SpringMVC基础

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

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
version="3.1">

    dispatcherServlet
    org.springframework.web.servlet.DispatcherServlet

    
        contextConfigLocation
        classpath:spring-mvc.xml
    



    dispatcherServlet
    /

Spring-mvc.xml

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

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}