server) handleServer(listener net.Listener) error {
+func (s *netServer) handleServer(listener net.Listener) error {
 	var (
 		stopping atomic.Value
 		netConn  net.Conn
@@ -94,18 +71,18 @@ func (s *Server) handleServer(listener net.Listener) error {
 			listener.Close()
 		}
 
-		s.ServerHandler.OnStop(s.ctx)
+		s.ServerHandler.OnStop(s.ServerCtx)
 
-		logging.Logger().Infof(s.serverMessage("Stopped"))
+		logging.Logger().Infof(s.ServerMessage("Stopped"))
 
-		s.stopWg.Done()
+		s.StopWg.Done()
 	}()
 
-	if err = s.ServerHandler.OnStart(s.ctx); nil != err {
+	if err = s.ServerHandler.OnStart(s.ServerCtx); nil != err {
 		return err
 	}
 
-	logging.Logger().Infof(s.serverMessage("Started"))
+	logging.Logger().Infof(s.ServerMessage("Started"))
 
 	for {
 		acceptChan := make(chan struct{})
@@ -113,14 +90,14 @@ func (s *Server) handleServer(listener net.Listener) error {
 		go func() {
 			if netConn, err = listener.Accept(); err != nil {
 				if nil == stopping.Load() {
-					logging.Logger().Errorf(s.serverMessage(fmt.Sprintf("%v", err)))
+					logging.Logger().Errorf(s.ServerMessage(fmt.Sprintf("%v", err)))
 				}
 			}
 			close(acceptChan)
 		}()
 
 		select {
-		case <-s.stopChan:
+		case <-s.StopChan:
 			stopping.Store(true)
 			listener.Close()
 			<-acceptChan
@@ -131,7 +108,7 @@ func (s *Server) handleServer(listener net.Listener) error {
 
 		if nil != err {
 			select {
-			case <-s.stopChan:
+			case <-s.StopChan:
 				return nil
 			case <-time.After(time.Second):
 			}
@@ -141,178 +118,32 @@ func (s *Server) handleServer(listener net.Listener) error {
 		if 0 < s.ServerHandler.GetConcurrency() {
 			sz := s.ConnectionSize()
 			if sz >= s.ServerHandler.GetConcurrency() {
-				logging.Logger().Warnf(s.serverMessage(fmt.Sprintf("max connections size %d, refuse", sz)))
+				logging.Logger().Warnf(s.ServerMessage(fmt.Sprintf("max connections size %d, refuse", sz)))
 				netConn.Close()
 				continue
 			}
 		}
 
-		servlet := s.ServerHandler.Servlet()
+		servlet := s.ServerHandler.(ServerHandler).Servlet()
 		if nil == servlet {
-			logging.Logger().Errorf(s.serverMessage("Servlet is nil"))
+			logging.Logger().Errorf(s.ServerMessage("Servlet is nil"))
 			continue
 		}
 
-		servletCtx := servlet.ServletCtx(s.ctx)
+		servletCtx := servlet.ServletCtx(s.ServerCtx)
 		if nil == servletCtx {
-			logging.Logger().Errorf(s.serverMessage("ServletCtx is nil"))
+			logging.Logger().Errorf(s.ServerMessage("ServletCtx is nil"))
 			continue
 		}
 
 		if err := servlet.Handshake(servletCtx, netConn); nil != err {
-			logging.Logger().Infof(s.serverMessage(fmt.Sprintf("Handshaking of Client[%s] has been failed %v", netConn.RemoteAddr(), err)))
+			logging.Logger().Infof(s.ServerMessage(fmt.Sprintf("Handshaking of Client[%s] has been failed %v", netConn.RemoteAddr(), err)))
 			continue
 		}
 
 		conn := server.NewConn(netConn, true, s.ServerHandler.GetReadBufferSize(), s.ServerHandler.GetWriteBufferSize())
 
