??xml version="1.0" encoding="utf-8" standalone="yes"?>视频一区二区中文字幕,99国产精品国产精品毛片,97精品超碰一区二区三区http://www.aygfsteel.com/zhangrenquan/category/6021.htmlzh-cnMon, 23 Apr 2007 02:16:55 GMTMon, 23 Apr 2007 02:16:55 GMT60JSP下蝲文ghttp://www.aygfsteel.com/zhangrenquan/archive/2006/04/14/41116.htmlkelvenkelvenFri, 14 Apr 2006 08:04:00 GMThttp://www.aygfsteel.com/zhangrenquan/archive/2006/04/14/41116.htmlhttp://www.aygfsteel.com/zhangrenquan/comments/41116.htmlhttp://www.aygfsteel.com/zhangrenquan/archive/2006/04/14/41116.html#Feedback2http://www.aygfsteel.com/zhangrenquan/comments/commentRss/41116.htmlhttp://www.aygfsteel.com/zhangrenquan/services/trackbacks/41116.html<%@ page import="java.io.*"%>
<%
String root=application.getRealPath("/");
String fileName=request.getParameter("fileName");
String filePath=request.getParameter("filePath");

response.setContentType("application/octet-stream");
response.setHeader("Content-Disposition",
"attachment; filename=\"" +fileName+ "\"");

try{
java.io.OutputStream os = response.getOutputStream(); //不加此行只能下载文本文?下蝲jpg{就会出现打不开的现?
java.io.FileInputStream fis = new java.io.FileInputStream(root+filePath);
byte[] b = new byte[1024];
int i = 0;
while ( (i = fis.read(b)) > 0 )
{
os.write(b, 0, i);
}

fis.close();
os.flush();
os.close();
}
catch ( Exception e )
{
System.out.println ( "IOException." + e );
}
%>

java.io.FileInputStream fis = new java.io.FileInputStream(文g的真实\?;
也可?br>
<%
if (request.getParameter("fileUrl") != null)
{
String strFileUrl = request.getParameter("fileUrl");

//获取文g名(DealFile是自己写的一个处理文件的一个类Q?br>DealFile dealFile = new DealFile(strFileUrl);
String filename = dealFile.getFileName();

response.setHeader("content-type","application/octet-stream");
response.setHeader("Content-Disposition","attachment;filename=\""+ filename+"\"");

BufferedInputStream bis = null;
BufferedOutputStream bos = null;
try
{
//从文件所在目录以的方式d文g
bis = new BufferedInputStream(new FileInputStream(getServletContext().getRealPath(strFileUrl)));

bos = new BufferedOutputStream(response.getOutputStream());

byte[] buff = new byte[2048];
int bytesRead;

while(-1 != (bytesRead = bis.read(buff, 0, buff.length)))
{
bos.write(buff,0,bytesRead);
}
bos.flush();
}
catch(final IOException e)
{
System.out.println ( "IOException." + e );
}
finally
{
if (bis != null)
bis.close();
if (bos != null)
bos.close();
}
return;
}
%>



