SpringMVC基础

来千锋学习的第19天
SpringMVC基础
概念
SpringMVC简介
配置
添加依赖 Spring-webmvc（4.3.6）八个jar包添加进来
配置web.xml文件: 让所的/请求都交给了我DispatcherServlet，而DispatcherServlet里面需要配置一个contextConfigLocation，上下文配置路径，也就是我们的SpringMVC的配置文件。如果没有显式地配置该属性，SpringMVC会在默认WEB-INF下去找[servlet-name]-servlet.xml文件

    
        dispatcherServlet
        org.springframework.web.servlet.DispatcherServlet

        
            contextConfigLocation
            classpath:spring-mvc.xml
        
    

    
        dispatcherServlet
        /
    

Spring-mvc.xml




    
    
        
        
    

    
    

    
    
    

ProductInputController.java

package com.qfedu.controller;


import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.Controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * SpringMVC配置文件中让/ProductInput请求会交给当前类来进行处理，自动执行Controller的回调方法
 */
public class ProductInputController implements Controller {

    /**
     * /ProductInput请求会回调该方法
     * 
     * @param request
     * @param response
     * @return  视图和模型对象，只需要展示页面，则需要一个单纯的虚拟视图名即可
     * @throws Exception
     */
    @Override
    public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
        //return new ModelAndView("/WEB-INF/view/index.jsp");
        return new ModelAndView("index.html");
    }
}

index.html




    
    


this is product input html page.


    pid:

    pname:

    price:

    

在当前的表单页面上输入信息提交，交给一个新的请求/SaveProductController，那么发出一个新的请求，先交给DispatcherServlet，然后读取SpringMVC配置文件，发现该请求交给了SaveProductController控制器

package com.qfedu.controller;

import com.qfedu.bean.Product;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.Controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class SaveProductController implements Controller {
    @Override
    public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {


        String spid = request.getParameter("pid");
        String pname = request.getParameter("pname");
        String sprice = request.getParameter("price");

        int pid = spid == null ? 0 : Integer.parseInt(spid);
        double price = sprice==null ? 0.0 : Double.parseDouble(sprice);

        Product p = new Product();

        p.setPid(pid);
        p.setPname(pname);
        p.setPrice(price);

        /**
         * 创建模型视图对象
         *  该代码等同于以前的两行代码
         *          request.setAttribute("p", p);
         *          request.getRequestDispatcher("detail.jsp").forward(request, response);
          */
        ModelAndView mv = new ModelAndView("detail.jsp", "p", p);


        return mv;
    }
}

detail.jsp

<%--
  Created by IntelliJ IDEA.
  User: james
  Date: 2020/3/3
  Time: 11:27 AM
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>


    


    
this is product detail page.

    
pid : ${p.pid}
    
pname : ${p.pname}
    
price : ${p.price}

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