-		s.stopWg.Add(1)
-		go s.handleConnection(servlet, servletCtx, conn)
-	}
-}
-
-func (s *Server) handleConnection(servlet Servlet, servletCtx server.ServletCtx, conn *server.Conn) {
-	addr := conn.RemoteAddr()
-
-	defer func() {
-		if nil != conn {
-			conn.Close()
-		}
-		servlet.OnDisconnect(servletCtx)
-		logging.Logger().Infof(s.serverMessage(fmt.Sprintf("Client[%s] has been disconnected", addr)))
-		s.stopWg.Done()
-	}()
-
-	logging.Logger().Infof(s.serverMessage(fmt.Sprintf("Client[%s] has been connected", addr)))
-
-	s.connections.Store(conn, true)
-	defer s.connections.Delete(conn)
-
-	servlet.OnConnect(servletCtx, conn)
-	conn.SetCloseHandler(func(code int, text string) error {
-		logging.Logger().Debugf("close")
-		return nil
-	})
-
-	stopChan := make(chan struct{})
-	servletDoneChan := make(chan struct{})
-
-	readChan := make(chan []byte, 256)
-	writeChan := make(chan []byte, 256)
-
-	readerDoneChan := make(chan struct{})
-	writerDoneChan := make(chan struct{})
-
-	go servlet.Handle(servletCtx, stopChan, servletDoneChan, readChan, writeChan)
-	go handleRead(s, conn, stopChan, readerDoneChan, readChan)
-	go handleWrite(s, conn, stopChan, writerDoneChan, writeChan)
-
-	select {
-	case <-readerDoneChan:
-		close(stopChan)
-		<-writerDoneChan
-		<-servletDoneChan
-	case <-writerDoneChan:
-		close(stopChan)
-		<-readerDoneChan
-		<-servletDoneChan
-	case <-servletDoneChan:
-		close(stopChan)
-		<-readerDoneChan
-		<-writerDoneChan
-	case <-s.stopChan:
-		close(stopChan)
-		<-readerDoneChan
-		<-writerDoneChan
-		<-servletDoneChan
-	}
-}
-
-func handleRead(s *Server, conn *server.Conn, stopChan <-chan struct{}, doneChan chan<- struct{}, readChan chan []byte) {
-	defer func() {
-		doneChan <- struct{}{}
-	}()
-
-	if 0 < s.ServerHandler.GetMaxMessageSize() {
-		conn.SetReadLimit(s.ServerHandler.GetMaxMessageSize())
-	}
-	if 0 < s.ServerHandler.GetReadTimeout() {
-		conn.SetReadDeadline(time.Now().Add(s.ServerHandler.GetReadTimeout()))
-	}
-	conn.SetPongHandler(func(string) error {
-		conn.SetReadDeadline(time.Now().Add(s.ServerHandler.GetPongTimeout()))
-		return nil
-	})
-
-	var (
-		message []byte
-		err     error
-	)
-
-	for {
-		readMessageChan := make(chan struct{})
-
-		go func() {
-			_, message, err = conn.ReadMessage()
-			close(readMessageChan)
-		}()
-
-		select {
-		case <-stopChan:
-			conn.Close()
-			<-readMessageChan
-			return
-		case <-readMessageChan:
-		}
-
-		if nil != err {
-			if server.IsUnexpectedCloseError(err, server.CloseGoingAway, server.CloseAbnormalClosure) {
-				logging.Logger().Debugf(s.serverMessage(fmt.Sprintf("Read error %v", err)))
-			}
-			return
-		}
-
-		readChan <- message
-	}
-}
-
-func handleWrite(s *Server, conn *server.Conn, stopChan <-chan struct{}, doneChan chan<- struct{}, writeChan chan []byte) {
-	defer func() {
-		doneChan <- struct{}{}
-	}()
-
-	ticker := time.NewTicker(s.ServerHandler.GetPingPeriod())
-	defer func() {
-		ticker.Stop()
-	}()
-	for {
-		select {
-		case message, ok := <-writeChan:
-			if 0 < s.ServerHandler.GetWriteTimeout() {
-				conn.SetWriteDeadline(time.Now().Add(s.ServerHandler.GetWriteTimeout()))
-			}
-
-			if !ok {
-				conn.WriteMessage(server.CloseMessage, []byte{})
-				return
-			}
-
-			w, err := conn.NextWriter(server.TextMessage)
-			if err != nil {
-				return
-			}
-			w.Write(message)
-
-			if err := w.Close(); nil != err {
-				return
-			}
-		case <-ticker.C:
-			conn.SetWriteDeadline(time.Now().Add(s.ServerHandler.GetPingTimeout()))
-			if err := conn.WriteMessage(server.PingMessage, nil); nil != err {
-				return
-			}
-		case <-stopChan:
-			return
-		}
+		s.StopWg.Add(1)
+		go s.HandleConnection(servlet, servletCtx, conn)
 	}
 }
diff --git a/server.go b/server.go
new file mode 100644
index 0000000..13efc35
--- /dev/null
+++ b/server.go
@@ -0,0 +1,200 @@
+package server
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"time"
+
+	logging "git.loafle.net/commons/logging-go"
+)
+
+type Server interface {
+	ListenAndServe() error
+	Shutdown(ctx context.Context) error
+	ConnectionSize() int
+
+	HandleConnection(servlet Servlet, servletCtx ServletCtx, conn *Conn)
+	HandleRead(conn *Conn, stopChan <-chan struct{}, doneChan chan<- struct{}, readChan chan []byte)