kelven 2006-04-14 16:04 发表评论
]]>
JAVA开发者应该去?0个英文网?/title><link>http://www.aygfsteel.com/zhangrenquan/archive/2006/04/05/39375.html</link><dc:creator>kelven</dc:creator><author>kelven</author><pubDate>Wed, 05 Apr 2006 06:03:00 GMT</pubDate><guid>http://www.aygfsteel.com/zhangrenquan/archive/2006/04/05/39375.html</guid><wfw:comment>http://www.aygfsteel.com/zhangrenquan/comments/39375.html</wfw:comment><comments>http://www.aygfsteel.com/zhangrenquan/archive/2006/04/05/39375.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.aygfsteel.com/zhangrenquan/comments/commentRss/39375.html</wfw:commentRss><trackback:ping>http://www.aygfsteel.com/zhangrenquan/services/trackbacks/39375.html</trackback:ping><description><![CDATA[ <p>[http://www.javaalmanac.com] - Java开发者年鉴一书的在线版本. 要想快速查到某UJava技巧的用法及示例代? q是一个不错的d. <br />[http://www.onjava.com] - O'Reilly的Java|站. 每周都有新文? <br />[http://java.sun.com] - 官方的Java开发者网?- 每周都有新文章发? <br />[http://www.developer.com/java] - 由Gamelan.com l护的Java技术文章网? <br />[http://www.java.net] - Sun公司l护的一个JavaC֌|站. <br />[http://www.builder.com] - Cnet的Builder.com|站 - 所有的技术文? 以JavaZ. <br />[http://www.ibm.com/developerworks/java] - IBM的Developerworks技术网? q是其中的Java技术主? <br />[http://www.javaworld.com] - 最早的一个Java站点. 每周更新Java技术文? <br />[http://www.devx.com/java] - DevXl护的一个Java技术文章网? <br />[http://www.fawcette.com/javapro] - JavaPro在线杂志|站. <br />[http://www.sys-con.com/java] - Java Developers Journal的在U杂志网? <br />[http://www.javadesktop.org] - 位于Java.net的一个Java桌面技术社区网? <br />[http://www.theserverside.com] - q是一个讨论所有Java服务器端技术的|站. <br />[http://www.jars.com] - 提供Java评论服务. 包括各种framework和应用程? <br />[http://www.jguru.com] - 一个非常棒的采用Q&A形式的Java技术资源社? <br />[http://www.javaranch.com] - 一个论坛,得到Java问题{案的地方,初学者的好去处?<br />[http://www.ibiblio.org/javafaq/javafaq.html] - comp.lang.java的FAQ站点 - 攉了来自comp.lang.java新闻l的问题和答案的分类目录. <br />http://java.sun.com/docs/books/tutorial/] - 来自SUN公司的官方Java指南 - 对于了解几乎所有的java技术特性非常有帮助. <br />http://www.javablogs.com] - 互联|上最z跃的一个Java Blog|站. <br />http://java.about.com/] - 来自About.com的Java新闻和技术文章网?</p> <img src ="http://www.aygfsteel.com/zhangrenquan/aggbug/39375.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.aygfsteel.com/zhangrenquan/" target="_blank">kelven</a> 2006-04-05 14:03 <a href="http://www.aygfsteel.com/zhangrenquan/archive/2006/04/05/39375.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>q接SQLserver数据库注意事?/title><link>http://www.aygfsteel.com/zhangrenquan/archive/2006/02/17/31180.html</link><dc:creator>kelven</dc:creator><author>kelven</author><pubDate>Fri, 17 Feb 2006 03:59:00 GMT</pubDate><guid>http://www.aygfsteel.com/zhangrenquan/archive/2006/02/17/31180.html</guid><wfw:comment>http://www.aygfsteel.com/zhangrenquan/comments/31180.html</wfw:comment><comments>http://www.aygfsteel.com/zhangrenquan/archive/2006/02/17/31180.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.aygfsteel.com/zhangrenquan/comments/commentRss/31180.html</wfw:commentRss><trackback:ping>http://www.aygfsteel.com/zhangrenquan/services/trackbacks/31180.html</trackback:ping><description><![CDATA[?A target=_blank><FONT color=#3366cc>Java</FONT></A>文g中,q接SQLserver数据库时Q需要一个连接数据库?A target=_blank><FONT color=#3366cc>驱动</FONT></A>文g?<BR><BR>在你安装<A target=_blank><FONT color=#3366cc>JDK</FONT></A>的\径下的lib文g多w拯一个文件jtds-0.6.jarQƈ且在环境变量里设|classpathQ例如:你的jdk装在c:\jdkQ那么环境变量classpath的\径应设ؓc:\jdk\lib\jtds-0.6.jar。(环境变量知道q么讑֐Q在我的电脑的属性,高里。多个\径之间用分号隔开。) <BR><BR>q里提供SQLserverq接驱动文gjtds-0.6.jarQ?A target=_blank><FONT color=#3366cc>下蝲</FONT></A>解压后拷贝到jdk路径下的lib文g多w?<BR><BR>具体在文件中的应用: <BR><BR>import java.sql.*; <BR>String url="<A target=_blank><FONT color=#3366cc>JDBC</FONT></A>:jtds:sqlserver://localhost:1433/‘数据库名?Q?<BR>String driver="net.sourceforge.jtds.jdbc.Driver"; <BR>Class.forName(driver); <BR>Connection conn=DriverManager.getConnection(url,"用户?,"密码"); <BR>可以连接到你的数据库了?<BR><BR>1433是SQLserver默认的端口号,如果要连接到其他机器上,要将localhost改ؓ其他机器的IP地址Q如192.168.0.101?<BR><BR><BR>其中数据库名是你所新徏的数据库的名Uͼ用户名和密码是你登陆SQLserver是的用户名和密码?<BR><BR>有的人安装SQLserver时用的是<A target=_blank><FONT color=#3366cc>Windows</FONT></A>w䆾验证Q那么用户名和密码都为空。如果不能登陆,或者要用SQLw䆾验证的话Q需要修?A target=_blank><FONT color=#3366cc>注册?/FONT></A>。在q行里打开regeditQ然后查找loginmodeQ具体位|:hkey_local_machine\software\microsoft\<A target=_blank><FONT color=#3366cc>MSSQL</FONT></A>server\ <BR>mssqlserver\Q,仅用Windowsw䆾验证的gؓ1Q؜合n份验证的gؓ2。只要将1改ؓ2Q就可以用SQLw䆾验证了,用户名ؓ‘sa'Q密码ؓI?img src ="http://www.aygfsteel.com/zhangrenquan/aggbug/31180.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.aygfsteel.com/zhangrenquan/" target="_blank">kelven</a> 2006-02-17 11:59 <a href="http://www.aygfsteel.com/zhangrenquan/archive/2006/02/17/31180.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>java提供文g下蝲的方?/title><link>http://www.aygfsteel.com/zhangrenquan/archive/2006/02/16/30959.html</link><dc:creator>kelven</dc:creator><author>kelven</author><pubDate>Thu, 16 Feb 2006 04:21:00 GMT</pubDate><guid>http://www.aygfsteel.com/zhangrenquan/archive/2006/02/16/30959.html</guid><wfw:comment>http://www.aygfsteel.com/zhangrenquan/comments/30959.html</wfw:comment><comments>http://www.aygfsteel.com/zhangrenquan/archive/2006/02/16/30959.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.aygfsteel.com/zhangrenquan/comments/commentRss/30959.html</wfw:commentRss><trackback:ping>http://www.aygfsteel.com/zhangrenquan/services/trackbacks/30959.html</trackback:ping><description><![CDATA[<BR><BR> <DIV style="BORDER-RIGHT: #cccccc 1px solid; PADDING-RIGHT: 5px; BORDER-TOP: #cccccc 1px solid; PADDING-LEFT: 4px; FONT-SIZE: 13px; PADDING-BOTTOM: 4px; BORDER-LEFT: #cccccc 1px solid; WIDTH: 98%; WORD-BREAK: break-all; PADDING-TOP: 4px; BORDER-BOTTOM: #cccccc 1px solid; BACKGROUND-COLOR: #eeeeee"><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top><SPAN style="COLOR: #000000">    String root </SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000"> getServletContext().getRealPath(</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">/</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">);<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top>    String path </SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000"> request.getParameter(</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">path</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">);<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top>    String name </SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000"> request.getParameter(</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">name</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">);<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top>    response.setContentType(</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">unknown</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">);<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top>    response.addHeader(</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">Content-Disposition</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">, </SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">filename=\</SPAN><SPAN style="COLOR: #000000">""</SPAN><SPAN style="COLOR: #000000"> + name + </SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">\</SPAN><SPAN style="COLOR: #000000">""</SPAN><SPAN style="COLOR: #000000">);<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top>    </SPAN><SPAN style="COLOR: #0000ff">try</SPAN><SPAN style="COLOR: #000000"><BR><IMG id=Codehighlighter1_286_661_Open_Image onclick="this.style.display='none'; Codehighlighter1_286_661_Open_Text.style.display='none'; Codehighlighter1_286_661_Closed_Image.style.display='inline'; Codehighlighter1_286_661_Closed_Text.style.display='inline';" src="http://www.aygfsteel.com/images/OutliningIndicators/ExpandedBlockStart.gif" align=top><IMG id=Codehighlighter1_286_661_Closed_Image style="DISPLAY: none" onclick="this.style.display='none'; Codehighlighter1_286_661_Closed_Text.style.display='none'; Codehighlighter1_286_661_Open_Image.style.display='inline'; Codehighlighter1_286_661_Open_Text.style.display='inline';" src="http://www.aygfsteel.com/images/OutliningIndicators/ContractedBlock.gif" align=top>    </SPAN><SPAN id=Codehighlighter1_286_661_Closed_Text style="BORDER-RIGHT: #808080 1px solid; BORDER-TOP: #808080 1px solid; DISPLAY: none; BORDER-LEFT: #808080 1px solid; BORDER-BOTTOM: #808080 1px solid; BACKGROUND-COLOR: #ffffff"><IMG src="http://www.aygfsteel.com/images/dot.gif"></SPAN><SPAN id=Codehighlighter1_286_661_Open_Text><SPAN style="COLOR: #000000">{<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top>        java.io.OutputStream    os  </SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000"> response.getOutputStream();<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top>        java.io.FileInputStream fis </SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000"> </SPAN><SPAN style="COLOR: #0000ff">new</SPAN><SPAN style="COLOR: #000000"> java.io.FileInputStream(root </SPAN><SPAN style="COLOR: #000000">+</SPAN><SPAN style="COLOR: #000000"> path </SPAN><SPAN style="COLOR: #000000">+</SPAN><SPAN style="COLOR: #000000"> name);<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top>        </SPAN><SPAN style="COLOR: #0000ff">byte</SPAN><SPAN style="COLOR: #000000">[] b </SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000"> </SPAN><SPAN style="COLOR: #0000ff">new</SPAN><SPAN style="COLOR: #000000"> </SPAN><SPAN style="COLOR: #0000ff">byte</SPAN><SPAN style="COLOR: #000000">[</SPAN><SPAN style="COLOR: #000000">1024</SPAN><SPAN style="COLOR: #000000">];<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top>        </SPAN><SPAN style="COLOR: #0000ff">int</SPAN><SPAN style="COLOR: #000000">    i </SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000"> </SPAN><SPAN style="COLOR: #000000">0</SPAN><SPAN style="COLOR: #000000">;<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top>        </SPAN><SPAN style="COLOR: #0000ff">while</SPAN><SPAN style="COLOR: #000000"> ( (i </SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000"> fis.read(b)) </SPAN><SPAN style="COLOR: #000000">></SPAN><SPAN style="COLOR: #000000"> </SPAN><SPAN style="COLOR: #000000">0</SPAN><SPAN style="COLOR: #000000"> ) <BR><IMG id=Codehighlighter1_551_592_Open_Image onclick="this.style.display='none'; Codehighlighter1_551_592_Open_Text.style.display='none'; Codehighlighter1_551_592_Closed_Image.style.display='inline'; Codehighlighter1_551_592_Closed_Text.style.display='inline';" src="http://www.aygfsteel.com/images/OutliningIndicators/ExpandedSubBlockStart.gif" align=top><IMG id=Codehighlighter1_551_592_Closed_Image style="DISPLAY: none" onclick="this.style.display='none'; Codehighlighter1_551_592_Closed_Text.style.display='none'; Codehighlighter1_551_592_Open_Image.style.display='inline'; Codehighlighter1_551_592_Open_Text.style.display='inline';" src="http://www.aygfsteel.com/images/OutliningIndicators/ContractedSubBlock.gif" align=top>        </SPAN><SPAN id=Codehighlighter1_551_592_Closed_Text style="BORDER-RIGHT: #808080 1px solid; BORDER-TOP: #808080 1px solid; DISPLAY: none; BORDER-LEFT: #808080 1px solid; BORDER-BOTTOM: #808080 1px solid; BACKGROUND-COLOR: #ffffff"><IMG src="http://www.aygfsteel.com/images/dot.gif"></SPAN><SPAN id=Codehighlighter1_551_592_Open_Text><SPAN style="COLOR: #000000">{<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top>            os.write(b, </SPAN><SPAN style="COLOR: #000000">0</SPAN><SPAN style="COLOR: #000000">, i);<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/ExpandedSubBlockEnd.gif" align=top>        }</SPAN></SPAN><SPAN style="COLOR: #000000"><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top>        fis.close();<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top>        os.flush();<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/InBlock.gif" align=top>        os.close();<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/ExpandedBlockEnd.gif" align=top>    }</SPAN></SPAN><SPAN style="COLOR: #000000"><BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/None.gif" align=top>    </SPAN><SPAN style="COLOR: #0000ff">catch</SPAN><SPAN style="COLOR: #000000"> ( Exception e )<BR><IMG id=Codehighlighter1_693_699_Open_Image onclick="this.style.display='none'; Codehighlighter1_693_699_Open_Text.style.display='none'; Codehighlighter1_693_699_Closed_Image.style.display='inline'; Codehighlighter1_693_699_Closed_Text.style.display='inline';" src="http://www.aygfsteel.com/images/OutliningIndicators/ExpandedBlockStart.gif" align=top><IMG id=Codehighlighter1_693_699_Closed_Image style="DISPLAY: none" onclick="this.style.display='none'; Codehighlighter1_693_699_Closed_Text.style.display='none'; Codehighlighter1_693_699_Open_Image.style.display='inline'; Codehighlighter1_693_699_Open_Text.style.display='inline';" src="http://www.aygfsteel.com/images/OutliningIndicators/ContractedBlock.gif" align=top>    </SPAN><SPAN id=Codehighlighter1_693_699_Closed_Text style="BORDER-RIGHT: #808080 1px solid; BORDER-TOP: #808080 1px solid; DISPLAY: none; BORDER-LEFT: #808080 1px solid; BORDER-BOTTOM: #808080 1px solid; BACKGROUND-COLOR: #ffffff"><IMG src="http://www.aygfsteel.com/images/dot.gif"></SPAN><SPAN id=Codehighlighter1_693_699_Open_Text><SPAN style="COLOR: #000000">{<BR><IMG src="http://www.aygfsteel.com/images/OutliningIndicators/ExpandedBlockEnd.gif" align=top>    }</SPAN></SPAN></DIV><img src ="http://www.aygfsteel.com/zhangrenquan/aggbug/30959.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.aygfsteel.com/zhangrenquan/" target="_blank">kelven</a> 2006-02-16 12:21 <a href="http://www.aygfsteel.com/zhangrenquan/archive/2006/02/16/30959.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>MySQL的嵌套查?/title><link>http://www.aygfsteel.com/zhangrenquan/archive/2005/10/31/17595.html</link><dc:creator>kelven</dc:creator><author>kelven</author><pubDate>Mon, 31 Oct 2005 13:34:00 GMT</pubDate><guid>http://www.aygfsteel.com/zhangrenquan/archive/2005/10/31/17595.html</guid><wfw:comment>http://www.aygfsteel.com/zhangrenquan/comments/17595.html</wfw:comment><comments>http://www.aygfsteel.com/zhangrenquan/archive/2005/10/31/17595.