web项目中的spring容器注入servlet——使用工具

1、servlet

package com.servlets;

import com.beans.Student;
import com.service.IStudentService;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;

import java.io.IOException;

/**

• @author dc

• @date 2020/4/3 - 14:42
  */
  public class RegisterServlet extends javax.servlet.http.HttpServlet {
  protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {

   request.setCharacterEncoding("utf-8");
   String name = request.getParameter("name");
   String ageStr = request.getParameter("age");
   Integer age = Integer.valueOf(ageStr);
   Student student = new Student();
   student.setName(name);
   student.setAge(age);
  
   // System.out.println(student);
  
   //获取spring容器
   WebApplicationContext ac = WebApplicationContextUtils.getRequiredWebApplicationContext(getServletContext());
   System.out.println(ac);
  
   //获取service对象
   IStudentService service = (IStudentService) ac.getBean("myService");
  
   //将调用dao层方法学生对象插入到数据库
   service.addStudent(student);
  
   request.getRequestDispatcher("/welcome.jsp").forward(request, response);
  

  }

  protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
  doPost(request, response);
  }
  }

2、web.xml

<?xml version="1.0" encoding="UTF-8"?>

<!--指定spring配置文件的名称及位置-->
<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:applicationContext.xml</param-value>
</context-param>

<!--注册listener-->
<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

<!--注册registerServlet-->
<servlet>
    <servlet-name>RegisterServlet</servlet-name>
    <servlet-class>com.servlets.RegisterServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>RegisterServlet</servlet-name>
    <url-pattern>/registerServlet</url-pattern>
</servlet-mapping>