Question

我正在运行Tomcat v7.0。我正在努力学习Servlets。我试过使用以下代码：

我试图纠正被叫网址。然后我删除了我的项目并创建了一个新项目。但错误仍然相同，＆＃34; Http 404＆＃34;。如何使用＆＃34; Servlet＆＃34;更正被调用的URL或生成Servlet。接口？Either the called URL is wrong or maybe the code is wrong!

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.Servlet;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebServlet;

@WebServlet("/Hello2")
public class Hello2 implements Servlet {
    ServletConfig config = null;

    public Hello2() {
        super();
    }
    @Override
    public void destroy() {
        System.out.println("Servlet is destroyed!");
    }
    @Override
    public ServletConfig getServletConfig() {
        return config;
    }
    @Override
    public String getServletInfo() {
        return "Copyright 2017-2018";
    }
    @Override
    public void init(ServletConfig config) throws ServletException {
        this.config = config;
        System.out.println("Servlet is initialized!");
    }
    @Override
    public void service(ServletRequest req, ServletResponse res)
            throws ServletException, IOException {
        res.setContentType("text/html");
        PrintWriter out = res.getWriter();

        out.println("<html>");
        out.println("<head>");
        out.println("<title>");
        out.println("Hello2");
        out.println("</title>");
        out.println("</head>");
        out.println("<body>");
        out.println("<h2>Hello Hello!!</h2>");
        out.println("</body>");
        out.println("</html>");

        out.close();
    }
}

我尝试使用web.xml更改调用URL 这是我的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" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" 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>SDM</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>
</web-app>
<servlet-mapping>
    <servlet-name>Hello2</servlet-name>
    <url-pattern>/SDM</url-pattern>
</servlet-mapping>

如何使用界面＆＃34; Servlet＆＃34;？制作基本的Servlet？

0 个答案: