帮我看看我的问题在哪里？jsp

2009-12-31 10:27:54 141 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

<%
Connection con = null;
Statement sm = null;
ResultSet rs = null;
InitialContext ctx=new InitialContext();
DataSource ds=(DataSource)ctx.lookup("java:comp/env/jdbc/mysql");
con=ds.getConnection();
sm=con.createStatement();
rs = sm.executeQuery("select * from wen ");

while(rs.next()) {
String s_time = rs.getString("time");
int s_number =Integer.parseInt(rs.getString("number"));
{
if(s_number==1){
String s_one = rs.getString("wendu");
}
else if(s_number==2){
String s_two = rs.getString("wendu");
}
else if(s_number==3){
String s_three = rs.getString("wendu");
}
else if(s_number==4){
String s_four = rs.getString("wendu");
}
else if(s_number==5){
String s_five = rs.getString("wendu");
}
else if(s_number==6){
String s_six = rs.getString("wendu");
}
else if(s_number==7){
String s_seven = rs.getString("wendu");
}
else if(s_number==8){
String s_eight = rs.getString("wendu");
}
else if(s_number==9){
String s_nine = rs.getString("wendu");
}
else {
String s_ten = rs.getString("wendu");
}
}
%>
<tr>
<td width="110" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_time%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_one%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_two%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_three%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_four%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_five%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_six%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_seven%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_eight%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_nine%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_ten%></td>
</tr>
<%
}
%>

...全文

publicom20

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切换为时间正序

publicom20 2009-12-31

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[Quote=引用 12 楼 yao0220 的回复:]
Java code<tr><td width="110" height="30" align="center" valign="middle"
bordercolor="#000000"class="STYLE22 STYLE25"><%=s_time%></td><td width="82" align="center" valign="middle" bordercolo?-
[/Quote]谢谢大哥

yao0220 2009-12-31

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<tr> 

     <td width="110" height="30" align="center" valign="middle" 

          bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_time%> 

     </td> 

     <td width="82" align="center" valign="middle" bordercolor="#000000"

          class="STYLE22 STYLE25"> <%=s_number==1?str:"" %> 

     </td> 

     <td width="82" align="center" valign="middle" bordercolor="#000000"

          class="STYLE22 STYLE25"> <%=s_number==2?str:""%> 

     </td>      

     <td width="82" align="center" valign="middle" bordercolor="#000000"

         class="STYLE22 STYLE25"> <%=s_number==3?str:""%> 

     </td> 

     <td width="82" align="center" valign="middle" bordercolor="#000000"

        class="STYLE22 STYLE25"> <%=s_number==4?str:""%> 

     </td> 

     <td width="82" align="center" valign="middle" bordercolor="#000000"

        class="STYLE22 STYLE25"> <%=s_number==5?str:""%> 

     </td>        

     <td width="82" align="center" valign="middle" bordercolor="#000000"

        class="STYLE22 STYLE25"> <%=s_number==6?str:""%> 

     </td> 

     <td width="82" align="center" valign="middle" bordercolor="#000000"

         class="STYLE22 STYLE25"> <%=s_number==7?str:""%> 

     </td> 

     <td width="82" align="center" valign="middle" bordercolor="#000000"

         class="STYLE22 STYLE25"> <%=s_number==8?str:""%> 

     </td> 

     <td width="82" align="center" valign="middle" bordercolor="#000000"

         class="STYLE22 STYLE25"> <%=s_number==9?str:""%> 

     </td> 

     <td width="82" align="center" valign="middle" bordercolor="#000000"

