Advanced Network Programming
Jan 22, 2016
Advanced Network Programming. Ren Jiansi [email protected]. 2.4 套接口类（ Socket 、 ServerSocket ）概述 - PowerPoint PPT Presentation
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2.4 套接口类（ Socket 、 ServerSocket ）概述 套接口是网络协议传输层提供的接口。套接
口是进程之间通信的抽象连接点。它封装了端口、主机地址、传输层通信协议三方面内涵（见图3 ）。两个网络进程采用套接口方式通信时，两进程扮演的角色不同，它们使用的套接口也不同。主动请求服务的一方叫客户 , 它使用客户建立的套接口 Socket ，通过它主动与对方连接；服务者等待接收客户服务请求，提供服务，返回结果，它使用服务者套接口 ServerSocket.
用户目前可以使用的两种套接口，即流套接口和数据报套接口。流套接口提供了双向的、有序的、无重复并且无记录边界的数据流服务。 TCP 即是一种流套接口协议；数据报套接口支持
双向的数据流，但并不保证是可靠、有序、无重复的，也就是说，一个以数据报套接口接收的信息的进程有可能发现信息重复了，或者和发出的顺序不同。数据报套接口的一个重要特点是它保留了记录边界。 UDP 是数据报套接口协议。
每一进程运行在该主机的一个对外开放的端口上。主机地址用其 IP 地址或域名地址表示（见图 3 ）。一个端口与使用该端口的进程是对应的。端口常以整数编号，作为服务者可选择一个端口号，网络的客户以服务者主机和服务者选择的端口号与服务者连接。一些端口号是网络服务约定的，如 80 是 WWW 服务的缺省端口号。
图 3 基于 Socket 的点对点通信
A simple server (simplified code) // SimpleServer.java: a simple server programimport java.net.*;import java.io.*;public class SimpleServer { public static void main(String args[]) throws IOException { // Register service on port 1234 ServerSocket s = new ServerSocket(1234); Socket s1=s.accept(); // Wait and accept a connection // Get a communication stream associated with the socket OutputStream s1out = s1.getOutputStream(); DataOutputStream dos = new DataOutputStream (s1out); // Send a string! dos.writeUTF("Hi there"); // Close the connection dos.close(); s1out.close(); s1.close(); }}
A simple client (simplified code) // SimpleClient.java: a simple client programimport java.net.*;import java.io.*;public class SimpleClient { public static void main(String args[]) throws IOException { // Open your connection to a server, at port 1234 Socket s1 = new Socket("muu.oz.au",1234); // Get an input file handle from the socket and read the inpu
t InputStream s1In = s1.getInputStream(); DataInputStream dis = new DataInputStream(s1In); String st = new String (dis.readUTF()); System.out.println(st); // When done, just close the connection and exit dis.close(); s1In.close(); s1.close(); }}
1. 套接口类 (Socket)
（ 1 ）构造方法1 ） Socket(String host, int port) throws Unknown
HostException,IOException
构造一个流套接口（即 Socket 对象），利用TCP 协议将其连接至特定主机 host 的特定端口port 上。
2 ） Socket(String host,int port,boolean stream)
构造一个套接口，而此套接口是流套接口( 或 TCP 协议 ) 还是数据报（ datagram 或 UDP协议）套接口，则是由最后一个参数 stream 决定的。通信对方由主机名 host 和端口 port 来确定。
3 ） Socket(InetAddress address,int port)
构造一个流套接口，并把它连接到特定 IP 地址 address 的主机和特定端口 port 上。
4 ） Socket(InetAddress address,int port boolean stream)
构造一个套接口，此套接口是流套接口还是数据报（ datagram ）套接口，则是由最后一个参数 stream 决定的。通信对方由其主机 IP 地址address 和端口 port 确定。
（ 2 ）套接口类提供的主要方法有：1 ） InetAddress getInetAddress()
返回该套接口（ Socket ）所连接的 IP 地址。
2 ） int getPort()
返回该套接口（ Socket ）所连接的端口。3 ） sychronized void close() throws IOException
关闭套接口 4)InputStream getInputStream()
throws IOExcepiton
获得与套接口绑定的数据输入流对象。5) InputStream getOutputStream()