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.aygfsteel.com/zhangrenquan/comments/commentRss/17595.html</wfw:commentRss><trackback:ping>http://www.aygfsteel.com/zhangrenquan/services/trackbacks/17595.html</trackback:ping><description><![CDATA[1. SELECT语句的子查询:<BR>语法:     SELECT ... FROM (subquery) AS name ...<BR><BR>先创Z个表:<BR>CREATE TABLE t1 (s1 INT, s2 CHAR(5), s3 FLOAT);<BR>INSERT INTO t1 VALUES (1,'1',1.0);<BR>INSERT INTO t1 VALUES (2,'2',2.0);<BR><BR>我们可以进行以下的嵌套查询?<BR>SELECT sb1,sb2,sb3<BR>       FROM (SELECT s1 AS sb1, s2 AS sb2, s3*2 AS sb3 FROM t1) AS sb<BR>       WHERE sb1 > 1;<BR><BR>l果是: <FONT color=#000000>2<CODE><FONT face=新宋?, '2', 4.0</FONT></CODE>. <BR></FONT><BR>我们知道下面语句是不会得到正结果的Q因为对l过Group by排序的集合进行求均值是不能得到正确{案的:<BR>SELECT AVG(SUM(column1)) FROM t1 GROUP BY column1<BR><BR>所以我们可以通过下面的嵌套查询实现同L效果Q?BR>SELECT AVG(sum_column1)<BR>       FROM (SELECT SUM(column1) AS sum_column1<BR>             FROM t1 GROUP BY column1) AS t1;<BR><BR>2.行的子查询(Row SubqueryQ:<BR>看下面的例子Q?BR>SELECT * FROM t1 WHERE ROW(1,2) = (SELECT column1, column2 FROM t2);<BR>q个查询是返回column1{于column2的结果行。Row函数中的1?相当于构造参数。想必Blogjava上的同志对这些应该比较清楚,也不去详l介l了?BR><BR>3.使用Exist和Not Exist参数<BR>q里的Exist和Not Exist用途及用法和在其他没有什么大的区?我就单D几个范例好了:<BR><BR>范例一:      SELECT DISTINCT store_type FROM Stores<BR>                    WHERE EXISTS (SELECT * FROM Cities_Stores<BR>                                  WHERE Cities_Stores.store_type = Stores.store_type);<BR>范例?   SELECT DISTINCT store_type FROM Stores<BR>                       WHERE NOT EXISTS (SELECT * FROM Cities_Stores<BR>                                   WHERE Cities_Stores.store_type = Stores.store_type);<BR>范例?  q个例子中嵌套用了Not Exist语法Q稍微注意一下:<BR>               SELECT DISTINCT store_type FROM Stores S1<BR>                    WHERE NOT EXISTS (<BR>                               SELECT * FROM Cities WHERE NOT EXISTS (<BR>                                       SELECT * FROM Cities_Stores<BR>                                                 WHERE Cities_Stores.city = Cities.city<BR>                                                         AND Cities_Stores.store_type = Stores.store_type));<BR><BR>4.条g兌关系查询Q?BR>解释hȝQ直接看例子吧:<BR>SELECT column1 FROM t1 AS x<BR>     WHERE x.column1 = (SELECT column1 FROM t2 AS x<BR>          WHERE x.column1 = (SELECT column1 FROM t3<BR>               WHERE x.column2 = t3.column1));<BR>跟其他数据库做法是一L?BR><BR>5.其他使用Ҏ和注意:<BR>除了上面q些q有很多很多Q不q就不去l讲了,因ؓq些跟别的数据库差不多,只是Zl大家一个参考,提提够了?BR><BR>         SELECT (SELECT s1 FROM t2) FROM t1;<BR>         SELECT (SELECT s2 FROM t1);<BR><BR>支持子查询的语法有:SELECTQINSERTQUPDATEQDELETEQSET和DO?BR><BR>子查询可以用Q何普通查询中使用的关键词Q如DINSTINCTQGROUP BYQLIMITQORDER BYQUNIONQALLQUNION ALL{。可以?lt;,>, <=, >=, =, <>q算W进行比较,也可以用ANY QIN和SOMEq行集合的匹配?img src ="http://www.aygfsteel.com/zhangrenquan/aggbug/17595.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.aygfsteel.com/zhangrenquan/" target="_blank">kelven</a> 2005-10-31 21:34 <a href="http://www.aygfsteel.com/zhangrenquan/archive/2005/10/31/17595.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>java 文g操作大全http://www.aygfsteel.com/zhangrenquan/archive/2005/10/31/17594.htmlkelvenkelvenMon, 31 Oct 2005 13:30:00 GMThttp://www.aygfsteel.com/zhangrenquan/archive/2005/10/31/17594.htmlhttp://www.aygfsteel.com/zhangrenquan/comments/17594.htmlhttp://www.aygfsteel.com/zhangrenquan/archive/2005/10/31/17594.html#Feedback0http://www.aygfsteel.com/zhangrenquan/comments/commentRss/17594.htmlhttp://www.aygfsteel.com/zhangrenquan/services/trackbacks/17594.html文g的徏?查与删除

