到底要怎样调用JAVABEAN才正确呢??

最好把Conn.executeQuery("select * from test")放到业务层去做,不要在JSP中做,然后把取得的值放入BEAN中,在JSP中显示出来!

头一次弄JSP,麻烦bluesky35(蓝天) 给我个实例好吗^_^,谢谢啦!

********************javabean(formpath.user.class):********************
private String txt_username = "";//取得用户名
public String gettxt_username(){
return this.txt_username;
}//存放用户名
public void settxt_username(String txt_username){
this.txt_username = txt_username;
}********************action中********************
public ActionForward doAction(ActionMapping mapping,
                                        ActionForm form,
                                        HttpServletRequest request,
                                        HttpServletResponse response)
                             throws IOException,ServletException {
    ...................
    Conn.executeQuery("select username from test");
    user userForm = (user)(form);
    userForm.settxt_username(Conn.getString("username"));
    request.setAttribute("userForm",userForm);
    return (mapping.findForward("success"));
}********************Jsp中********************
<HEAD>
<jsp:useBean id="userForm" scope="request" class="formpath.user" />
//.......
<%=userForm.gettxt_username()%>
</jsp:userBean>//以上是我临时写的一个实例,大致情况是这样,在action中取得数据库数据,放在bean里传到jsp页面上显示!

那么如果按我的方法要怎么写才对呢:
<%@ page contentType="text/html; charset=GBK" %>
<%@ page import="java.sql.*" %>
<jsp:useBean id="Conn" scope="page" class="SqlConn.Conn"/><%=Conn.executeQuery("select * from test")%>
到底要怎样调用JAVABEAN才正确显示表test的内容呢????
-------------------------------------------------

你这样应该已经就可以执行了，
好像是jdbc没有装好吧

你写的这个Bean问题太多.建立顺序:
1 Connection conn
2 Statement stmt
3 ResultSet rs关闭顺序与建立顺序相反,否则结果集无效!

我都装好啦,因为我不用JAVABEAN连数据库都测试好啦的!

返回ResultSet对象可以直接调用<%=>去显示？？头一次听说 sigh

<%@ page contentType="text/html; charset=GBK" %>
<%@ page import="java.sql.*" %>
<jsp:useBean id="Conn" scope="page" class="SqlConn.Conn"/>
<%
String sql="select * from test";
ResultSet rs = Conn.executeQuery(sql);
while(rs.next()) {%> test1:<%=rs.getString(2)%><br>
test2:<%=rs.getString(3)%>
<%}%>
----------------------------------------------------------
我这样来测试,怎么还是有错,郁闷!!!!!!!111

错误提示:
type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:358)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
root cause java.lang.NullPointerException
org.apache.jsp.jsp.index_jsp._jspService(index_jsp.java:58)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:133)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:311)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856

我刚才开始学JSP.按实例来弄了一个javabean 弄了一个星期都没成功.想跳楼了....

是不是bean放置的位置不正确，我也是新手，也遇到过这样的问题。

刚测试啦一下,怀疑是Servlet和JavaBean的环境没配置好
在Tomcat下JSP、Servlet和JavaBean到底要怎样配置环境变量. Servlet和JavaBean才能正常运行呢.刚才网上搜啦一把,没一个可以配置好的,郁闷!!!!!!!!!!!1111

搂住需要理解一下java object的含义：
Object o;
System.println(o) == System,println(o.toString())
所以输出为Resultset的名字

调试易

到底要怎样调用JAVABEAN才正确呢??

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