throws IOException
获得与套接口绑定的数据输出流对象。2. 服务者套接口类（ ServerSocket ）
（ 1 ）构造方法1 ） ServerSocket(int port) throws IOException
在指定的端口上构造一个服务者套接口，即构造一个 ServerSocket 实体对象。
2 ） ServerSocket(int port ， int count)
构造一个服务者套接口，即构造一个 ServerSocket 实体对象，并且该对象是与指定的当地端口绑定。此外，可以对它进行监听。用户也可以通过将 port 设为 0 来将该对象与一个匿名端口相连接。
参数： count 容许等待对该 ServerSocket 对象的连接的个数。
（ 2 ）服务者套接口类提供的主要方法：1 ） Socket accept() throws IOException
服务者等待连接，该方法将阻塞当前服务线程，直到连接到来。该方法返回一个新的套接口类对象，通过该对象，与客户套接口进行通信。
2 ） void close() throws IOException
关闭套接口。3 使用 TCP 协议的 Socket 网络编程1. 基于客户 / 服务器方式的一对一的 Socket 通信 TCP 是一种可靠的、基于连接的网络协议。
网络上的两进程采用 Socket 方式通信时，客户与服务器都必须建立各自的 Socket ，其中服务器构
图 4 服务方、客户间的通信流程图
建 ServerSocket 对象，并侦听来自网络的客户连接请求，另一方作为客户，通过 Socket 向网络上的服务器发送连接请求。图 4 描述基于连接的服务者、客户程序流程图。
图 5 是服务方类 TcpServer 不完全规范的 UML 模型简图。它描述了类 TcpServer 继承了 Object 类（可默认），以及它依赖的类，如： ServerSocket 、 Socket 、 DataInputStream 、 InputStream 、 IOException 、 OutputStream 、 PrintStream 等，其中主要的是 java.net 包的 Socket 、 ServerSocket 类。
图 5 服务方 UML 模型简图
例 7 利用 Socket 实现服务方和客户一对一的通信。
（ 1 ）服务方源程序package TcpServer;
import java.io.*;
import java.net.*;
public class TcpServer
{
static public void main(String args[])
throws IOException{
ServerSocket svrsoc=null;
Socket soc=null;
InputStream is=null; OutputStream os=null; DataInputStream in=null; PrintStream out=null; try{ svrsoc=new ServerSocket(8000); soc=svrsoc.accept(); is=soc.getInputStream(); in=new DataInputStream(is); os=soc.getOutputStream(); out=new PrintStream(os); InetAddress clientIP=soc.getInetAddress();
System.out.println("Client's IP address:"+ clientIP);
int port; port=soc.getPort(); System.out.println("Client's port:"+port); out.println("Welcome!..."); String str=in.readLine(); while(!str.equals("quit")){ System.out.println("Client said:"+str); str=in.readLine(); } System.out.println("Client want to leave."); }
catch(Exception e) {
System.out.println("Error:"+e);
}
finally{
is.close();
os.close();
soc.close();
System.exit(0);
}
}}
（ 2 ）客户方源程序
图 1-6 客户方 UML 模型简图
图 6 描述了客户方不完全规范的 UML 模型简图 。 它 描 述 了 类 TcpServer 继 承 了 Object 类（可默认），以及它依赖的类。代码如下：
import java.net.*;
import java.io.*;
public class TcpClient{
static public void main(String args[])
throws IOException{
Socket soc=null;
InputStream is=null;
OutputStream os=null;
DataInputStream in=null; PrintStream out=null; String strin=null; try{soc=new Socket("localhost",8000); System.out.println("Connecting to the Server..."); is=soc.getInputStream(); os=soc.getOutputStream(); in=new DataInputStream(is); out=new PrintStream(os); strin=in.readLine();
System.out.println("Server said:"+strin);
byte bmsg[] = new byte[20];
System.in.read(bmsg);
String msg=new String(bmsg,0);
msg=msg.trim();
while(!msg.equals("quit")){
out.println(msg);
System.in.read(bmsg);
msg=new String(bmsg,0);
msg=msg.trim();
}
