📄 03-套接字编程(上3).htm
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<TD>// SSServer.java<BR><BR>import java.io.*;<BR>import java.net.*;<BR>import java.util.*;<BR><BR>class SSServer<BR>{<BR> public static void main (String [] args) throws IOException<BR> { <BR> System.out.println ("Server starting...\n"); <BR><BR> // Create a server socket that listens for incoming connection<BR> // requests on port 10000.<BR><BR> ServerSocket server = new ServerSocket (10000);<BR><BR> while (true)<BR> {<BR> // Listen for incoming connection requests from client<BR> // programs, establish a connection, and return a Socket<BR> // object that represents this connection.<BR><BR> Socket s = server.accept ();<BR><BR> System.out.println ("Accepting Connection...\n");<BR><BR> // Start a thread to handle the connection.<BR><BR> new ServerThread (s).start ();<BR> }<BR> }<BR>}<BR><BR>class ServerThread extends Thread<BR>{<BR> private Socket s;<BR><BR> ServerThread (Socket s)<BR> {<BR> this.s = s;<BR> }<BR><BR> public void run ()<BR> {<BR> BufferedReader br = null;<BR> PrintWriter pw = null;<BR><BR> try<BR> {<BR> // Create an input stream reader that chains to the socket's<BR> // byte-oriented input stream. The input stream reader<BR> // converts bytes read from the socket to characters. The<BR> // conversion is based on the platform's default character<BR> // set.<BR><BR> InputStreamReader isr;<BR> isr = new InputStreamReader (s.getInputStream ());<BR><BR> // Create a buffered reader that chains to the input stream<BR> // reader. The buffered reader supplies a convenient method<BR> // for reading entire lines of text.<BR><BR> br = new BufferedReader (isr);<BR><BR> // Create a print writer that chains to the socket's byte-<BR> // oriented output stream. The print writer creates an<BR> // intermediate output stream writer that converts<BR> // characters sent to the socket to bytes. The conversion<BR> // is based on the platform's default character set.<BR><BR> pw = new PrintWriter (s.getOutputStream (), true);<BR><BR> // Create a calendar that makes it possible to obtain date<BR> // and time information.<BR><BR> Calendar c = Calendar.getInstance ();<BR><BR> // Because the client program may send multiple commands, a<BR> // loop is required. Keep looping until the client either<BR> // explicitly requests termination by sending a command<BR> // beginning with letters BYE or implicitly requests<BR> // termination by closing its output stream.<BR><BR> do<BR> {<BR> // Obtain the client program's next command.<BR><BR> String cmd = br.readLine ();<BR><BR> // Exit if client program has closed its output stream.<BR><BR> if (cmd == null)<BR> break;<BR> <BR> // Convert command to uppercase, for ease of comparison.<BR><BR> cmd = cmd.toUpperCase ();<BR><BR> // If client program sends BYE command, terminate.<BR><BR> if (cmd.startsWith ("BYE"))<BR> break;<BR><BR> // If client program sends DATE or TIME command, return<BR> // current date/time to the client program.<BR><BR> if (cmd.startsWith ("DATE") || cmd.startsWith ("TIME"))<BR> pw.println (c.getTime ().toString ());<BR><BR> // If client program sends DOM (Day Of Month) command,<BR> // return current day of month to the client program.<BR><BR> if (cmd.startsWith ("DOM"))<BR> pw.println ("" + c.get (Calendar.DAY_OF_MONTH));<BR><BR> // If client program sends DOW (Day Of Week) command,<BR> // return current weekday (as a string) to the client<BR> // program.<BR><BR> if (cmd.startsWith ("DOW"))<BR> switch (c.get (Calendar.DAY_OF_WEEK))<BR> {<BR> case Calendar.SUNDAY : pw.println ("SUNDAY");<BR> break;<BR><BR> case Calendar.MONDAY : pw.println ("MONDAY");<BR> break;<BR><BR> case Calendar.TUESDAY : pw.println ("TUESDAY");<BR> break;<BR><BR> case Calendar.WEDNESDAY: pw.println ("WEDNESDAY");<BR> break;<BR><BR> case Calendar.THURSDAY : pw.println ("THURSDAY");<BR> break;<BR><BR> case Calendar.FRIDAY : pw.println ("FRIDAY");<BR> break;<BR><BR> case Calendar.SATURDAY : pw.println ("SATURDAY");<BR> }<BR><BR> // If client program sends DOY (Day of Year) command,<BR> // return current day of year to the client program.<BR><BR> if (cmd.startsWith ("DOY"))<BR> pw.println ("" + c.get (Calendar.DAY_OF_YEAR));<BR><BR> // If client program sends PAUSE command, sleep for three<BR> // seconds.<BR> <BR> if (cmd.startsWith ("PAUSE"))<BR> try<BR> {<BR> Thread.sleep (3000);<BR> }<BR> catch (InterruptedException e)<BR> {<BR> }<BR> }<BR> while (true);<BR> {<BR> catch (IOException e)<BR> {<BR> System.out.println (e.toString ());<BR> }<BR> finally<BR> {<BR> System.out.println ("Closing Connection...\n");<BR><BR> try<BR> {<BR> if (br != null)<BR> br.close ();<BR><BR> if (pw != null)<BR> pw.close ();<BR><BR> if (s != null)<BR> s.close ();<BR> }<BR> catch (IOException e)<BR> {<BR> }<BR> }<BR> }<BR>}</TD></TR></TBODY></TABLE><BR> 运行这段程序将得到下面的输出：<BR><BR>
