目录结构：

webapps＆gt;简单程序（包含Servlet和JSP文件）＆gt; WEB_INF（包含web.xml）＆gt; classes（包含类）

Servlet：ServletClassCalled

import java.io.IOException;
import javax.servlet.http.*;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.annotation.WebServlet;
import java.io.*;
import java.io.PrintWriter;
import java.util.*;

@WebServlet("/ServletClassCalled")
public class ServletClassCalled extends HttpServlet {

    private static final long serialVersionUID = 1L;

    public void doGet (HttpServletRequest request,HttpServletResponse response) throws IOException {
        response.setContentType("text/html");
        PrintWriter pw = response.getWriter();
        String username = request.getParameter("username");
        String chkValues[] = request.getParameterValues("chk1");
        pw.write("Success");
        pw.write(username);
        pw.write("Chk Val 1 "+chkValues[0]+" Chk Val 2 "+chkValues[1]);
    }
    public void doPost (HttpServletRequest request,HttpServletResponse response) throws IOException {
        response.setContentType("text/html");

        PrintWriter out = response.getWriter();
        Enumeration headerNames = request.getHeaderNames();
        while(headerNames.hasMoreElements()) {
        String paramName = (String)headerNames.nextElement();
        out.print(paramName);
        String paramValue = request.getHeader(paramName);
        out.println(paramValue);
        }
    }
}

JSP：index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Insert title here</title>
</head>
<body>
<h1>Simple App</h1>
<form method="get" action="ServletClassCalled">
    User Name : <input type="text" name="username" /><br/>
    Hobbies: <input type="checkbox" name="chk1" value="Coding" /> Coding <input type="checkbox" name="chk1" value="Sleeping" /> Sleeping<br/>
    <input type="submit" name="submit" value="submit" />
</form>
<hr/>
<form method="post" action="ServletClassCalled">
    <input type="submit" name="submit" value="submit" />
</form>
</body>
</html>

部署描述符：web.xml

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app 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_3_0.xsd"
  version="3.0"
  metadata-complete="true">

    <!-- Define servlets that are included in the example application -->
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
    <servlet>
      <servlet-name>ServletClassCalled</servlet-name>
      <servlet-class>ServletClassCalled</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>ServletClassCalled</servlet-name>
        <url-pattern>/ServletClassCalled</url-pattern>
    </servlet-mapping>
    <servlet>
      <servlet-name>GetHeader</servlet-name>
      <servlet-class>GetHeader</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>GetHeader</servlet-name>
        <url-pattern>/GetHeader</url-pattern>
    </servlet-mapping>
</web-app>

由于我在欢迎列表中列出了索引文件，因此它显示正确但当我尝试提交表单时显示错误。

Servlet Error

Answer 1

我忘了在web.xml中关闭我的标签。现在工作正常。

Answer 2

对于更新的Servlet 3.0版它提供了使用包

在内部映射servlet的功能

javax.servlet.annotation.WebServlet;

还会生成servlet路径的自动生成代码

@WebServlet（＆＃34; / ServletClassCalled＆＃34）

因此，如果您使用的是servlet 3.0，则无需在web.xml文件中编写servlet的映射

Servlet错误：请求的资源不可用

目录结构：

webapps＆gt;简单程序（包含Servlet和JSP文件）＆gt; WEB_INF（包含web.xml）＆gt; classes（包含类）

2 个答案: