如何使用eclipse kepler和Apache7制作和运行servlet

Question

我正在制作这个新的servlet：

package Servlets;

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;

/**
 * Servlet implementation class Hello
 */
public class Hello extends HttpServlet
{
    private static final long   serialVersionUID    = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public Hello()
    {
        super();
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
    {
        response.setContentType("text/html");

        PrintWriter out = response.getWriter();
        out.println("It works");
        out.close();
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
    {
        doGet(request, response);
    }

}

这是我在WEB-INF中的web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>FirstServlet</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>

   <servlet>
      <servlet-name>Hello</servlet-name>
      <servlet-class>Hello</servlet-class>
   </servlet>

   <servlet-mapping>
      <servlet-name>Hello</servlet-name>
      <url-pattern>/hello</url-pattern>
   </servlet-mapping>
</web-app>

创建动态web项目时，会自动生成display-name和welcome-file-list标记。servlet和servlet映射由我编写。当我使用Appache7运行项目时，它显示HTTP status404-/firstservlet/。我的错在哪里？

Answer 1

1）您可能缺少列出的所有欢迎文件。404是当没有文件时应该发生的情况。

2）servlet映射被破坏。servlet-class元素需要一个完全限定的类名，它应该是servlets.hello而不是仅仅hello。当正确映射时，/firstservlet/hello将到达您的servlet，匹配映射的URI，然后根据名称找到注册的servlet，最后到达应该执行的完全限定的类。