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online courses</a></font><br x="7"><img src="imagemaster/masthead.jpg" alt="Building a Java chat server"></td><td width="*" valign="bottom" align="right"><a border="0" href="j-chat.zip"><img alt="Download tutorial zip file" border="0" src="../i/icon-zip.gif"></a><a border="0" href="j-chat-ltr.pdf"><img alt="View letter-sized PDF file" border="0" src="../i/icon-pdf-ltr.gif"></a><a border="0" href="j-chat-a4.pdf"><img alt="View A4-sized PDF file" border="0" src="../i/icon-pdf-a4.gif"></a><a href="javascript:void newWindow()" border="0"><img alt="E-mail this tutorial to a friend" border="0" src="../i/icon-email.gif"></a></td></tr><tr><td height="2" colspan="2"><img height="2" width="1" src="http://www.ibm.com/i/c.gif"></td></tr></table><TABLE border="0" cellpadding="0" cellspacing="0" width="100%"><TR><TD width="150" height="1" bgcolor="#000000" colspan="6"><IMG alt="" height="1" width="150" src="http://www.ibm.com/i/c.gif"></TD></TR><TR><TD background="../i/sw-gold.gif"><a border="0" href="index.html" onMouseOver="iOver('topmain'); iOver('bottommain'); self.status=mainblurb; return true;" onMouseOut="iOut('topmain'); iOut('bottommain'); self.status=''; return true;"><img alt="Main menu" border="0" src="../i/main.gif" name="topmain"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topsection'); iOver('bottomsection'); self.status=sectionblurb; return true;" onMouseOut="iOut('topsection'); iOut('bottomsection'); self.status=''; return true;" href="index7.html"><img alt="Section menu" border="0" src="../i/section.gif" name="topsection"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topfeedback'); iOver('bottomfeedback'); self.status=feedbackblurb; return true;" onMouseOut="iOut('topfeedback'); iOut('bottomfeedback'); self.status=''; return true;" href="j-chat-11-3.html"><img alt="Give feedback on this tutorial" border="0" src="../i/feedback.gif" name="topfeedback"></a></TD><TD width="100%" background="../i/sw-gold.gif"><img src="http://www.ibm.com/i/c.gif"></TD><TD background="../i/sw-gold.gif"><img border="0" src="../i/xprevious.gif"></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topnext'); iOver('bottomnext'); self.status=nextblurb; return true;" onMouseOut="iOut('topnext'); iOut('bottomnext'); self.status=''; return true;" href="j-chat-7-2.html"><img alt="Next" border="0" src="../i/next.gif" name="topnext"></a></TD></TR></TABLE><table bgcolor="ffffff" cellspacing="0" cellpadding="2" border="0" height="400" width="100%"><tr valign="bottom"><a name="navskip"></a><td height="25" colspan="4"><img border="0" height="25" width="562" src="imagemaster/titlebar7.jpg" alt="7. Removing dead connections"></td></tr><tr><td bgcolor="ffffff" width="15">&nbsp;</td><td bgcolor="ffffff" width="12">&nbsp;</td><td valign="top" align="left" bgcolor="ffffff" width="*"><p><br x="7"><table cellspacing="0" cellpadding="0" border="0"><tr><td width="90%"><font size="4" face="Verdana, Arial, Helvetica"><b>Removing dead connections</b></font></td><td width="200" align="right"><font size="1" face="Verdana, Arial, Helvetica"><nobr>    page 1 of 2</nobr></font></td></tr></table><br x="7"><br x="7"></p><font size="2" face="Verdana, Arial, Helvetica"><p>The second place that our Per-Thread class refers to the main Server
object is near the bottom, where we are removing a socket after the
connection has closed. More precisely, our Per-Thread class, once it
realizes that the connection has closed, must ask the Server to remove
that connection so that we can be done with it. Here is the code:</p><pre><code style="font-family: Courier New, Courier, monospace; font-size: 12">
