Spring-13-监听器

格外加入三个依赖

<!-- servlet依赖 -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.1.0</version>
      <scope>provided</scope>
    </dependency>
    <!-- jsp依赖 -->
    <dependency>
      <groupId>javax.servlet.jsp</groupId>
      <artifactId>jsp-api</artifactId>
      <version>2.2.1-b03</version>
      <scope>provided</scope>
    </dependency>

    <!--为了使用监听器对象，加入依赖-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>5.2.5.RELEASE</version>
    </dependency>
  </dependencies>

更改web版本，

不用注解

实例化

Servlet的内容

package com.bjpowernode.controller;

import com.bjpowernode.domain.Student;
import com.bjpowernode.service.StudentService;
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 javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class RegisterServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        String strId = request.getParameter("id");
        String strName = request.getParameter("name");
        String strEmail = request.getParameter("email");
        String strAge = request.getParameter("age");

        //创建spring的容器对象
        //String config= "spring.xml";
        //ApplicationContext ctx = new ClassPathXmlApplicationContext(config);
        WebApplicationContext ctx = null;
        //获取ServletContext中的容器对象，创建好的容器对象，拿来就用
        /*String key =  WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE;
        Object attr  = getServletContext().getAttribute(key);
        if( attr != null){
            ctx = (WebApplicationContext)attr;
        }*/

        //使用框架中的方法，获取容器对象
        ServletContext sc = getServletContext();
        ctx = WebApplicationContextUtils.getRequiredWebApplicationContext(sc);
        System.out.println("容器对象的信息========"+ctx);

        //获取service
        StudentService service  = (StudentService) ctx.getBean("studentService");
        Student student  = new Student();
        student.setId(Integer.parseInt(strId));
        student.setName(strName);
        student.setEmail(strEmail);
        student.setAge(Integer.valueOf(strAge));
        service.addStudent(student);

        //给一个页面
        request.getRequestDispatcher("/result.jsp").forward(request,response);

    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    }
}

使用监听器

web.xml注册监听器