out.println(msg); } catch (Exception e) { System.out.println("Error: "+e); } finally{ is.close(); os.close(); soc.close(); System.exit(0); } }}
服务器端运行结果如图 7 所示：
图 7 服务器端运行结果
客户端运行结果如图 8 所示：
图 8 客户端运行结果
2. 综合示例：基于浏览器 / 服务器方式的网络聊天室
例 8 如果聊天室有 n 个网友在聊天，每个网友聊天时其他网友都“看到“聊的内容。
ChatServer 的运行结构如图 1-9 所示。该例涉及到线程、小应用程序、 Socket 等多方面知识。
图 9 ChatServer 的运行结构 ( 下页 )
(1) 聊天服务者 ChatServer 实现源程序如下：import java.net.*;
import java.io.*;
import java.util.*;
public class ChatServer {
public static void main(String args[])
{
ServerSocket socket=null;
Vector m_threads=new Vector();
System.out.println("listen...");
try
{ socket=new ServerSocket(5555);} catch(Exception e) { System.out.println( "new ServerSocket()failed!"); return; } try { int nid=0; while(true) { Socket s=socket.accept();
System.out.println("accepted");
ServerThread st=new ServerThread
(s,m_threads);
st.setID(nid++);
m_threads.addElement(st);
new Thread(st). start();
for(int i=0;i<m_threads.size();i++)
{ ServerThread st1=
(ServerThread)m_threads.elementAt(i);
st1.write("<#>welcome "+st.getID()+" to
enter chatroom!");
}
System.out.println("Listen again...");
}
}
catch(Exception e)
{ System.out.println("Server is down...");}
}
}
class ServerThread implements Runnable
{ Vector m_threads;
Socket m_socket=null;
DataInputStream m_in=null;
DataOutputStream m_out=null;
int m_nid;
public ServerThread(Socket s,Vector threads)
{
m_socket=s;
m_threads=threads;
try
{
m_in=new DataInputStream
(m_socket.getInputStream());
m_out=new DataOutputStream (m_socket.getOutputStream()); } catch(Exception e) {} } public void run() { System.out.println("thread is running"); try { while(true)
{ String s=m_in.readUTF(); if (s==null) break; if (s.trim().equals ("leave")) for (int i=0;i<m_threads.size();i++) { ServerThread st=(ServerThread) m_threads.elementAt(i); st.write("*** "+getID()+" leave..."+"***"); } else for(int i=0;i<m_threads.size();i++) {
ServerThread st=(ServerThread)
m_threads.elementAt(i);
st.write("<"+getID()+">"+s);
}
}
}
catch(Exception e)
{ e.printStackTrace(); }
m_threads.removeElement(this);
try
{ m_socket.close();}
catch (Exception e){} } public void write (String msg) {synchronized(m_out) { try {m_out.writeUTF(msg);} catch(IOException e){} } } public int getID() {return m_nid;}
public void setID(int nid)
{m_nid=nid;}
}
(2) 聊天者 ChatApplet1 源程序/*
<APPLET
CODE=ChatApplet1.class
WIDTH=200
HEIGHT=200>
</APPLET>*/
import java.awt.*;
import java.applet.*;import java.io.*;import java.net.*;public class ChatApplet1 extends Applet implements Runnable{ TextArea m_textarea; TextField m_textfield; DataInputStream m_in; DataOutputStream m_out; public void init() { setLayout(null);
setSize(426,266); m_textarea=new TextArea(10,10); m_textfield=new TextField(); m_in=null; m_out=null; try{ URL url=getCodeBase(); InetAddress inetaddr= InetAddress.getByName(url.getHost()); Socket m_socket; System.out.println("Server:"+inetaddr+" "+url.
