第一步:引入依赖
<dependency><groupId>org.springframework</groupId><artifactId>spring-web</artifactId></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId></dependency>
第二步:配置tomcat(这个简单,一笔带过)
第三步:配置DispatcherServlet
官网:DispatcherServlet :: Spring Framework
点击官网,咱们会看到可以用配置类进行配置,也可以用xml的形式配置在tomcat的web.xml文件中
以代码形式配置如下:
java">public class MyWebApplicationInitializer implements WebApplicationInitializer {@Overridepublic void onStartup(ServletContext servletContext) {// Load Spring web application configurationAnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();context.register(AppConfig.class);// Create and register the DispatcherServletDispatcherServlet servlet = new DispatcherServlet(context);ServletRegistration.Dynamic registration = servletContext.addServlet("app", servlet);registration.setLoadOnStartup(1);registration.addMapping("/app/*");}
}
以xml配置如下:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"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_4_0.xsd"version="4.0"><listener><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class></listener><context-param><param-name>contextConfigLocation</param-name><param-value>classpath:app-context.xml</param-value></context-param><servlet><servlet-name>app</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class></servlet><servlet-mapping><servlet-name>app</servlet-name><url-pattern>/*</url-pattern></servlet-mapping></web-app>
咱们直接用xml配置
咱们可以看到,有一个配置文件爆红,这个我们还没写,我们先写一个app-context.xml的配置文件
其实,就是spring的配置文件,以下就是一个包扫描的配置文件
<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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsd"><context:component-scan base-package="com.example.demo.controller"/></beans>
注意还要写个app-servlet.xml,因为servlet-name是app,所以名字要搞一个app-servlet.xml,其实这个文件也是个spring的配置文件而已
<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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsd"><context:component-scan base-package="com.example.demo.controller"/></beans>
第四步:编写controller层
package com.example.demo.controller;import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;@RestController
public class HelloController {@GetMapping("/hello")public String sayHello(){return "Hello";}
}
第五步:演示结果
访问如下路径:localhost:8080/hello
第六步:其他功能
1、配置页面视图解析器
我们可以看到配置这个页面视图解析器是可以解析jsp文件的
官网关于配置视图解析器的示例:View Resolvers :: Spring Framework
咱们可以在app-servlet.xml里面编写如下代码:
<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"xmlns:mvc="http://www.springframework.org/schema/mvc"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd"><context:component-scan base-package="com.example.demo.controller"/><mvc:view-resolvers><mvc:jsp/></mvc:view-resolvers>
</beans>
点击这个mvc:jsp进去可以看到就是我们之前展示的那个视图解析器
结果展示: