Java网络编程技术-02

第2章TCP协议网络编程12.1Socket通信在Java中，基于TCP协议实现网络通信的类有两个：1.在客户端的Socket类2.在效劳器端的ServerSocket类基于TCP协议实现网络通信连接过程：在效劳器端通过指定一个用来等待的连接的端口号创立一个ServerSocket实例。调用ServerSocket类的accept方法使效劳器处于阻塞状态，等待用户请求。在客户端通过规定一个主机和端口号创立一个socket实例，连到效劳器上。2

构造方法：

publicSocket()publicSocket(String

host,int

port)publicSocket(InetAddress

address,int

port)publicSocket(InetAddress

address,int

port,InetAddress

localAddr,int

localPort)

在JDK1.1以前，Socket类可同时用于TCP/UDP通信：publicSocket(String

host,int

port,boolean

stream)

publicSocket(InetAddress

host,int

port,boolean

stream)这些方法都将抛出异常IOException，程序中需要捕获处理。Socket

类3

输入/输出流管理publicInputStreamgetInputStream()publicvoidshutdownInput()publicOutputStreamgetOutputStream()publicvoidshutdownOutput()这些方法都将抛出例外IOException，程序中需要捕获处理。

关闭Socketpublicvoidclose()throwsIOException

设置/获取Socket数据publicInetAddressgetInetAddress()publicintgetPort()publicvoidsetSoTimeout(int

timeout)….这些方法都将抛出例外SocketException，程序中需要捕获处理。Socket类的主要方法4构造方法：publicServerSocket(int

port)publicServerSocket(int

port,int

backlog)：支持指定数目的连接publicServerSocket(int

port,int

backlog,InetAddress

bindAddr)这些方法都将抛出例外IOException，程序中需要捕获处理。ServerSocket类5ServerSocket类主要方法publicSocketaccept()：等待客户端的连接publicvoidclose()：关闭SocketpublicInetAddressgetInetAddress()、publicintgetLocalPort()，…publicvoidsetSoTimeout(int

timeout)，…这些方法都将抛出例外SocketException，程序中需要捕获处理。6无论一个Socket通信程序的功能多么齐全、程序多么复杂，其根本结构都是一样的，都包括以下四个根本步骤：1、在客户方和效劳器方创立Socket/ServerSocket。2、翻开连接到Socket的输入/输出流。3、利用输入/输出流，按照一定的协议对Socket进行读/写操作。4、关闭输入/输出流和Socket。通常，程序员的主要工作是针对所要完成的功能在第3步进行编程，第1、2、4步对所有的通信程序来说几乎都是一样的。7ServerServerSocket(port#)Socketsocket=ServerSocket.accept()接收连接OutputStreamInputStreamCloseSocketClientSocket(host,port#)与服务器建立连接OutputStreamInputStreamCloseSocketsocket81、建立Socket在客户端：try{Socketclient=newSocket(host,4444);}catch(IOExceptione){}在效劳器端：try{ServerSocketserver=newServerSocket(4444);}catch(IOExceptione){}Socketsocket=null;try{socket=server.accept();//等待客户端连接}catch(IOExceptione){}92、在客户端和效劳器端同时翻开输入/输出流类Socket提供了方法getInputStream()和getOutputStream()来得到Socket对应的输入/输出流以进行数据读写操作，它们分别返回InputStream对象和OutputStream对象。为了便于读写数据，应在返回的输入/输出流对象上建立过滤流，如DataInputStram/DataOutputStram、BufferedInputStream/BufferedOutputStream、PrintStream；InputStreamReader/OutputStreamWriter、BufferedReader/BufferedWriter、PrintWriter等。BufferedReader=newBufferedReader(newInputStreamReader(socket.getInputStream()));BufferedWriter=newBufferedWriter(newInputStreamWriter(socket.getOutputStream()));3、关闭输入/输出流和Socket在客户端和效劳器端分别关闭输入/输出流和Socket：先关闭所有相关的输入/输出流，在关闭Socket。10创建服务器(端口号)定义数据成员服务器等待网络连接建立socket流发送谈话信息接收用户谈话信息创建Socket实例定义数据成员建立socket流发送谈话信息接收服务器谈话信息关闭流accept()44444444结束谈话(Bye.)结束谈话(Bye.)关闭流服务器端客户端11SingleTalkClient.java看看这个谈话程序的运行效果：2、客户端SingleTalkServer.java1、效劳器端12简单的Client/Server在本地机器上测试网络程序用缭绕地址Socketsocket=newSocket(“”,4444);建立socket连接后，还应该建立输入输出数据流。要控制好输入/输出流和Socket关闭的时间。如果网络的一端已经关闭，另一端读到null。在运行时，效劳器端程序一般应先行启动。13Server1(1111)client(2222)Server2(2222)client(1111)Server解决方案一：在一台计算机上一次启动多个效劳器程序，只要端口号不同。myserver1<-------->myclient1myserver2<-------->myclient2支持多Client14解决方案二：将效劳器写成多线程的，不同的处理线程为不同的客户效劳。主线程只负责循环等待，处理线程负责网络连接，接收客户输入的信息。//主线程while(true){acceptaconnection;createathreadtodealwiththeclient;}endwhileServerclient1client2serverthread2serverthread1……15serverSocket=newServerSocket(4444);while(listening){Socketsocket;socket=serverSocket.accept();//程序将在此等候客户端的连接newMultiTalkServerThread(socket,clientNumber).start();clientNumber++;//记录客户数目}serverSocket.close();classMultiTalkServerThreadextendsThread{publicMultiTalkServerThread(Socketsocket,intclientNumber){this.socket=socket;this.clientNumber=clientNumber+1;}publicvoidrun(){…}}16客户1客户2服务器线程1()线程2()MultiTalkServer.java17Client之间通过Server通信可以在效劳器端将与各客户进行通信的Socket和线程管理起来，从而各客户之间可以在效劳器端的协助下进行通信。服务器(4444)acceptsocket客户2IP1client1线程1客户1IP2client2线程2182.2TCP网络编程案例〔1〕网络版的hello，world！程序。〔2〕简单的多人聊天(群聊)程序〔3〕GUI界面〔4〕有GUI界面的简单聊天程序〔5〕多线程实现有GUI界面的简单聊天程序〔6〕有GUI界面的简单的多人聊天聊天程序19.*;ServerSoket类构造方法:ServerSocket(intport)方法:Socketaccept();Socket类构造方法：Socket(Stringhost,intport);方法：InputStereamgetInputStream();OutputStreamgetOutputStream();20java.io.*;DataInputStream类构造方法：DataInputStream(InputStreamins);方法：StringreadUTF();DataOutputStream类构造方法：DataOutputStream(OutputStreamins)方法：voidwriteUTF();21〔1〕网络版的hello，world！程序

1〕Serverimportjava.io.*;import.*;public

classmyServer{public

static

voidmain(String[]args)throwsIOException{ServerSockets=newServerSocket(8888);Socketss=s.accept();OutputStreamos=ss.getOutputStream();DataOutputStreamdataout=newDataOutputStream(os);dataout.writeUTF("hello,world!");dataout.close();s.close();ss.close();}}222〕Clientimportjava.io.*;import.*;public

classclient{public

static

voidmain(String[]args)throwsIOException{Sockets=newSocket("",8888);InputStreamin=s.getInputStream();DataInputStreamdataIn=newDataInputStream(in);System.out.println(dataIn.readUTF());}}23〔2〕简单的多人聊天〔群聊〕程序

