javaee自定义servlet的步骤

1、必须继承HttpServlet类

package com.azhi.servlet;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class LoginServlet extends HttpServlet{
    private static final long serialVersionUID = 1L;
    
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("doGet");
    }
    
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("doPost");
    }

}

2、必须在web.xml上注册自定义的servlet

 <!-- 注册servlet -->
  <servlet>
      <servlet-name>loginServlet</servlet-name>
      <servlet-class>com.azhi.servlet.LoginServlet</servlet-class>
  </servlet>
  <!-- 映射servlet -->
  <servlet-mapping>
      <servlet-name>loginServlet</servlet-name>
      <url-pattern>/login</url-pattern>
  </servlet-mapping>