首先利用一个html的form表单收集数据然后将数据提交给后台的servlet,servlet向客户端输入出html页面中获取的数据,可是总显示不成功。servlet编译后的class文件位于工程文件的webRoot的WEB-INF/classes中。
html页面代码如下:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Student Registration Form</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">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<h3>Student Registration Form</h3>
<form name="form1" method="get" action="/TestServlet/studentRegister">
Last Name:
<label>
<input type="text" name="LastName" id="LastName">
</label>
First Name:
<label>
<input type="text" name="FirstName" id="FirstName">
</label>
Medium Name:
<label>
<input type="text" name="MediumName" id="MediumName">
</label>
<p>Gender:
<label>
<input name="Gender" type="radio" id="Male" value="Male" checked>
Male</label>
<label>
<input type="radio" name="Gender" id="Female" value="Female">
Female</label>
</p>
<p>Major:
<label>
<select name="Major" id="Major">
<option value="CS">Computer Science</option>
<option value="Math">Mathematics</option>
<option value="EN">English</option>
<option value="CN">Chinese</option>
</select>
</label>
Minor:
<label>
<select name="Minor" size="2" multiple id="Minor">
<option>Computer Science</option>
<option>Mathematics</option>
<option>English</option>
<option>Chinese</option>
</select>
</label>
</p>
<p>Hobby:
<label>
<input name="Hobby" type="checkbox" id="Tennis" value="Tennis" checked>
Tennis</label>
<label>
<input type="checkbox" name="Hobby" id="Glof" value="Glof">
Glof</label>
<label>
<input type="checkbox" name="Hobby" id="Ping Pang" value="Ping Pang">
Ping Pan</label>
</p>
<p>Res:</p>
<p>
<label>
<textarea name="Res" cols="56" rows="3" id="Res">This is an example of an HTML form that contains text fields,radio button,combo boxs,lists,check boxes,text areas,and buttons</textarea>
</label>
</p>
<p>
<label>
<input type="submit" name="submit" id="submit" value="Submit">
</label>
<label>
<input type="submit" name="Reset" id="Reset" value="Reset">
</label>
</p>
</form>
</body>
</html>servlet源码如下:
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class studentRegister extends HttpServlet {
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out=response.getWriter();
String lastName=request.getParameter("LastName");
String firstName=request.getParameter("FirstName");
String mediumName=request.getParameter("MediumName");
String gender=request.getParameter("Gender");
String major=request.getParameter("Major");
String[] minor=request.getParameterValues("Minor");
String hobby=request.getParameter("Hobby");
String res=request.getParameter("Res");
out.println("Last Name:<b>"+ lastName+"</b> FirstName:<b>"+firstName+"</b> Medium Name:<b>"+mediumName+"</b><br>");
out.println("Gender:<b>"+gender+"</b><br>");
out.println("Major:<b>"+major+"</b> Minor:<b>");
if(minor!=null){
for(int i=0;i<minor.length;i++){
out.println(minor[i]+" ");
}
}
out.println("</b><br>");
out.println("Hobby:<b>"+hobby+"</b><br>");
out.println("Res:<b>"+res+"</b><br>");
out.close();
}}Web Project的web.xml内容如下:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>studentRegister</servlet-name>
<servlet-class>studentRegister</servlet-class>
</servlet> <servlet-mapping>
<servlet-name>studentRegister</servlet-name>
<url-pattern>/servlet/studentRegister</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>/student_Register.html</welcome-file>
</welcome-file-list>
<login-config>
<auth-method>BASIC</auth-method>
</login-config>
</web-app>
html页面代码如下:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Student Registration Form</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">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<h3>Student Registration Form</h3>
<form name="form1" method="get" action="/TestServlet/studentRegister">
Last Name:
<label>
<input type="text" name="LastName" id="LastName">
</label>
First Name:
<label>
<input type="text" name="FirstName" id="FirstName">
</label>
Medium Name:
<label>
<input type="text" name="MediumName" id="MediumName">
</label>
<p>Gender:
<label>
<input name="Gender" type="radio" id="Male" value="Male" checked>
Male</label>
<label>
<input type="radio" name="Gender" id="Female" value="Female">
Female</label>
</p>
<p>Major:
<label>
<select name="Major" id="Major">
<option value="CS">Computer Science</option>
<option value="Math">Mathematics</option>
<option value="EN">English</option>
<option value="CN">Chinese</option>
</select>
</label>
Minor:
<label>
<select name="Minor" size="2" multiple id="Minor">
<option>Computer Science</option>
<option>Mathematics</option>
<option>English</option>
<option>Chinese</option>
</select>
</label>
</p>
<p>Hobby:
<label>
<input name="Hobby" type="checkbox" id="Tennis" value="Tennis" checked>
Tennis</label>
<label>
<input type="checkbox" name="Hobby" id="Glof" value="Glof">
Glof</label>
<label>
<input type="checkbox" name="Hobby" id="Ping Pang" value="Ping Pang">
Ping Pan</label>
</p>
<p>Res:</p>
<p>
<label>
<textarea name="Res" cols="56" rows="3" id="Res">This is an example of an HTML form that contains text fields,radio button,combo boxs,lists,check boxes,text areas,and buttons</textarea>
</label>
</p>
<p>
<label>
<input type="submit" name="submit" id="submit" value="Submit">
</label>
<label>
<input type="submit" name="Reset" id="Reset" value="Reset">
</label>
</p>
</form>
</body>
</html>servlet源码如下:
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class studentRegister extends HttpServlet {
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out=response.getWriter();
String lastName=request.getParameter("LastName");
String firstName=request.getParameter("FirstName");
String mediumName=request.getParameter("MediumName");
String gender=request.getParameter("Gender");
String major=request.getParameter("Major");
String[] minor=request.getParameterValues("Minor");
String hobby=request.getParameter("Hobby");
String res=request.getParameter("Res");
out.println("Last Name:<b>"+ lastName+"</b> FirstName:<b>"+firstName+"</b> Medium Name:<b>"+mediumName+"</b><br>");
out.println("Gender:<b>"+gender+"</b><br>");
out.println("Major:<b>"+major+"</b> Minor:<b>");
if(minor!=null){
for(int i=0;i<minor.length;i++){
out.println(minor[i]+" ");
}
}
out.println("</b><br>");
out.println("Hobby:<b>"+hobby+"</b><br>");
out.println("Res:<b>"+res+"</b><br>");
out.close();
}}Web Project的web.xml内容如下:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>studentRegister</servlet-name>
<servlet-class>studentRegister</servlet-class>
</servlet> <servlet-mapping>
<servlet-name>studentRegister</servlet-name>
<url-pattern>/servlet/studentRegister</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>/student_Register.html</welcome-file>
</welcome-file-list>
<login-config>
<auth-method>BASIC</auth-method>
</login-config>
</web-app>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>studentRegister</servlet-name>
<servlet-class>studentRegister</servlet-class>
</servlet> <servlet-mapping>
<servlet-name>studentRegister</servlet-name>
<url-pattern>/servlet/studentRegister</url-pattern>
</servlet-mapping>应该是这个配置不对啊
html页面的:
<form name="form1" method="get" action="/TestServlet/studentRegister">
XML里面的:
<url-pattern>/servlet/studentRegister</url-pattern>
配置文件的问题,<form action="/TestServlet/studentRegister">
XML 里面应该和 action 一样才可以通过XML 找到对应类, 你可以先调试,再来问。
如果报的是404,就是你的页面没找到
如果是500,就是你servlet内部有问题~
HTTP Status 404 - /servlet/studentRegister--------------------------------------------------------------------------------type Status reportmessage /servlet/studentRegisterdescription The requested resource (/servlet/studentRegister) is not available.
--------------------------------------------------------------------------------Apache Tomcat/6.0.20
将form里面的action属性改为servlet/studentRegister(若html文件在web应用根目录下)
html文件位于webRoot下,编译后的servlet文件位于webRoot的WEB-INF文件夹下lib文件夹下,我也改了好的路径可就是找不到!
<utl-pattern>studentRegister</utl-pattern>
既然在action里面写了绝对路径,那么在其它地方你就得跟它匹配~
你这Server启动得不对啊,怎么是以webapps的上层目录作为根呢?WebRoot目录也不应该在URL中出现的啊。
这是错的,以前是对的,应该放classes目录下
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>HelloWorldServlet</servlet-name>
<servlet-class>cn.edu.servlet.HelloWorldServlet</servlet-class>
</servlet> <servlet-mapping>
<servlet-name>HelloWorldServlet</servlet-name>
<url-pattern>/servlet/HelloWorldServlet</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>重启Tomcat6.0,在URL栏中输入:http://localhost:8080/TestServlet/servlet/HelloWorldServlet
提示错误如下:HTTP Status 404 - /webapps/TestServlet/servlet/HelloWorldServlet--------------------------------------------------------------------------------type Status reportmessage /webapps/TestServlet/servlet/HelloWorldServletdescription The requested resource (/webapps/TestServlet/servlet/HelloWorldServlet) is not available.
(我已经在环境变量中配置好了CLASSPATH路径了,在改路径中加入了servlet-api.jar了)
敬请各位大侠指点,它已经困扰我一天了,痛苦啊!
比如web.xml中servlet定义如下:
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>studentRegisterServlet</servlet-name>
<servlet-class>cn.edu.servlet.studentRegisterServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>HelloWorldServlet</servlet-name>
<url-pattern>/HelloWorldServlet</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>studentRegisterServlet</servlet-name>
<url-pattern>/servlet/studentRegisterServlet</url-pattern>
</servlet-mapping>
那么你的form表单中的action就是action=“/servlet/studentRegisterServlet”;
这样的话,Tomcat会自动帮你映射到classes文件夹中的对应的servlet中去。