      // The connection is closed for one reason or another,
      // so have the server dealing with it
      server.removeConnection( socket );
</code></pre><p>It is important to inform the main Server object each time a
connection has closed, so that the server can remove the connection from any internal
lists, and also so that the server doesn't waste time sending messages to
clients that are no longer connected.</p><br x="7"></font></td></tr></table><TABLE border="0" cellpadding="0" cellspacing="0" width="100%"><TR><TD background="../i/sw-gold.gif"><a border="0" href="index.html" onMouseOver="iOver('topmain'); iOver('bottommain'); self.status=mainblurb; return true;" onMouseOut="iOut('topmain'); iOut('bottommain'); self.status=''; return true;"><img alt="Main menu" border="0" src="../i/main.gif" name="bottommain"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topsection'); iOver('bottomsection'); self.status=sectionblurb; return true;" onMouseOut="iOut('topsection'); iOut('bottomsection'); self.status=''; return true;" href="index7.html"><img alt="Section menu" border="0" src="../i/section.gif" name="bottomsection"></a></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topfeedback'); iOver('bottomfeedback'); self.status=feedbackblurb; return true;" onMouseOut="iOut('topfeedback'); iOut('bottomfeedback'); self.status=''; return true;" href="j-chat-11-3.html"><img alt="Give feedback on this tutorial" border="0" src="../i/feedback.gif" name="bottomfeedback"></a></TD><TD width="100%" background="../i/sw-gold.gif"><img src="http://www.ibm.com/i/c.gif"></TD><TD background="../i/sw-gold.gif"><img border="0" src="../i/xprevious.gif"></TD><TD background="../i/sw-gold.gif"><a border="0" onMouseOver="iOver('topnext'); iOver('bottomnext'); self.status=nextblurb; return true;" onMouseOut="iOut('topnext'); iOut('bottomnext'); self.status=''; return true;" href="j-chat-7-2.html"><img alt="Next" border="0" src="../i/next.gif" name="bottomnext"></a></TD></TR><TR><TD width="150" height="1" bgcolor="#000000" colspan="6"><IMG alt="" height="1" width="150" src="http://www.ibm.com/i/c.gif"></TD></TR></TABLE><TABLE cellpadding="0" cellspacing="0" border="0"><TR><TD width="182"><TABLE cellpadding="0" cellspacing="0" border="0" width="182"><TR bgcolor="#000000"><TD align="center" width="60" class="mast"><a style="text-decoration: none; color: #ffffff;" class="nav" href="http://www.ibm.com/privacy/"><font face="Arial, Verdana" size="2">Privacy</font></a></TD><TD width="1" bgcolor="#959595"><img alt="" border="0" height="20" width="1" src="http://www.ibm.com/i/c.gif"></TD><TD align="center" width="60" class="mast"><a style="text-decoration: none; color: #ffffff;" class="nav" href="http://www.ibm.com/legal/"><font face="Arial, Verdana" size="2">Legal</font></a></TD><TD width="1" bgcolor="#959595"><img alt="" border="0" height="20" width="1" src="http://www.ibm.com/i/c.gif"></TD><TD align="center" width="60" class="mast"><a style="text-decoration: none; color: #ffffff;" class="nav" href="http://www.ibm.com/contact/"><font face="Arial, Verdana" size="2">Contact</font></a></TD><TD width="1" bgcolor="#959595"><img alt="" border="0" height="21" width="1" src="http://www.ibm.com/i/c.gif"></TD></TR><TR bgcolor="#ffffff"><TD><img alt="" border="0" height="1" width="1" src="http://www.ibm.com/i/c.gif"></TD></TR></TABLE></TD><TD width="100%"><TABLE cellpadding="0" cellspacing="0" border="0" width="100%"><TR height="21" bgcolor="#000000"><TD><img alt="" border="0" height="21" width="1" src="http://www.ibm.com/i/c.gif"></TD></TR><TR bgcolor="#ffffff"><TD><img alt="" border="0" height="1" width="1" src="http://www.ibm.com/i/c.gif"></TD></TR></TABLE></TD></TR></TABLE></body></html>