+	HandleWrite(conn *Conn, stopChan <-chan struct{}, doneChan chan<- struct{}, writeChan chan []byte)
+}
+
+type Servers struct {
+	ServerHandler ServerHandler
+
+	ServerCtx   ServerCtx
+	Connections sync.Map
+	StopChan    chan struct{}
+	StopWg      sync.WaitGroup
+}
+
+func (s *Servers) Shutdown(ctx context.Context) error {
+	if s.StopChan == nil {
+		return fmt.Errorf("server must be started before stopping it")
+	}
+	close(s.StopChan)
+	s.StopWg.Wait()
+
+	s.ServerHandler.Destroy(s.ServerCtx)
+
+	s.StopChan = nil
+
+	return nil
+}
+
+func (s *Servers) ConnectionSize() int {
+	var sz int
+	s.Connections.Range(func(k, v interface{}) bool {
+		sz++
+		return true
+	})
+	return sz
+}
+
+func (s *Servers) ServerMessage(msg string) string {
+	return fmt.Sprintf("Server[%s]: %s", s.ServerHandler.GetName(), msg)
+}
+
+func (s *Servers) HandleConnection(servlet Servlet, servletCtx ServletCtx, conn *Conn) {
+	addr := conn.RemoteAddr()
+
+	defer func() {
+		if nil != conn {
+			conn.Close()
+		}
+		servlet.OnDisconnect(servletCtx)
+		logging.Logger().Infof(s.ServerMessage(fmt.Sprintf("Client[%s] has been disconnected", addr)))
+		s.StopWg.Done()
+	}()
+
+	logging.Logger().Infof(s.ServerMessage(fmt.Sprintf("Client[%s] has been connected", addr)))
+
+	s.Connections.Store(conn, true)
+	defer s.Connections.Delete(conn)
+
+	servlet.OnConnect(servletCtx, conn)
+	conn.SetCloseHandler(func(code int, text string) error {
+		logging.Logger().Debugf("close")
+		return nil
+	})
+
+	stopChan := make(chan struct{})
+	servletDoneChan := make(chan struct{})
+
+	readChan := make(chan []byte)
+	writeChan := make(chan []byte)
+
+	readerDoneChan := make(chan struct{})
+	writerDoneChan := make(chan struct{})
+
+	go servlet.Handle(servletCtx, stopChan, servletDoneChan, readChan, writeChan)
+	go s.HandleRead(conn, stopChan, readerDoneChan, readChan)
+	go s.HandleWrite(conn, stopChan, writerDoneChan, writeChan)
+
+	select {
+	case <-readerDoneChan:
+		close(stopChan)
+		<-writerDoneChan
+		<-servletDoneChan
+	case <-writerDoneChan:
+		close(stopChan)
+		<-readerDoneChan
+		<-servletDoneChan
+	case <-servletDoneChan:
+		close(stopChan)
+		<-readerDoneChan
+		<-writerDoneChan
+	case <-s.StopChan:
+		close(stopChan)
+		<-readerDoneChan
+		<-writerDoneChan
+		<-servletDoneChan
+	}
+}
+
+func (s *Servers) HandleRead(conn *Conn, stopChan <-chan struct{}, doneChan chan<- struct{}, readChan chan []byte) {
+	defer func() {
+		doneChan <- struct{}{}
+	}()
+
+	if 0 < s.ServerHandler.GetMaxMessageSize() {
+		conn.SetReadLimit(s.ServerHandler.GetMaxMessageSize())
+	}
+	if 0 < s.ServerHandler.GetReadTimeout() {
+		conn.SetReadDeadline(time.Now().Add(s.ServerHandler.GetReadTimeout()))
+	}
+	conn.SetPongHandler(func(string) error {
+		conn.SetReadDeadline(time.Now().Add(s.ServerHandler.GetPongTimeout()))
+		return nil
+	})
+
+	var (
+		message []byte
+		err     error
+	)
+
+	for {
+		readMessageChan := make(chan struct{})
+
+		go func() {
+			_, message, err = conn.ReadMessage()
+			close(readMessageChan)
+		}()
+
+		select {
+		case <-s.StopChan:
+			<-readMessageChan
+			return
+		case <-readMessageChan:
+		}
+
+		if nil != err {
+			if IsUnexpectedCloseError(err, CloseGoingAway, CloseAbnormalClosure) {
+				logging.Logger().Debugf(s.ServerMessage(fmt.Sprintf("Read error %v", err)))
+			}
+			return
+		}
+
+		readChan <- message
+	}
+}
+
+func (s *Servers) HandleWrite(conn *Conn, stopChan <-chan struct{}, doneChan chan<- struct{}, writeChan chan []byte) {
+	defer func() {
+		doneChan <- struct{}{}
+	}()
+
+	ticker := time.NewTicker(s.ServerHandler.GetPingPeriod())
+	defer func() {
+		ticker.Stop()
+	}()
+	for {
+		select {
+		case message, ok := <-writeChan:
+			if 0 < s.ServerHandler.GetWriteTimeout() {
+				conn.SetWriteDeadline(time.Now().Add(s.ServerHandler.GetWriteTimeout()))
+			}
+			if !ok {
+				conn.WriteMessage(CloseMessage, []byte{})
+				return
+			}
+
+			w, err := conn.NextWriter(TextMessage)
+			if err != nil {
+				return
+			}
+			w.Write(message)
+
+			if err := w.Close(); nil != err {
+				return
+			}
+		case <-ticker.C:
+			conn.SetWriteDeadline(time.Now().Add(s.ServerHandler.GetPingTimeout()))
+			if err := conn.WriteMessage(PingMessage, nil); nil != err {
+				return
+			}
+		case <-stopChan:
+			return
+		}
+	}
+}