beans运行出错 - J2EE论坛 - JAVA论坛

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beans运行出错

我的beans 程序是这样的
Circle.java

import java.io.*;
public class Circle
{int radius ;
public Circle()
{radius=1;
}
public int getRadius()
{return radius;
}
public void setRadius(int newRadius)
{radius=newRadius;
}
public double circleArea()
{return Math.PI*radius*radius;
}
public double circleLength()
{return 2.0*Math.PI*radius;
}
}

useBeans.jsp

<%@ page contentType="text/html;charset=GB2312" %>
<%@ page import="Circle" %>
<HTML>
<BODY begcolor=cyan>
<jsp:useBean id="girl" class="circle" scope="page" >
</jsp:useBean>
<%
girl.setRadius(100);
%>
圆的半径
<%=girl.getRadius() %>
圆的周长
<%=girl.circleLength() %>
圆的面积
<%=girl.circleArea() %>
</BODY>
</HTML>

我的useBeans.jsp放在C:\Tomcat 5.5\webapps\ROOT里
我的Circle.class放在C:\Tomcat 5.5\classes
帮我看看啊，哪里错了啊

搜索更多相关主题的帖子: beans　运行　

第 2 楼

得分:0

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: /useBeans.jsp(5,0) The value for the useBean class attribute circle is invalid.
	org.apache.jasper.servlet.JspServletWrapper.handleJspException(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: /useBeans.jsp(5,0) The value for the useBean class attribute circle 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$GenerateVisitor.visit(Generator.java:1174)
	org.apache.jasper.compiler.Node$UseBean.accept(Node.java:1116)
	org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2163)
	org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2213)
	org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2219)
	org.apache.jasper.compiler.Node$Root.accept(Node.java:456)
	org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2163)
	org.apache.jasper.compiler.Generator.generate(Generator.java:3304)
	org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:198)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:295)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:276)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:264)
	org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:563)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:303)
	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)

note The full stack trace of the root cause is available in the Apache Tomcat/5.5.16 logs.

Apache Tomcat/5.5.16

这个是运行的页面，哪里错了啊　

第 3 楼

得分:0

那useBeans.jsp是放在C:\Tomcat 5.5\webapps\ROOT是吗,
还是不行啊

拜托再帮我看看啊

exception

org.apache.jasper.JasperException: /useBeans.jsp(5,0) The value for the useBean class attribute circle is invalid.
root cause 
org.apache.jasper.JasperException: /useBeans.jsp(5,0) The value for the useBean class attribute circle is invalid
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.16 logs.

第 4 楼

得分:0

虚拟目录是什么啊
怎么建啊,
我是初学者,不懂啊

第 5 楼

得分:0

恩,我换了一个javabeans的测试程序，结果是能显示的
但是就是这个程序不对，是我从书上看的，
能不能帮我看看这个程序有什么错误啊
那个Circle我改了，可还是不对，拜托啦
<HTML>
<%@ page contentType="text/html;charset=GB2312" %>
<%@ page import="Circle"%>
<HTML>
<BODY bgcolor=cyan>
<jsp:useBean id="girl" scope="page" class="my.Circle" >
</jsp:useBean>
<%
girl.setRadius(100);
%>
圆的半径是：
<%=girl.getRadius() %>
圆的周长是：
<%=girl.circleLength() %>
圆的面积是：
<%=girl.circleArea() %>
</BODY>
</HTML>

第 6 楼

得分:0

package my;
import java.io.*;
public class Circle
{int radius ;
public Circle()
{radius=1;
}
public int getRadius()
{return radius;
}
public void setRadius(int newRadius)
{radius=newRadius;
}
public double circleArea()
{return Math.PI*radius*radius;
}
public double circleLength()
{return 2.0*Math.PI*radius;
}

}

第 7 楼

得分:0

啊啊啊,真的,我把这句
<%@ page import="Circle"%>
去掉后能运行出来了啊,
太感谢了啊

第 8 楼

得分:0

我想做个留言板,应该怎么开始啊,给我点意见啊

第 9 楼

得分:0

我在做用户注册的时候,beans里出现错误
String condition="INSERT INTO member VALUES"+"("+S+")";说找不到符号
这个句子是向数据中的member表添加记录，这样有什么不对吗

第 10 楼

得分:0

能说详细点吗，我怎么改也改不出来啊，这个是我的程序：

这个是注册的beans
package my;
import java.sql.*;
public class Register
{String logname="",
password="",
sex="",age="",
email="",
phone="",
address="",
message="";
String backNews;
Connection con;
Statement sql;
ResultSet rs;
public Register()
{try{Class.forName("sun.jdbc.odbc.jdbcodbcDriver");}
catch(ClassNotFoundException e){}
}
public void setLogname(String name)
{logname=name;
}
public String getLogname()
{return logname;
}
public void setAge(String n)
{age=n;
}
public String getAge()
{return age;
}
public void setSex(String s)
{sex=s;
}
public String getSex()
{return sex;
}
public void setPassword(String pw)
{password=pw;
}
public String getPassword()
{return password;
}
public void setEmail(String em)
{email=em;
}
public String getEmail()
{return email;
}
public void setPhone(String ph)
{phone=ph;
}
public String getPhone()
{return phone;
}
public void setAddress(String ad)
{address=ad;
}
public String getAddress()
{return address;
}
public String getMessage()
{return message;
}
public void setMessage(String m)
{message=m;
}
public String getBackNews()
{return backNews;
}
public void setBackNews(String s)
{backNews=s;
}
public void addItem()
{try{
Connection con=DriverManager.getConnection("jdbc:odbc:friend","","");
sql=con.createStatement();
if(phone.length()==0)
{phone="wu";
}
if(email.length()==0)
{email="wu"; }
if(address.length()==0)
{address="wu"; }
if(message.length()==0)
{message="wu"; }
String s=
"'"+logname+"'"+","+"'"+password+"'"+","+"'"+sex+"'"+","+
"'"+age+"'"+","+"'"+phone+"'"+","+"'"+email+"'"+","+
"'"+address+"'"+"'"+"'"+message+"'";
String condition="INSERT INTO member VALUES"+"("+S+")";
sql.executeUpdate(condition);
backNews="zhuce chenggong";
con.close();
}
catch(SQLException e)
{backNews="ni hai mei zhu ce ,qi huan mingzi ";
}
}
}

但是编译不行啊，说是String condition="INSERT INTO member VALUES"+"("+S+")";　　　找不到符号
这是什么原因啊，帮我看看啊

Apache Tomcat/5.5.16这个是运行的页面，哪里错了啊

Apache Tomcat/5.5.16

这个是运行的页面，哪里错了啊　