环境
IDE：idea 2020.3
构建工具：maven-3.8.1
服务器：tomcat9
Spring版本：5.3.1
<dependencies>
<!-- SpringMVC -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>5.3.1</version>
</dependency>
<!-- 日志 -->
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.2.3</version>
</dependency>
<!-- ServletAPI -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
<scope>provided</scope>
</dependency>
<!-- Spring5和Thymeleaf整合包 -->
<dependency>
<groupId>org.thymeleaf</groupId>
<artifactId>thymeleaf-spring5</artifactId>
<version>3.0.12.RELEASE</version>
</dependency>
</dependencies>
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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/context https://www.springframework.org/schema/context/spring-context.xsd">
<!-- springMVC.xml -->
<!-- 自动扫描包 -->
<context:component-scan base-package="com.fly.controller"/>
<!-- 配置Thymeleaf视图解析器 -->
<bean id="viewResolver" class="org.thymeleaf.spring5.view.ThymeleafViewResolver">
<property name="order" value="1"/>
<property name="characterEncoding" value="UTF-8"/>
<property name="templateEngine">
<bean class="org.thymeleaf.spring5.SpringTemplateEngine">
<property name="templateResolver">
<bean class="org.thymeleaf.spring5.templateresolver.SpringResourceTemplateResolver">
<!-- 视图前缀 -->
<property name="prefix" value="/WEB-INF/templates/"/>
<!-- 视图后缀 -->
<property name="suffix" value=".html"/>
<property name="templateMode" value="HTML5"/>
<property name="characterEncoding" value="UTF-8" />
</bean>
</property>
</bean>
</property>
</bean>
</beans>
<!-- web.xml -->
<filter>
<filter-name>CharacterEncodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
<init-param>
<param-name>forceResponseEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>CharacterEncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<servlet>
<servlet-name>DispatcherServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:springMVC.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>DispatcherServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
request
ServletAPI
package com.fly.mvc.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import javax.servlet.http.HttpServletRequest;
/**
* @author 26414
*/
@Controller
public class IndexController {
@RequestMapping("/")
public String index() {
return "index";
}
@RequestMapping("/testServlet")
public String testServlet(HttpServletRequest request) {
request.setAttribute("testScope","servlet");
return "hello";
}
}
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>首页</title>
</head>
<body>
<!--index.html-->
<a th:href="@{/testServlet}">通过ServletAPI向request存放数据</a>
</body>
</html>
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>hello</title>
</head>
<body>
<!--hello.html-->
<h2>hello</h2>
<p th:text="${testScope}"></p>
</body>
</html>
ModelAndView
/**
*IndexController
*/
@RequestMapping("/testModelAndView")
public ModelAndView testModelAndView(ModelAndView modelAndView) {
//向请求域共享数据
modelAndView.addObject("testScope","ModelAndView");
//设置视图
modelAndView.setViewName("hello");
return modelAndView;
}
<!--index.html-->
<a th:href="@{/testModelAndView}">通过ModelAndView向request存放数据</a>
Model
/**
*IndexController
*/
@RequestMapping("/testModel")
public String testModel(Model model) {
model.addAttribute("testScope","model");
return "hello";
}
<!--index.html-->
<a th:href="@{/testModel}">通过Model向request存放数据</a><br/>
map
/**
*IndexController
*/
@RequestMapping("/testMap")
public String testMap(Map<String,Object> map) {
map.put("testScope","map");
return "hello";
}
<!--index.html-->
<a th:href="@{/testMap}">通过Map向request存放数据</a><br/>
ModelMap
/**
*IndexController
*/
@RequestMapping("/testModelMap")
public String testModelMap(ModelMap map) {
map.put("testScope","modelMap");
return "hello";
}
<!--index.html-->
<a th:href="@{/testModelMap}">通过ModelMap向request存放数据</a><br/>
Model、ModelMap、Map的关系
在控制台打印这三个对象的信息
可以发现这三个对象都是BindingAwareModelMap类型的
在几个方法上打断点，用debug模式启动服务器，访问/testServlet，可以在方法栈中看到前端控制器的方法
F9跳过这个断点，进入下一个断点，可以发现数据被封装到一个ModelAndView上
访问/testModelAndView
访问/testModel
最后得出结论，使用Model、ModelMap、Map最后数据都会封装到ModelAndView上
session
/**
*IndexController
*/
@RequestMapping("/testSession")
public String testSession(HttpSession session) {
session.setAttribute("testSessionInfo","session");
return "hello";
}
<!--index.html-->
<a th:href="@{/testSession}">通过ServletAPI向session存放数据</a><br/>
<!--hello.html-->
<p th:text="${session.testSessionInfo}"></p>
application
/**
*IndexController
*/
@RequestMapping("/testApplication")
public String testApplication(HttpSession session) {
ServletContext application = session.getServletContext();
application.setAttribute("testApplicationInfo","application");
return "hello";
}
<!--index.html-->
<a th:href="@{/testApplication}">通过ServletAPI向application存放数据</a><br/>
<!--hello.html-->
<p th:text="${application.testApplicationInfo}"></p>