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<TD>Server starting...<BR>Accepting Connection...<BR>Closing Connection...</TD></TR></TBODY></TABLE><BR> SSServer的源代码声明了一对类：SSServer 和ServerThread；SSServer的main()方法创建了一个ServerSocket对象来监听端口10000上的连接请求，如果成功, SSServer进入一个无限循环中，交替调用ServerSocket的 accept() 方法来等待连接请求，同时启动后台线程处理连接（accept()返回的请求）。线程由ServerThread继承的start()方法开始，并执行ServerThread的run()方法中的代码。<BR><BR> 一旦run()方法运行，线程将创建BufferedReader, PrintWriter和 Calendar对象并进入一个循环，这个循环由读（通过BufferedReader的 readLine()）来自客户程序的一行文本开始，文本（命令）存储在cmd引用的string对象中，如果客户程序过早的关闭输出流，会发生什么呢？答案是：cmd将得不到赋值。<BR><BR> 注意必须考虑到这种情况：在服务程序正在读输入流时，客户程序关闭了输出流，如果没有对这种情况进行处理，那么程序将产生异常。<BR><BR> 一旦编译了SSServer的源代码，通过输入Java SSServer来运行程序，在开始运行SSServer后，就可以运行一个或多个SSClient程序。<br><br> </DIV> </TD> </TR> <TR> <TD class=center01> <div align="center">来源：天极网 作者：<div> </TD> <TD width="280" class=center01> <div align="center"> <font color=#0000FF><a href='chapter.php?id=387&volume=3&chapter=2'>上一页</a></font> <font color=#0000FF><a href="serialize.php?id=387">回书目</a></font> <font color=#0000FF><a href='chapter.php?id=387&volume=3&chapter=4'>下一页</a></font> </div> </TD> </TR> </TBODY></TABLE><table><tr><td width="760"> <table width="760" height="10" border="0" cellpadding="0" cellspacing="0"> <tr> <td></td> </tr> </table> <!------------ 评论 ----------------> <table width="760" border="0" cellpadding="0" cellspacing="0"> <tr> <td><iframe width="100%" id=vs frameborder=0 scrolling=no src="comment_list1.php?id=387"></iframe> </td> </tr> </table><br><script language=javascript>function CheckNetwordForm(theForm){ if("" == theForm.content.value) { alert("写两句吧~~"); theForm.content.focus(); return false; } var index; for(index=0;index<theForm.content.value.length;index++) { if(" " != theForm.content.value.charAt(index)) break; } if(index == theForm.content.value.length) { alert("写两句吧~~"); theForm.content.focus(); return false; } if (theForm.content.value.length>100){ alert("评论字数不能超过100哦"); theForm.content.focus(); return false; } return true;}</script> <!------------------ 评论 ---------------> <form name=netword method=post action="insertnetword.php" onsubmit="javascript: return CheckNetwordForm(this);"> <table width="760" border="0" cellpadding="0" cellspacing="0"> <tr> <td height="25" class="text6"> 给此书打分：<a name="1"></a> <select name="score"> <option value=5 selected>非常好</option> <option value=4>还凑合</option> <option value=3>一般吧</option> <option value=2>不太行</option> <option value=1>太差了</option> </select> 用户名： <input name="id" value=387 type="hidden" id="id"> <input name="backurl" value=/book/chapter.php?id=387&volume=3&chapter=3 type="hidden"> <input name="username" type="text" id="username" size="20" maxlength="20"> <font color="#666666">*评论字数请控制在一百字以内</font> </td> </tr> </table> <br> <textarea name="content" cols="80" rows="4" wrap="OFF" id="description"></textarea> <input type="submit" name="Submit" value="提交"> </form> </td> </tr></table></td></tr></table> <TABLE cellSpacing=0 cellPadding=0 width=760 border=0> <TBODY> <TR> <TD width="1003" height=9 background=images/t_bj01.gif><IMG height=1 src="images/ccc.gif" width=1></TD> </TR> </TBODY></TABLE><TABLE cellSpacing=0 cellPadding=0 width=760 bgColor=#ffffff border=0> <TBODY> <TR> <TD><HR width=760 noShade SIZE=1> </TD> </TR> <TR> <TD align=middle><A class=black href="http://www.chinaren.com/" target=_blank>ChinaRen</A> - <A class=black href="http://big5.www.sohu.com/" target=_blank>繁体版</A> - <A class=black href="http://hr.sohu.com/hrm.html" target=_blank>搜狐招聘</A> - <A class=black href="http://add.sohu.com/" target=_blank>网站登录</A> - <A class=black href="http://help.sohu.com/" target=_blank>帮助中心</A> - <A class=black href="http://book.news.sohu.com/onClick=this.style.behavior='url(#default#homepage)';this.setHomePage('http://www.sohu.com');return" target=_blank false;>设置首页</A> - <A class=black href="http://adinfo.sohu.com/" target=_blank>广告服务</A> - <A class=black href="http://www.sohu.com/about/lianxi.htm" target=_blank>联系方式</A> - <A class=black href="http://www.sohu.com/about/privacy.html" target=_blank>保护隐私权</A> - <A class=black href="http://www.sohu.com/about/" target=_blank>About SOHU</A> - <A class=black href="http://www.sohu.com/about/" target=_blank>公司介绍</A><BR> <SPAN class=eng>Copyright © 2004 Sohu.com Inc. All rights reserved. 搜狐公司 版权所有</SPAN> </TD> </TR> </TBODY></TABLE></center></body></html><script language="JavaScript" src="http://nielsen.js.sohu.com/nnselect.js"></script><noscript><img src='http://ping.nnselect.com/ping.gif?c=119' height='1' width='1'></noscript>⌨️ 快捷键说明
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