初学者问题,我的类执行编译通过了，为什么还出现错误???？？？？高分!~!

change name="checkbox" to name="fond":<input type="checkbox" name="fond" value="1">旅游
<input type="checkbox" name="fond" value="2">体育
<input type="checkbox" name="fond" value="3">音乐
<input type="checkbox" name="fond" value="4">摄影

解决方案 »

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换过了，还是那样
<html>
<head>
<title>无标题文档</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
</head><body bgcolor="#FFFFFF" text="#000000">
<form name="form" method="get" action="http://yu.40it.com/servlet/formGetExample">
<table width="100%" border="0" cellspacing="0" cellpadding="0" height="213">
  <tr>
    <td>昵称:</td>
    <td>
      <input type="text" name="nickname">
    </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
  </tr>
  <tr>
    <td>密码:</td>
    <td>
      <input type="password" name="password">
    </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
  </tr>
  <tr>
    <td>确认密码:</td>
    <td>
      <input type="password" name="password2">
    </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
  </tr>
  <tr>
    <td>性别:</td>
    <td>
      <input type="radio" name="gender" value="man">
      男
      <input type="radio" name="gender" value="woman">
      女
      <input type="radio" name="gender" value="noman" checked>
      保密</td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
  </tr>
  <tr>
<td>
<input type="checkbox" name="fond" value="1">旅游
<input type="checkbox" name="fond" value="2">体育
<input type="checkbox" name="fond" value="3">音乐
<input type="checkbox" name="fond" value="4">摄影</td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
  </tr>
  <tr>
    <td>地区:</td>
    <td>
      <select name="select" size="1">
        <option value="1">北京</option>
        <option value="2">上海</option>
        <option value="3">重庆</option>
        <option value="4">天津</option>
        <option value="5">其他</option>
      </select>
    </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
  </tr>
  <tr>
    <td>隐藏淤:</td>
    <td>
      <input type="hidden" name="hidden" value="hidden example">
      <input type="submit" name="Submit" value="确定">
      <input type="reset" name="reset" value="重写">
    </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
    <td> </td>
  </tr>
</table></form>
</body>
</html>
<select name="select" size="1">
==>
<select name="area" size="1">
1.response.setContentType("text/html;charset=gb2312");
2. String area = request.getParameter("area");
===>
String area = request.getParameter("area");
if (area == null)
  area = "";
我是这样做的
import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class formGetExample extends HttpServlet{
public void doGet(HttpServletRequest request,HttpServletResponse response)
                  throws IOException, ServletException
{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<html>");
out.println("<body bgcolor=\"white\">");
out.println("<head>");
out.println("<title>Servlet GET Example</title>");
out.println("</head>");
out.println("<body>");
out.println("<h1>Servlet Get Example</h1>");
String gender = request.getParameter("gender");
String value = "";
if (gender.equals("1"))
{
value="男";
} else if (gender.equals("2"))
{
value = "女";
} else {
value = "保密";
}
value = "姓别 = " + value;
String value3 = new String(value.getBytes("gb2312"),"8859_1");
out.println(value3);
out.println("<br>");
String fonds[] = request.getParameterValues("fond");
value = "";
for (int i=0;i<fonds.length;i++ )
{
if (fonds[i].equals("1"))
{
value = value + "旅游、";
}else if(fonds[i].equals("2")){
value = value + "体育、";
} else if (fonds[i].equals("3"))
{
value = value + "音乐、";
} else if (fonds[i].equals("4"))
{
value = value + "摄影";
}
}
value = "爱好 = " + value; String value2 = new String(value.getBytes("gb2312"),"8859_1");
out.println(value2);
out.println("<br>");
String area = request.getParameter("area");
value = "";
if (area.equals("1"))
{
value = "地区 = 北京";
} else if (area.equals("2"))
{
value = "地区 = 上海";
} else if (area.equals("3"))
{
value = "地区 = 重庆";
}else if (area.equals("4"))
{
value = "地区 = 天津";
} else {
value = "地区 = 其他";
}
String value1=new String(value.getBytes("gb2312"),"8859_1");
out.println(value1);
out.println("<br>");
out.println("</body>");
out.println("</html>");
out.close();
}
}
good, check if possible null values for gender, fonds, area