1〕Serverimportjava.io.*;import.*;importjava.util.*;public

classmyServer{public

staticArrayList<Socket>socketlist=newArrayList<Socket>();public

static

voidmain(String[]args)throwsIOException{ServerSocketss=newServerSocket(9999);while(true){Sockets=ss.accept();socketlist.add(s);Threadt=newThread(newserverThread(s));t.start();}}}242〕Server多线程类importjava.io.*;import.*;import

java.util.*;public

classmyServerThreadimplementsRunnable{Sockets=null;DataInputStreamdatain=null;DataOutputStreamdataout=null;publicmyServerThread(Sockets)throwsIOException{this.s=s;datain=newDataInputStream(s.getInputStream());}public

voidrun(){try{Stringc=null;while((c=readFromClient())!=null){25

for(Sockets:myServer.socketList){dataout=newDataOutputStream(s.getOutputStream());dataout.writeUTF(c);}}}catch(IOExceptione){}}privateStringreadFromClient(){try{returndatain.readUTF();}catch(IOExceptione){myServer.socketList.remove(s);}return

null;}}26３〕Clientimportjava.io.*;import.*;public

classmyClient{public

static

voidmain(String[]args)throwsIOException{Sockets=newSocket("",7000);myClientThreadct=newmyClientThread(s);Threadt=newThread(ct);t.start();DataOutputStreamdataout=newDataOutputStream(s.getOutputStream());Stringline=null;InputStreamReaderir=newInputStreamReader(System.in);BufferedReaderbr=newBufferedReader(ir);while((line=br.readLine())!=null){dataout.writeUTF(line);}}}274〕Client多线程类importjava.io.*;import.*;public

classmyClientThreadimplementsRunnable{Sockets=null;DataInputStreamdatain=null;publicmyClientThread(Socketss)throwsIOException{s=ss;datain=newDataInputStream(s.getInputStream());}28public

voidrun(){try{Stringcontent=null;while((content=datain.readUTF())!=null){System.out.println(content);}}catch(Exceptionex){}}}29〔3〕GUI界面public

classGUI{public

static

voidmain(String[]args){newmyGUI("hello!");}}30importjava.awt.*;import.*;public

class

myGUI

extendsFrame{Panelp1,p2;Buttonbs,bl,bx;TextAreat1;Labell1,l2;TextFieldtt1,tt2;publicmyGUI(Strings){super(s);p1=newPanel();p2=newPanel();t1=newTextArea(12,75);l1=newLabel("消息:");l2=newLabel("昵称:");tt1=newTextField("那你就去吧，别让妖精迷住你",36);tt2=newTextField("八戒",6);bs=newButton("发送");bl=newButton("连接");31addWindowListener(newWindowAdapter(){public

voidwindowClosing(WindowEvente){System.exit(0);}});setLayout(newFlowLayout());p1.setLayout(newBorderLayout());p1.add(t1);add(p1);p2.setLayout(newFlowLayout());p2.add(bl);p2.add(l2);p2.add(tt2);p2.add(l1);p2.add(tt1);p2.add(bs);add(p2);setBounds(100,100,600,280);setVisible(true);}}32〔4〕有GUI界面的简单聊天程序

1〕Serverpublic

classmyServer{public

static

voidmain(String[]args){newsFrame("ChatroomSever");}}33importjavax.swing.*;import.*;importjava.io.*;import.*;importjava.awt.*;public

class

sFrame

extendsJFrame{ServerSocketserver=null;Sockets=null;DataInputStreamdataIn=null;DataOutputStreamdataout=null;Panelp1,p2;Buttonbs,bl,bb;TextAreat1;TextFieldt2;34publicsFrame(Stringss){super(ss);p1=newPanel();p2=newPanel();t1=newTextArea();bb=newButton("接收消息");t2=newTextField("大师兄,我去捉妖精吧!",36);bs=newButton("发送");bl=newButton("启动");bl.addActionListener(newbll());bs.addActionListener(newbss());bb.addActionListener(newbbb());addWindowListener(newww());setLayout(newFlowLayout());p1.add(t1);add(p1);p2.setLayout(newFlowLayout());p2.add(bl);p2.add(bb);p2.add(t2);p2.add(bs);add(p2);setBounds(100,100,460,260);setVisible(true);}35classbllimplementsActionListener{public

voidactionPerformed(ActionEvente){try{server=newServerSocket(5000);s=server.accept();dataIn=newDataInputStream(s.getInputStream());dataout=newDataOutputStream(s.getOutputStream());}catch(Exceptione1){}}}classbssimplementsActionListener{public

voidactionPerformed(ActionEvente){

try{dataout.writeUTF("八戒说:"+t2.getText());t1.append("八戒说:"+t2.getText()+"\n");}36catch(IOExceptione1){}}}classbbbimplementsActionListener{public

voidactionPerformed(ActionEvente){

try{t1.append(dataIn.readUTF()+"\n");}catch(IOExceptiongg){}}}classwwextendsWindowAdapter{public

voidwindowClosing(WindowEventee){System.exit(0);}}}372〕Clientpublic

classmyClient{public

static

voidmain(String[]args){newcFrame("ChatroomClient");}}38importjava.awt.*;import.*;importjava.io.*;import.*;class

cFrame

extendsFrame{Sockets=null;DataInputStreamdataIn=null;DataOutputStreamdataout=null;Panelp1,p2;Buttonbs,bl,bb;TextAreat1;TextFieldt2;cFrame(Stringss){super(ss);p1=newPanel();p2=newPanel();t1=newTextArea();bb=newButton("接收消息");t2=newTextField("那你就去吧,别让妖精迷住!",36);bs=newButton("发送");bl=newButton("连接");bl.addActionListener(newbll());bs.addActionListener(newbss());bb.addActionListener(newbbb());addWindowListener(newww());setLayout(newFlowLayout());39p1.setLayout(newBorderLayout());p1.add(t1);add(p1);p2.setLayout(newFlowLayout());p2.add(bl);p2.add(bb);p2.add(t2);p2.add(bs);add(p2);setBounds(100,100,460,260);setVisible(true);}classbllimplementsActionListener{public

voidactionPerformed(ActionEvente){try{s=newSocket("localhost",5000);dataIn=newDataInputStream(s.getInputStream());dataout=newDataOutputStream(s.getOutputStream());}catch(IOExceptiongg){}}}40classbssimplementsActionListener{public

voidactionPerformed(ActionEvente){try{dataout.writeUTF("悟空说:"+t2.getText());t1.append("悟空说:"+t2.getText()+"\n");}catch(IOExceptione1){}}}classbbbimplementsActionListener{public

voidactionPerformed(ActionEvente){try{t1.append(dataIn.readUTF()+"\n");}catch(IOExceptiongg){}}}classwwextendsWindowAdapter{public

voidwindowClosing(WindowEventee){System.exit(0);}}}41〔5〕多线程实现有GUI界面的简单聊天程序

1〕Serverpublic

classmyServer{public

static

voidmain(String[]args){newsFrame("ChatroomSever");}}42importjavax.swing.*;import.*;importjava.io.*;import.*;importjava.awt.*;publicclasssFrameextendsJFrame{ ServerSocketserver=null; Sockets=null; DataInputStreamdataIn=null; DataOutputStreamdataout=null; Panelp1,p2; Buttonbs,bl,bb; TextAreat1; TextFieldt2;

43publicsFrame(Stringss) { super(ss); p1=newPanel(); p2=newPanel(); t1=newTextArea(); bb=newButton("接收消息"); t2=newTextField("大师兄,我去捉妖精吧!",36); bs=newButton("发送"); bl=newButton("启动"); bl.addActionListener(newbll()); bs.addActionListener(newbss()); bb.addActionListener(newbbb()); addWindowListener(newww()); setLayout(newFlowLayout()); p1.add(t1); add(p1); p2.setLayout(newFlowLayout()); p2.add(bl); p2.add(bb); p2.add(t2); p2.add(bs); add(p2); setBounds(100,100,460,260); setVisible(true); }

