使用javabean超级简单问题
javabean代码:
public class Counter
{
//public long count=0;
//public String Name;
public String GetPower(int i)
{
if(i> 0)
{
return "> 0 ";
}
else
{
return " <0 ";
}
}
}
jsp代码:
<%@ page contentType= "text/html;charset=GB2312 " %>
<jsp:useBean id= "counter " class= "Counter " scope= "application ">
</jsp:useBean>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN ">
<html>
<head>
<title> My JSP 'index.jsp ' starting page </title>
<meta http-equiv= "pragma " content= "no-cache ">
<meta http-equiv= "cache-control " content= "no-cache ">
<meta http-equiv= "expires " content= "0 ">
<meta http-equiv= "keywords " content= "keyword1,keyword2,keyword3 ">
<meta http-equiv= "description " content= "This is my page ">
</head>
<body>
This is my JSP page. <br>
<%=counter.GetPower(1)%>
</body>
</html>
输出总出错:
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: /index.jsp(2,0) The value for the useBean class attribute Counter is invalid.
org.apache.jasper.servlet.JspServletWrapper.handle
JspException(JspServletWrapper.java:510)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:375)
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)
root cause
org.apache.jasper.
JasperException: /index.jsp(2,0) The value for the useBean class attribute Counter is invalid.
org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:39)
org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:405)
org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:146)
org.apache.jasper.compiler.Generator$GenerateVisitor.visit(Generator.java:1174)
org.apache.jasper.compiler.Node$Us