getHost()+" "+url.getProtocol()); m_socket=new Socket(inetaddr,5555);
m_in=new DataInputStream(m_socket.getInputStream());
m_out=new DataOutputStream(m_socket.getOutputStream());
} catch (Exception e) {System.out.println("Error:"+e);} setLayout(new BorderLayout()); add("Center",m_textarea); add("South",m_textfield); m_textarea.setEditable(false); new Thread(this).start();
} public boolean handleEvent(Event event) { String b=m_textfield.getText(); if((event.target==m_textfield)&& (event.id==Event.ACTION_EVENT)) { m_textfield.setText(""); try{ m_out.writeUTF(b); } catch(IOException e){} return true;
} else return super.handleEvent(event); } public void run() { try { while(true) { String s=m_in.readUTF(); if(s!=null) m_textarea.append(s+"\n"); } }
catch(Exception e) { m_textarea.append("Network problem
or Server down.\n"); m_textfield.setVisible(false); } } public void stop() { try {m_out.writeUTF("leave");} catch(IOException e){} } }
Socket programming with UDP
UDP: no “connection” between client and server
• no handshaking• UDP: transmitted
data may be received out of order, or lost
application viewpoint
UDP provides unreliable transfer of groups of bytes (“datagrams”)
between sockets
UDP socket identified by ：dest IP address, dest port number
- sender explicitly attaches IP address and port of destination to each pac
ket
- server must extract IP address, port of sender from received packet
Example: Java server (UDP)
import java.io.*; import java.net.*; class UDPServer { public static void main(String args[]) throws Exception { DatagramSocket serverSocket = new DatagramSocket(9876); byte[] receiveData = new byte[1024]; byte[] sendData = new byte[1024]; while(true) { DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
serverSocket.receive(receivePacket);
Createdatagram socket
at port 9876
Create space forreceived datagram
Receivedatagram
Example: Java server (UDP), cont String sentence = new String(receivePacket.getData()); InetAddress IPAddress = receivePacket.getAddress(); int port = receivePacket.getPort(); String capitalizedSentence = sentence.toUpperCase();
sendData = capitalizedSentence.getBytes(); DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, port); serverSocket.send(sendPacket); } }
}
Get IP addrport #, ofsender
Write out datagramto socket
End of while loop,loop back and wait foranother datagram
Create datagramto send to client
Example: Java client (UDP)
import java.io.*; import java.net.*; class UDPClient { public static void main(String args[]) throws Exception { BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in)); DatagramSocket clientSocket = new DatagramSocket(); InetAddress IPAddress = InetAddress.getByName("hostname"); byte[] sendData = new byte[1024]; byte[] receiveData = new byte[1024]; String sentence = inFromUser.readLine();
sendData = sentence.getBytes();
Createinput stream
Create client socket
Translate hostname to IP
address using DNS
Example: Java client (UDP), cont.
DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 9876); clientSocket.send(sendPacket); DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length); clientSocket.receive(receivePacket); String modifiedSentence = new String(receivePacket.getData()); System.out.println("FROM SERVER:" + modifiedSentence); clientSocket.close(); }
}
Create datagram with data-to-send,
length, IP addr, port
Send datagramto server
Read datagramfrom server
Socket programming with TCP
Client must contact server• server process must first be
running• server must have created
socket (door) that welcomes client’s contact
Client contacts server by:• creating client-local TCP socket• specifying IP address, port
number of server process• When client creates socket:
client TCP establishes connection to server TCP
• When contacted by client, server TCP creates new socket for server process to communicate with client– allows server to talk with
multiple clients– source port numbers use
d to distinguish clients
TCP provides reliable, in-order transfer of bytes
between client and server
application viewpoint
Example: Java client (TCP)
import java.io.*; import java.net.*; class TCPClient {
public static void main(String argv[]) throws Exception { String sentence; String modifiedSentence;
BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));
Socket clientSocket = new Socket("hostname", 6789);
DataOutputStream outToServer = new DataOutputStream(clientSocket.getOutputStream());
Createinput stream
Create client socket,
connect to server
Createoutput stream
attached to socket
Example: Java client (TCP), cont.
