通过一个栗子来看看创建和运行servlet

通过前面一篇文章的介绍（搞着搞着对web project是不是有点迷糊？先关注几个问题-CSDN博客）大家对于servlet作为中间层接收请求和反馈响应有了概念上的认知，接下来通过一个栗子来加深一下理解，还是基于前面的jsp项目（Eclipse是如何创建web project项目的？-CSDN博客）继续操作，不过这篇只说一下如何创建servlet和运行访问servlet。

1、创建servlet类

输入包名和servlet类名。

此时生成的代码如下：

package com.servlet;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class TestServlet
 */
@WebServlet(description = "This is my first Servlet", urlPatterns = { "/TestServlet" })
public class TestServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

    /**
     * Default constructor. 
     */
    public TestServlet() {
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.getWriter().append("Served at: ").append(request.getContextPath());
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

我这里用的是openjdk，提示javax.servlet下面的包找不到，也就是jdk中缺少这样的class类，那么可以通过添加外部jar包到项目里面，直接导入tomcat下的jar包，如下所示：