为什么我的jsp对类似这样的代码都报错？

首先这是java代码和html代码的混合编程
另外这种方式正常的情况下是不会产生错误的
错误的原因看来是你的java代码出错！
好好检查你的java代码！

解决方案 »

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在去数据之前应该先调用sqlRst.next();
程序改为:
<%while(sqlRst.next()){%>
<tr>
　 <td><%=sqlRst.getString("name")%></td>
　 <td><%=sqlRst.getString("writer")%></td>
   <td><%=sqlRst.getString("ndate")%></td>
   <td><%=sqlRst.getString("press")%></td>
   <td><%=sqlRst.getString("price")%></td>
</tr>
<%}%>
谢谢大家，不过，我改了另外的方式写，其实就是想实现分页显示，看了以前的一些帖子里的程序照着写的，还是报错。
程序如下：请大家帮忙想想，我已经调了一天都没弄好。
<%@ page contentType="text/html; charset=GBK" %><%@ page language="java" import="java.sql.*"%>
<%@ page import="java.io.*"%>
<%@ page import="java.util.*"%>
<%!
public String getStr(String str)
{
  try
{
  String temp_p=str;
  byte[ ] temp_t=temp_p.getBytes("GBK");
  String temp=new String(temp_t);
  return temp;
}
catch(Exception e)
{
       e.printStackTrace();
}
return "null";
}
%>
<html><head>
<title>选择查询</title>
</head>
<body><table border="0" width="100%">
  <tr>
    <td width="100%">
      <table border="0" width="107%" height="86" bgcolor="#006699">
        <tr>
          <td width="21%" height="82" bgcolor="#006699" bordercolor="#006699" bordercolorlight="#006699" bordercolordark="#006699"><img border="0" src="index.1.gif" width="130" height="71"></td>
          <td width="43%" height="82" bgcolor="#006699">
            <table border="0" width="100%" height="61">
              <tr>
                <td width="100%" height="35" align="center"><font face="文鼎中隶简" size="4" color="#FFFFFF"><b>经济科学出版社</b></font></td>
              </tr>
              <tr>
                <td width="100%" height="18" align="center"><font face="文鼎中隶简" size="3" color="#FFFFFF"><b>Economic
                  Science</b></font></td>
              </tr>
            </table>
          </td>
          <td width="42%" height="82" bgcolor="#006699"><img border="0" src="index.2.jpg" width="386" height="80"></td>
        </tr>
      </table>
    </td>
  </tr>
</table>
<table border="0" width="100%" height="38">
  <tr>
    <td width="100%" height="34">
      <form method="POST" action="accord.jsp">
        
        <p style="margin-top: 0; margin-bottom: 0">书籍查询:<select size="1" name="accord">
<option value="0" selected>查询方式</option>
          <option value="1">主题词</option>
          <option value="2">出版社</option>
          <option value="3">专家名</option>
        </select><input type="text" name="name1" size="16"><input type="submit" value="go" name="B1"></p>
      </form>
    </td>
  </tr>
</table>
<table border="1" width="100%" height="227" bordercolor="#FFFFFF">
  <tr>
    <td width="10%" rowspan="8" height="223">
      <table border="0" width="100%">
        <tr>
          <td width="100%">书籍分类查询</td>
        </tr>
        <tr>
          <td width="100%"></td>
        </tr>
        <tr>
          <td width="100%"></td>
        </tr>
        <tr>
          <td width="100%"></td>
        </tr>
        <tr>
          <td width="100%"></td>
        </tr>
        <tr>
          <td width="100%"></td>
        </tr>
        <tr>
          <td width="100%"></td>
        </tr>
        <tr>
          <td width="100%"></td>
        </tr>
      </table>
    <td width="36%" rowspan="8" height="223">
      <table border="0" width="100%" bgcolor="#D8E1E8">
        <tr bgcolor="#D8E1E8">
          <td width="40%">书名</td>
          <td width="20%">作者</td>
          
          <td width="12%">出版日期</td>
          <td width="8%">价格</td>
          <td width="30%">出版社</td>
        </tr><%
int PageSize=10; //每一页显示的记录数
int ShowPage; //当前显示的页面
int RowCount; //总的记录数
int PageCount; //总的页数
java.lang.String strPage;
int i;
strPage = request.getParameter("page");
if(strPage==null){//表明在QueryString中没有page这一个参数，此时显示第一页数据
ShowPage = 1;
}
else{//将字符串转换成整型
ShowPage = java.lang.Integer.parseInt(strPage);
if(ShowPage<1) ShowPage = 1;
}
String sql=null;
String name1,accord;
int id;
name1= new String(request.getParameter("name1").getBytes("8859_1"),"GBK");
accord=new String(request.getParameter("accord").getBytes("8859_1"),"GBK");
id=Integer.parseInt(accord);
if (id==0){
out.println("<tr height='35',bgcolor='#ffffff'>");
out.println("<td>");
out.println("对不起，请选择查询方式");
out.println("</td>");
out.println("</tr>");
}
else if (name1.equals("")){
out.println("<tr height='35',bgcolor='#ffffff'>");
out.println("<td>");
out.println("对不起，查询关键字不能空!");
out.println("</td>");
out.println("</tr>");
}
if (id==1){
sql="SELECT * FROM press.bookinf where ";
sql=sql+"name like '%" +  name1 + "%'";
}
if (id==2){
sql="SELECT * FROM press.bookinf where ";
sql=sql+"press like '%" +  name1 + "%'";
}
if (id==3)
out.println("暂时不要选择此项查询");
if (sql!=null){
ResultSet rs=null;
     String DBDriver = "oracle.jdbc.driver.OracleDriver";
      String ConnStr = "jdbc:oracle:thin:@192.168.18.16:1521:press";
      Connection con = null;
      String username = "press";
      String password = "press";      Class.forName(DBDriver).newInstance();
  con = DriverManager.getConnection( ConnStr, username, password );
  try{
  Statement st= con.createStatement(java.sql.ResultSet.TYPE_SCROLL_INSENSITIVE,java.sql.ResultSet.CONCUR_READ_ONLY);
//Statement st=con.createStatement();
     rs=st.executeQuery(sql);rs.last();
RowCount=rs.getRow();
PageCount=(RowCount+PageSize-1)/PageSize;
//调整待显示的页码
if(ShowPage>PageCount) ShowPage = PageCount;
if(PageCount>0)
//将记录指针定位到待显示页的第一条记录上
rs.absolute((ShowPage-1) * PageSize + 1);
//显示数据i = 0;
String book_name,writer,translator,date,price,publish;
while(i<PageSize && !rs.isAfterLast()){rs.next();
book_name=getStr(rs.getString("name"));
writer=getStr(rs.getString("writer"));
translator=rs.getString("translator");
date=rs.getString("ndate");
publish=rs.getString("press");
price=rs.getString("price");
out.println("<td width='40%'><font size=2>"+book_name+"</font></td>");
      out.println("<td width='20%'><font size=2>"+writer+"</font></td>");
      //out.println("<td width='%'><font size=2>"+translator+"</font></td>");
      out.println("<td width='12%'><font size=2>"+date+"</font></td>");
      out.println("<td width='8%'><font size=2>"+price+"</font></td>");
      out.println("<td width='30%'><font size=2>"+publish+"</font></td>");
       out.println("</tr>");
i++;
}   }
catch(SQLException ex){
  System.out.println(ex.toString());
  }
}
%>
</td>
</table>
<%
out.println("第"+ShowPage+"页");
out.println("共"+PageCount+"页");
if (ShowPage<PageCount)
out.println("<td><a href=result.jsp?page="+ShowPage+">"+"下一页"+"</a></td>");
if (ShowPage>1)
out.println("<td><a href=result.jsp?page="+ShowPage+">"+"上一页"+"</a></td>");
%>
</table>
</html>报错如下：
org.apache.jasper.JasperException: Unable to compile class for JSPAn error occurred at line: -1 in the jsp file: nullGenerated servlet error:
    [javac] Since fork is true, ignoring compiler setting.
    [javac] Compiling 1 source file
    [javac] Since fork is true, ignoring compiler setting.
    [javac] C:\Program Files\Apache Group\Tomcat 4.1\work\Standalone\192.168.18.16\publish\jsp\result_jsp.java:287: variable PageCount might not have been initialized
    [javac] out.println("??+PageCount+"椤?);
    [javac]                 ^
    [javac] 1 error
int PageCount=0;把PageCount在定义的时候就初始化试试
[javac] C:\Program Files\Apache Group\Tomcat 4.1\work\Standalone\192.168.18.16\publish\jsp\result_jsp.java:287: variable PageCount might not have been initialized
    很显然你的pageCount没有初始化在声明的地方初始化为0应该可以的