BufferedReader inFromServer = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
sentence = inFromUser.readLine();
outToServer.writeBytes(sentence + '\n');
modifiedSentence = inFromServer.readLine();
System.out.println("FROM SERVER: " + modifiedSentence);
clientSocket.close(); } }
Createinput stream
attached to socket
Send lineto server
Read linefrom server
Example: Java server (TCP)import java.io.*; import java.net.*;
class TCPServer {
public static void main(String argv[]) throws Exception { String clientSentence; String capitalizedSentence;
ServerSocket welcomeSocket = new ServerSocket(6789); while(true) { Socket connectionSocket = welcomeSocket.accept();
BufferedReader inFromClient = new BufferedReader(new InputStreamReader(connectionSocket.getInputStream()));
Createwelcoming socket
at port 6789
Wait, on welcomingsocket for contact
by client
Create inputstream, attached
to socket
Example: Java server (TCP), cont
DataOutputStream outToClient = new DataOutputStream(connectionSocket.getOutputStream());
clientSentence = inFromClient.readLine();
capitalizedSentence = clientSentence.toUpperCase() + '\n';
outToClient.writeBytes(capitalizedSentence); } } }
Read in linefrom socket
Create outputstream,
attached to socket
Write out lineto socket
End of while loop,loop back and wait foranother client connection
WebBrowser
import java.io.IOException;
import java.net.URL;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.event.*;
public class WebBrowser extends JFrame {
JPanel contentPane;
BorderLayout borderLayoutAll = new BorderLayout();
JLabel jLabelPrompt = new JLabel();
JPanel jPanelMain = new JPanel();
BorderLayout borderLayoutMain = new BorderLayout();
JTextField textFieldURL = new JTextField(); JEditorPane jEditorPane = new JEditorPane(); public WebBrowser() {
try {
Init();
} catch (Exception e) {
e.printStackTrace();
}
}
private void Init() throws Exception {
contentPane = (JPanel) getContentPane();
contentPane.setLayout(borderLayoutAll);
jPanelMain.setLayout
(borderLayoutMain);
jLabelPrompt.setText(" 请输入 URL");
textFieldURL.setText("");
textFieldURL.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(ActionEvent e) { textFieldURL_actionPerformed(e);
}});
jEditorPane.setEditable(false); jEditorPane .addHyperlinkList
ener(new javax.swing.event.HyperlinkListener() {
public void hyperlinkUpdate(HyperlinkEvent e) {
jEditorPane_hyperlinkUpdate(e);}
});JScrollPane scrollPane = new JScrollPane();scrollPane.getViewport().add(jEditorPane);jPanelMain.add(textFieldURL, "North");jPanelMain.add(scrollPane, "Center");contentPane.add(jLabelPrompt, "North");contentPane.add(jPanelMain, "Center");enableEvents(AWTEvent.WINDOW_EVENT_MA
SK);this.setSize(new Dimension(600, 500));this.setTitle("Browser ");
this.setVisible(true);}void textFieldURL_actionPerformed(ActionEvent e) { try {jEditorPane.setPage("http://"+textFieldURL.getText());
textFieldURL.setText("http://"+textFieldURL.getText());
} catch (IOException ex){
JOptionPane msg = new JOptionPane();
JOptionPane.showMessageDialog(this, "URL 地址不正确： "
+ textFieldURL.getText(), " 输入不正确！ ", 0);
}}
void jEditorPane_hyperlinkUpdate(HyperlinkEvent e) {
if (e.getEventType() == javax.swing.event.HyperlinkEvent.EventType.ACTIVATED) {
try {
URL url = e.getURL(); jEditorPane.setPage(url); te
xtFieldURL.setText(url.toString()); } catch (IOException io) {
JOptionPane msg = new JOptionPane();
JOptionPane.showMessageDialog(this, " 打开 该链接失败！ ", " 输入不正确！ ", 0);
}}
}protected void processWindowEvent(WindowEvent e) {
super.processWindowEvent(e);if (e.getID() == WindowEvent.WINDOW_CLOSI
NG) {System.exit(0);
}}
public static void main(String[] args) { new WebBrowser();}}