44classbllimplementsActionListener { publicvoidactionPerformed(ActionEvente) {

try { server=newServerSocket(5000); s=server.accept(); dataIn=newDataInputStream(s.getInputStream()); dataout=newDataOutputStream(s.getOutputStream()); newtt().start(); } catch(Exceptione1){} } } classbssimplementsActionListener { publicvoidactionPerformed(ActionEvente) { try { dataout.writeUTF("八戒说:"+t2.getText()); t1.append("八戒说:"+t2.getText()+"\n"); } catch(IOExceptione1){} } }45 classbbbimplementsActionListener { publicvoidactionPerformed(ActionEvente) { try { t1.append(dataIn.readUTF()+"\n"); } catch(IOExceptiongg){} } } classwwextendsWindowAdapter { publicvoidwindowClosing(WindowEventee) { System.exit(0); } } classttextendsThread { publicvoidrun() { while(true) { try { t1.append(dataIn.readUTF()+"\n"); } catch(IOExceptiongg){} } } }}462〕Clientpublic

classmyClient{public

static

voidmain(String[]args){newcFrame("ChatroomClient");}}47〔6〕有GUI界面的简单的多人聊天聊天程序

1〕Serverimport.*;importjava.io.*;importjava.util.*;public

classmyMultiServer{public

staticArrayList<Socket>socketList=newArrayList<Socket>();public

static

voidmain(String[]args)throwsIOException{ServerSocketss=newServerSocket(7000);Sockets=null;while(true){s=ss.accept();socketList.add(s);newThread(newserverThread(s)).start();}}}48importjava.io.*;import.*;import

java.util.*;public

classserverThreadimplementsRunnable{Sockets=null;DataInputStreamdatain=null;DataOutputStreamdataout=null;publicserverThread(Sockets)throwsIOException{this.s=s;datain=newDataInputStream(s.getInputStream());}public

voidrun(){try{Stringc=null;while((c=readFromClient())!=null){for(Sockets:myMultiServer.socketList){49dataout=newDataOutputStream(s.getOutputStream());dataout.writeUTF(c);}}}catch(IOExceptione){}}privateStringreadFromClient(){try{returndatain.readUTF();}catch(IOExceptione){myMultiServer.socketList.remove(s);}return

null;}}502〕Clientpublic

classmyClient{public

static

voidmain(String[]args){newmyClientFrame("chatroom");}}51importjava.awt.*;import.*;importjava.io.*;import.*;class

cFrame

extendsFrame{Sockets=null;DataInputStreamdataIn=null;DataOutputStreamdataout=null;Panelp1,p2;Buttonbs,bl,bb;TextAreat1;TextFieldt2;52cFrame(Stringss){super(ss);p1=newPanel();p2=newPanel();t1=newTextArea();bb=newButton("接收消息");t2=newTextField("那你就去吧,别让妖精迷住!",36);bs=newButton("发送");bl=newButton("连接");bl.addActionListener(newbll());bs.addActionListener(newbss());bb.addActionListener(newbbb());addWindowListener(newww());setLayout(newFlowLayout());p1.setLayout(newBorderLayout());p1.add(t1);add(p1);p2.setLayout(newFlowLayout());p2.add(bl);p2.add(bb);p2.add(t2);p2.add(bs);add(p2);setBounds(100,100,460,260);setVisible(true);}53classbllimplementsActionListener{public

voidactionPerformed(ActionEvente){try{s=newSocket("localhost",5000);dataIn=newDataInputStream(s.getInputStream());dataout=newDataOutputStream(s.getOutputStream());newtt().start();}catch(IOExceptiongg){}}}classbssimplementsActionListener{public

voidactionPerformed(ActionEvente){try{dataout.writeUTF("悟空说:"+t2.getText());t1.append("悟空说:"+t2.getText()