这是zs类,主要是连接数据库和一些简单的操作。
import java.util.*;
import java.io.*;
import java.sql.*;public class foodzs{
Connection conn;
Statement stmt;
ResultSet rs;
String url ="jdbc:mysql://localhost:3306/index?user=root&password=123456&useUnicode=true&characterEncoding=8859_1" ;
stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
String sql="select * from homepage";
rs=stmt.executeQuery(sql);public void foodzs(){
try
{
Class.forName("org.gjt.mm.mysql.Driver").newInstance();
conn= DriverManager.getConnection(url);
}
catch(Exception e){
e.printStackTrace();
}
} public void nextip()
{
rs.next();
}public void closedata()
{
rs.close();
stmt.close();
conn.close();
}
}很简单一个类实体,为什么会显示下面的错误啊。D:\Tomcat 5.5\webapps\myapp\WEB-INF\classes>javac foodzs.java
foodzs.java:10: <identifier> expected
stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDAT
ABLE);
^
foodzs.java:12: <identifier> expected
rs=stmt.executeQuery(sql);
^
2 errorsD:\Tomcat 5.5\webapps\myapp\WEB-INF\classes>
import java.util.*;
import java.io.*;
import java.sql.*;public class foodzs{
Connection conn;
Statement stmt;
ResultSet rs;
String url ="jdbc:mysql://localhost:3306/index?user=root&password=123456&useUnicode=true&characterEncoding=8859_1" ;
stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
String sql="select * from homepage";
rs=stmt.executeQuery(sql);public void foodzs(){
try
{
Class.forName("org.gjt.mm.mysql.Driver").newInstance();
conn= DriverManager.getConnection(url);
}
catch(Exception e){
e.printStackTrace();
}
} public void nextip()
{
rs.next();
}public void closedata()
{
rs.close();
stmt.close();
conn.close();
}
}很简单一个类实体,为什么会显示下面的错误啊。D:\Tomcat 5.5\webapps\myapp\WEB-INF\classes>javac foodzs.java
foodzs.java:10: <identifier> expected
stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDAT
ABLE);
^
foodzs.java:12: <identifier> expected
rs=stmt.executeQuery(sql);
^
2 errorsD:\Tomcat 5.5\webapps\myapp\WEB-INF\classes>
String sql="select * from homepage";
rs=stmt.executeQuery(sql);这两个调用方法怎么放在方法外?
<%Class.forName("org.gjt.mm.mysql.Driver").newInstance();
String url ="jdbc:mysql://localhost/softforum?user=soft&password=123456&useUnicode=true&characterEncoding=8859_1" ;
Connection conn= DriverManager.getConnection(url);
Statement stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
String sql="select * from first";
ResultSet rs=stmt.executeQuery(sql);
%>后面是JSP页面代码,其中在输出的地方我用
<tr>
<td bgcolor="#FFFFFF"><div align="center"><%=rs.getString(2)%></div></td>
</tr>
提取数据库第2个字段内容,为什么显示下面这段代码?
javax.servlet.ServletException: Before start of result set
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:848)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:781)
org.apache.jsp.indexzs_jsp._jspService(org.apache.jsp.indexzs_jsp:599)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
下面就是结束数据库了。
<%
rs.close();
stmt.close();
conn.close();
%> 请高手指点谢谢...急啊~~~~~~~~~~
),我在别的地方都好使,最好再说仔细点。谢谢
rs.next();
或者
rs.last();