chatimport java.net.*;import java.awt.*;import javax.swing.*;import java.awt.event.*;import java.util.GregorianCalendar;import javax.swing.JDialog;public class chat extends Frame implements ActionListe
ner {Label label1 = new Label(" 消息目的地址 ");TextArea input = new TextArea("", 7, 14, TextArea.SCROLLBARS_BOTH);TextArea output = new TextArea("", 8, 14, TextArea.SCROLLBARS_BOTH);
TextField IPAdd = new TextField("127.0.0.1");Button send = new Button(" 发送 ");GregorianCalendar time = new GregorianCalendar();
chat() {super("chat");setLayout(null);setLocation(168, 168);this.setSize(398, 380);this.setResizable(false); this.setBackground(new
Color(216, 216, 216));
input.setBackground(new Color(255, 255, 255));input.setFont(new Font("Times New Roma
n", Font.BOLD, 15));input.setForeground(Color.black);input.setBounds(8, 218, 388, 106);
output.setBackground(new Color(255, 255, 255));
output.setFont(new Font("Times New Roman", Font.PLAIN, 12));
output.setForeground(Color.black);output.setBounds(8, 44, 388, 166);
output.setEditable(false);
send.setFont(new Font(" 新宋体 ", Font.PLAIN, 12));
send.setLocation(136, 350);
send.setSize(120, 22);
label1.setFont(new Font(" 宋体 ", Font.PLAIN, 12));
label1.setForeground(new Color(0, 0, 192));
label1.setBounds(8, 328, 160, 16);
IPAdd.setFont(new Font(" 新宋体 ", Font.PLAIN, 12));
IPAdd.setLocation(8, 350);IPAdd.setSize(120, 19);add(input);add(label1);add(output);add(IPAdd);add(send);addWindowListener(new closeWin());send.addActionListener(this);show();
waitForData();}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == send)
sendData();
}
public static void main(String args[]) {
new chat();
}
void sendData() {
try {
String msg = input.getText();
if (msg.equals(""))
return;
input.setText("");
String ad = IPAdd.getText();
InetAddress tea = InetAddress.getLocalHost();
String asd = tea.getHostAddress(); output.append("[" + asd + "]:(" + time.
get(GregorianCalendar.YEAR)
+ "-" + time.get(GregorianCalendar.MONTH) + "-"
+ time.get(GregorianCalendar.DATE) + " "
+ time.get(GregorianCalendar.HOUR) + ":"
+ time.get(GregorianCalendar.MINUTE) + ":"
+ time.get(GregorianCalendar.SECOND) + ") " + "\n" + msg
+ "\n");
msg = "From [" + asd + "]:(" + time.get(GregorianCalendar.YEAR)
+ "-" + time.get(GregorianCalendar.MONTH) +
"-" + time.get(GregorianCalendar.DATE) + " "
+ time.get(GregorianCalendar.HOUR) + ":"
+ time.get(GregorianCalendar.MINUTE) + ":"
+ time.get(GregorianCalendar.SECOND) + ") \n" + msg;
InetAddress address = InetAddress.getByName(ad);
int len = msg.length();
byte[] message = new byte[len];
msg.getBytes(0, len, message, 0);
DatagramPacket packet = new DatagramPacket(message, len, address,5678);
DatagramSocket socket = new DatagramSocket();
socket.send(packet);
} catch (Exception e) {
}
}
void waitForData() {
try {
byte[] buffer = new byte[1024];
DatagramPacket packet = new DatagramPacket(buffer, buffer.length);
DatagramSocket socket = new DatagramSocket(5678);
while (true) {
socket.receive(packet);
String s = new String(buffer, 0, 0, packet.getLength());
output.append(s + "\n");
packet = new DatagramPacket(buffer, buffer.length);
}
} catch (Exception e) {
}
}
}
class closeWin extends WindowAdapter {
public void windowClosing(WindowEvent e) {
Frame fr = (Frame) (e.getSource());
fr.dispose();
System.exit(0);
}
}
小结 : 通信协议是通信双方的约定。 TCP/IP 协议是 Internet 网络层、传送层、应用层一系列通信协议的习惯称呼。 URL 类封装了 www 资源（ Web 页、文本文件、图形文件、声频片段等）定位协议。利用 URL 类，可以访问 www 资源。 套接口是基于传送层协议的网络进程之间通信的抽象。套接口按使用的协议不同分为面向连接的 Socket 和不连接的 Socket 。套接口的端口是定位主机上通信的网络进程。使用套接口通信的主动方叫客户，被动方叫服务者。客户和服务者利用 Socket 通信，双方的作用各不一样。客户程序利用 TCP 、请求连接的服务器地址（包括端口）建立自己的套接口，服务器利用指定的端口，建立自己的套接口，等待客户服务请求，并为服务处理结果建立新的套接口与客户连接。
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