新人初学，卡在起点~Jsp的小问题
我是刚刚入手的JSP，按照教材编写简单的Bean测试，主要通过对“用户名”、“密码”和“年龄”的设置和查询练习对Bean的操作，却遇到了很大的问题，希望大家不吝赐教。
使用JDK 6+Tomcat 5.0.28+NetBeans 5.5进行开发。
源代码如下：
/**
TestBean.java
*/
package com.jspdev.ch3;
public class TestBean
{
public String userName;
public String password;
public int age;
public void setUserName(String name)
{
this.userName=name;
}
public void setPassword(String passwordTemp)
{
this.password=passwordTemp;
}
public String getUserName()
{
return this.userName;
}
public String getPassword()
{
return password;
}
public int getAge()
{
return this.age;
}
public void setAge(int ageTemp)
{
this.age=ageTemp;
}
}
/**
TestBean.java 结束
*/
/**
register.jsp
*/
<%@ page contentType= "text/html;charset=gb2312 "%>
<jsp:useBean id= "user " scope= "page " class= "com.jspdev.ch3.TestBean "/>
<jsp:setProperty name= "user " property= "* "/>
<html>
<body>
注册成功： <br>
<hr>
使用bean属性方法： <br>
用户名： <%=user.getUserName() %> <br>
密码： <%=user.getPassword() %> <br>
年龄： <%=user.getAge() %> <br>
<hr>
使用getProperty: <br>
用户名： <jsp:getProperty name= "user " property= "userName "/> <br>
密码： <jsp:getProperty name= "user " property= "password "/> <br>
年龄： <jsp:getProperty name= "user " property= "age "/> <br>
</body>
</html>
/**
register.jsp 结束
*/
/**
regiester.html
*/
<html>
<body>
用户信息注册： <br> <hr>
<form method= "get " action= "register.jsp ">
<table>
<tr> <td> 姓名： <input name= "userName " type= "text "> </td> </tr>
<tr> <td> 密码： <input name= "password " type= "password "> </td> </tr>
<tr> <td> 年龄: <input name= "age " type= "text "> </td> </tr>
<tr> <td> <input type=submit value= "submit "> </td> </tr>
</table>
</form>
</body>
</html>
/**
regiester.html 结束
*/
但是无论直接通过IE运行还是NetBeans编译，register.jsp始终通过不过编译。
在NetBeans中报错：
compile-single-jsp:
Duplicated project name in import. Project Register-impl defined first in C:\Documents and Settings\Java\Register\nbproject\ant-deploy.xml and again in C:\Documents and Settings\Java\Register\nbproject\build-impl.xml
init:
deps-module-jar:
deps-ear-jar:
deps-jar:
library-inclusion-in-archive:
library-inclusion-in-manifest:
compile:
org.apache.jasper.JasperException: The value for the useBean class attribute com.jspdev.ch3.TestBean is invalid.
C:/Documents and Settings/Java/Register/build/web/register.jsp(2,0)
C:\Documents and Settings\Java\Register\nbproject\build-impl.xml:372: The following error occurred while executing this line:
C:\Documents and Settings\Java\Register\nbproject\build-impl.xml:353: Java returned: 1
生成失败（总时间：1 秒）
如果在IE中，运行regiester.html，提交完表单，就会报错：
HTTP Status 500
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: /register.jsp(2,0) The value for the useBean class attribute com.jspdev.ch3.TestBean 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)
org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:368)
root cause
org.apache.jasper.JasperException: /register.jsp(2,0) The value for the useBean class attribute com.jspdev.ch3.TestBean 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:3305)
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)
org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:368)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.17 logs.
1.问题出现在什么地方呢？我直接使用光盘上的范例程序也还是会出现这样的情况。为什么？有谁可以告诉我么？
2.另外还有一个问题，我根据书上的范例程序，把TestBean.java放进了WEB-INF/classes这个文件夹里面，可是从代码上看，好像放在什么文件夹里面没有什么关系啊，不过我不能验证，因为通不过编译，都没有办法调用TestBean.java。
3.在TestBean.java中，“package com.jspdev.ch3”这一句是打包对么？这句有什么作用？难道不是对应的相应文件夹么？
------解决方案--------------------
原因是你的TestBean.java没有编译成.class文件
编译后把TestBean.class放到WEB-INF/classes/com/jspdev/ch3下
[解决办法]
package com.jspdev.ch3
这句话的意思是，包名是“com.jspdev.ch3”
所以你工程里的包名也必须是这个，否则会找不到包，而出错的。
我的异常网推荐解决方案：The server encountered an internal error () that prevented it from fulfilling this request.,http://www.myexception.cn/java-web/317.html