         class="STYLE22 STYLE25"> <%=s_number==10?str:""%> 

     </td> 

</tr>

publicom20 2009-12-31

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[Quote=引用 10 楼 yao0220 的回复:]
1、连接数据库的操作最好写在类里，相关数据库的操作方法也放在类里，这样页面传入sql语句获得结果集进行操作就可以了
2、尽量少创建变量，而且避免在循环里创建
3、我个人建议获得rs后，最好判断一下是否为空，再进行下一步操作
4、td里的高度设置只在第一个设置就可以了，其他的可以去掉，页面代码越少，访问就越快，尽量减少垃圾代码
Java code<%
InitialContext ctx=new InitialContext();
DataSource ds= (DataSource)ctx.lookup("java:comp/env/jdbc/mysql");
Connection conn= ds.getConnection();if(conn==null){
out.print("未获得数据连接");return;
}
PreparedStatement ps=null;
ResultSet rs=null;try{
ps= conn.createStatement();
rs= ps.executeQuery("select * from wen");if(rs!=null){
String s_time="",str="";int s_number=0;while(rs.next()) {
s_time= rs.getString("time");
s_number= Integer.parseInt(rs.getString("number"));
str= rs.getString("wendu");%><tr><td width="110" height="30" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_time%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==1?str:""%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==2?str:""%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==3?str:""%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==4?str:""%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==5?str:""%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==6?str:""%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==7?str:""%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==8?str:""%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==9?str:""%></td><td width="82" align="center" valign="middle" bordercolor="#000000"class="STYLE22 STYLE25"><%=s_number==10?str:""%></td></tr><%
}
}
}catch(Exception e){
e.printStackTrace();
}finally{if (rs!=null) {try {
rs.close();
}catch (SQLException e) {
e.printStackTrace();
}
rs=null;
}if (ps!=null) {try {
ps.close();
}catch (SQLException e) {
e.printStackTrace();
}
ps=null;
}if(con!=null){
conn.close();
conn=null;
}
}%>
[/Quote]
大哥，小弟要拜你为师

yao0220 2009-12-31

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1、连接数据库的操作最好写在类里，相关数据库的操作方法也放在类里，这样页面传入sql语句获得结果集进行操作就可以了
2、尽量少创建变量，而且避免在循环里创建
3、我个人建议获得rs后，最好判断一下是否为空，再进行下一步操作
4、td里的高度设置只在第一个设置就可以了，其他的可以去掉，页面代码越少，访问就越快，尽量减少垃圾代码



<%      

    InitialContext ctx = new InitialContext(); 

    DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/mysql"); 

    Connection conn = ds.getConnection();

    if(conn==null){

    	out.print("未获得数据连接");

    	return;

    }

    PreparedStatement ps = null;

    ResultSet rs = null;

    try{

    	ps = conn.createStatement(); 

        rs = ps.executeQuery("select * from wen"); 

        if(rs!=null){

        	String s_time = "",str = "";

        	int s_number = 0;

        	while(rs.next()) { 

        		s_time = rs.getString("time"); 

        		s_number = Integer.parseInt(rs.getString("number")); 

        		str = rs.getString("wendu");

%> 

        		  <tr> 

        		        <td width="110" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_time%> </td> 

        				<td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==1?str:"" %> </td> 

        		        <td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==2?str:""%> </td>      

        		        <td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==3?str:""%> </td> 

        		        <td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==4?str:""%> </td> 

        		        <td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==5?str:""%> </td>        

        		        <td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==6?str:""%> </td> 

        		        <td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==7?str:""%> </td> 

        		        <td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==8?str:""%> </td> 

        		        <td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==9?str:""%> </td> 

        		        <td width="82" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"> <%=s_number==10?str:""%> </td> 

        		        </tr> 

<% 

  		     } 

        }       

    }catch(Exception e){

    	e.printStackTrace(); 	

    }finally{

    	if (rs != null) {

			try {

				rs.close();

			} catch (SQLException e) {

				e.printStackTrace();

			}

			rs = null;

		}

    	if (ps != null) {

			try {

				ps.close();

			} catch (SQLException e) {

				e.printStackTrace();

			}

			ps = null;

		}

    	if(con!=null){

    		conn.close();

    		conn = null;

    	}

    }

%>

kx00450 2009-12-31

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把定义的10个变量放到while外面

dahaidao 2009-12-31

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你一点一点调一下。不太容易一下子看出来。

wflyxiaonian 2009-12-31

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出错不是这吧 s_ten没定义是前面取值的问题

publicom20 2009-12-31

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<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_one%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_two%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_three%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_four%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_five%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_six%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_seven%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_eight%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_nine%></td>
<td width="82" height="30" align="center" valign="middle" bordercolor="#000000" class="STYLE22 STYLE25"><%=s_ten%></td>

出错在这几行

publicom20 2009-12-31

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[Quote=引用 3 楼 xiesisi3 的回复:]
这么多重复代码，自己看着不烦吗。
[/Quote]我想给大家说详细点

publicom20 2009-12-31

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[Quote=引用 1 楼 kaoh1631 的回复:]
出错信息贴出来
[/Quote]
An error occurred at line: 265 in the jsp file: /ceshi.jsp
Generated servlet error:
s_ten cannot be resolved

at org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:84)
at org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:328)
at org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:414)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:297)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:276)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:264)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:563)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:305)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Unknown Source)

xiesisi3 2009-12-31

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这么多重复代码，自己看着不烦吗。

VilenZYP 2009-12-31

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这种代码，真是个杯具。

Thinking_In_IT 2009-12-31

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出错信息贴出来