<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>文g的徏立、检查与删除</title>
</head>
<body>
<%
    String path=request.getRealPath("");
    //out.println(path);
    File f=new File(path,"File.txt");
    //out.println(f);
    //out.println(f.exists());
 
    //查File.txt是否存在
    if(f.exists()){
        f.delete();//删除File.txt文g
        out.println(path + "\\File.txt 存在Q已删除?);
    }else{
        f.createNewFile();//在当前目录下建立一个名为File.txt的文?
        out.println(path + "\\File.txt 不存在,已徏立?);//输出目前所在的目录路径
     }
%>


目录的徏?查与删除

<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>目录的徏?查与删除</title>
</head>
<body>
<%
    String path=request.getRealPath("");
    path=path + "\\Sub";//要建立的目录\?
    File d=new File(path);//建立代表Sub目录的File对象Qƈ得到它的一个引?
    if(d.exists()){//查Sub目录是否存在
        d.delete();
        ("Sub目录存在Q已删除");
    }else{
        d.mkdir();//建立Sub目录
        out.println("Sub目录不存在,已徏?);
    }
%>
</body>
</html>


如何在JSP中处理虚拟目?/STRONG>

<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>JSP中如何处理虚拟目?lt;/title>
</head>
<body>
取得虚拟目录对应的磁盘\?lt;br>
Web站点ȝ录的位置?lt;font color=#ff0000><%=request.getRealPath("/")%></font><br>
JSP|页所在的目录位置<font color=#ff0000><%=request.getRealPath("./")%></font><br>
JSP|页所在目录上一层目录的位置<font color=#ff0000><%=request.getRealPath("../")%></font><br>
</body>
</html>


文g属性的取得
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.util.Date,java.io.*"%>
<html>
<head>
<title>文g属性的取得</title>
</head>
<body>
<%
String path=request.getRealPath("/");
File f=new File(path,"ReadData.txt");
if(f.exists()){
%>
    <%=f.getName()%>的属性如下:<br><br>
    文g长度为:<%=f.length()%>
    <%=f.isFile()?"是文?:"不是文g"%><br>
    <%=f.isDirectory()?"是目?:"不是目录"%><br>
    <%=f.canRead()?"可读?:"不可d"%><br>
    <%=f.canWrite()?"可写?:"不可写入"%><br>
    <%=f.isHidden()?"是隐藏文?:"不是隐藏文g"%><br>
    文g的最后修Ҏ期ؓQ?lt;%=new Date(f.lastModified())%><br>
<%
}else{
    f.createNewFile();//在当前目录下建立一个名为ReaData.txt的文?
%>
    <%=f.getName()%>的属性如下:<br><br>
    文g长度为:<%=f.length()%>
    <%=f.isFile()?"是文?:"不是文g"%><br>
    <%=f.isDirectory()?"是目?:"不是目录"%><br>
    <%=f.canRead()?"可读?:"不可d"%><br>
    <%=f.canWrite()?"可写?:"不可写入"%><br>
    <%=f.isHidden()?"是隐藏文?:"不是隐藏文g"%><br>
    文g的最后修Ҏ期ؓQ?lt;%=new Date(f.lastModified())%><br>
<%
}
%>
</body>
</html>
 

取出目录中文件的Ҏ

<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>取出目录中文件的Ҏ--列出目录中的文g</title>
</head>
<body>
<%
    String path=request.getRealPath("/");
    File d=new File(path);//建立当前目录中文件的File对象
    File list[]=d.listFiles();//取得代表目录中所有文件的File对象数组
    out.println("<font color=#ff0000>" + path + "目录下的文gQ?lt;/font><br>");
    for(int i=0;i<list.length;i++){
        if(list<I>.isFile()){
            out.println(list<I>.getName() + "<br>");
        }
    }
    out.println("<br><font color=#ff0000>" + path + "目录下的目录Q?lt;/font><br>");
    for(int i=0;i<list.length;i++){
        if(list<I>.isDirectory()){
                out.println(list<I>.getName() + "<br>");
        }
    }
%>
</body>
</html>


判断是否为空白文?
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>判断是否为空白文?lt;/title>
</head>
<body>
<%
    String path=request.getRealPath("/");
    out.println(path);
    FileReader fr=new FileReader(path + "\\AtEnd.txt");//建立FileReader对象Qƈ实例化ؓfr
    //对FileReadercȝ成的对象使用read()ҎQ可以从字符中d下一个字W?
    if(fr.read()==-1)//判断是否已读到文件的l尾
    {
        out.print("AtEnd.txt文g中没有数?lt;br>");
    }else{
        out.println("AtEnd.txt文g中有数据");
    }
    fr.close();
%>
</body>
</html>
    <B>d所有的文g数据</B>
<ccid_nobr>
<table width="400" border="1" cellspacing="0" cellpadding="2"
bordercolorlight = "black" bordercolordark = "#FFFFFF" align="center">
<tr>
<td bgcolor="e6e6e6" class="code" style="font-size:9pt">
<pre><ccid_code> <%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*,java.lang.*"%>
<html>
<head>
<title>d所有的文g数据</title>
</head>
<body>
<%
    String path=request.getRealPath(".");
    FileReader fr=new FileReader(path + "\\ReadData.txt");
    //关键在于dq程中,要判断所d的字W是否已l到了文件的末尾Qƈ且这个字W是不是文g中的断行W,卛_断该字符值是否ؓ13

?
    int c=fr.read();//从文件中d一个字W?
    //判断是否已读到文件结?
    while(c!=-1){
        out.print((char)c);//输出d的数?
        c=fr.read();//从文件中l箋d数据
        if(c==13){//判断是否为断行字W?
            out.print("<br>");//输出分行标签
            fr.skip(1);//略过一个字W?
            /c=fr.read();//d一个字W?
        }
    }
    fr.close();
%>
</body>
</html>
  一行一行读取数?
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>文gd</title>
</head>
<body>
<%
    String path=request.getRealPath("");//取得当前目录的\?
    FileReader fr=new FileReader(path + "\\file\\inc\\t.txt");//建立FileReader对象Qƈ实例化ؓfr
    BufferedReader br=new BufferedReader(fr);//建立BufferedReader对象Qƈ实例化ؓbr
    String Line=br.readLine();//从文件读取一行字W串
    //判断d到的字符串是否不为空
    while(Line!=null){
        out.println(Line + "<br>");//输出从文件中d的数?
        Line=br.readLine();//从文件中l箋d一行数?
    }
    br.close();//关闭BufferedReader对象
    fr.close();//关闭文g
%>
</body>
</html>

略过文g中的字符不读?/STRONG>
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>略过字节不读?lt;/title>
</head>
<body>
<%
    String path=request.getRealPath(".");
    FileReader fr=new FileReader(path + "\\ReadData.txt");
    fr.skip(2);//跌2个字?
    int c=fr.read();//d一个字?
    while(c!=-1){
        out.print((char)c);
        c=fr.read();
    }
    fr.close();
%>
</body>
</html>
  数据写入文?
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>数据写入文?lt;/title>
</head>
<body>
<%
    String path=request.getRealPath(".");
    FileWriter fw=new FileWriter(path + "\\WriteData.txt");//建立FileWriter对象Qƈ实例化fw
    //字W串写入文g
    fw.write("大家好!");
    fw.write("本书是《JSP~程技巧?);
    fw.write("请多多指教!");
    fw.write("email:stride@sina.com");
    fw.close();

    FileReader fr=new FileReader(path + "\\WriteData.txt");
    BufferedReader br=new BufferedReader(fr);//建立BufferedReader对象Qƈ实例化ؓbr
    String Line=br.readLine();
    //d一行数?
    out.println(Line + "<br>");
    br.close();//关闭BufferedReader对象
    fr.close();
%>
</body>
</html>
  写入文件的数据分行
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>写入文件的数据分行</title>
</head>
<body>
<%
    String path=request.getRealPath(".");
    FileWriter fw=new FileWriter(path + "\\WriteData.txt");
    BufferedWriter bw=new BufferedWriter(fw);
    bw.write("大家好!");
    bw.write("本书是《JSP~程技巧》?);
    bw.newLine();//断行
    bw.write("请多多指教!");
    bw.newLine();//断行
    bw.write("email: stride@sina.com");
    bw.flush();//数据更新至文g
    fw.close();//关闭文g?
    out.println("写入文g内容为:<br>");
    FileReader fr=new FileReader(path + "\\WriteData.txt");
    BufferedReader br=new BufferedReader(fr);
    String Line=br.readLine();//d一行数?
    while(Line!=null){
        out.println(Line + "<br>");
        Line=br.readLine();
    }
    fr.close();
%>
</body>
</html>

如何数据追加写入到文g
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.io.*"%>
<html>
<head>
<title>写入文件的数据分行</title>
</head>
<body>
<%
 
%>
</body>
</html></I></I></I></>



kelven 2005-10-31 21:30 发表评论
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