Spring in Action（五）：基于Java Config的SpringMVC

1、搭建SpringMVC项目

可参考搭建Spring项目教程：http://blog.csdn.net/lom9357bye/article/details/72796668

pom文件如下

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">    <modelVersion>4.0.0</modelVersion>    <groupId>com.learning</groupId>    <artifactId>springmvc-learning</artifactId>    <packaging>war</packaging>    <version>1.0-SNAPSHOT</version>    <name>springmvc-learning Maven Webapp</name>    <url>http://maven.apache.org</url>    <dependencies>        <!--使用单元测试所需jar包-->        <dependency>            <groupId>junit</groupId>            <artifactId>junit</artifactId>            <version>4.12</version>            <scope>test</scope>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-test</artifactId>            <version>4.3.8.RELEASE</version>        </dependency>        <!--spring相关包-->        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-web</artifactId>            <version>4.3.8.RELEASE</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-webmvc</artifactId>            <version>4.3.8.RELEASE</version>        </dependency>        <!--jstl-->        <dependency>            <groupId>javax.servlet</groupId>            <artifactId>jstl</artifactId>            <version>1.2</version>        </dependency>        <!--servlet-api-->        <dependency>            <groupId>javax.servlet</groupId>            <artifactId>javax.servlet-api</artifactId>            <version>3.1.0</version>        </dependency>    </dependencies>    <build>        <finalName>springmvc-learning</finalName>    </build></project>

2、由于使用java文件进行配置，所以可以将web.xml清空

web.xml

<?xml version="1.0" encoding="UTF-8"?><web-app xmlns="http://java.sun.com/xml/ns/javaee"         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee          http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"         version="3.0"></web-app>

3、在java目录下创建包，并创建一个RootConfig和WebConfig类

4、创建一个初始化配置的类SpittrWebAppInitializer，并继承AbstractAnnotationConfigDispatcherServletInitializer

package com.learn.config;import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;/** * 继承AbstractAnnotationConfigDispatcherServletInitializer的类会自动配置DispatcherServlet和spring应用上下文 * 1.在Servlet 3.0中，容器会在类路径中查找实现ServletContainerInitializer接口的类，并用它来配置Servlet容器 * 2.Spring中有ServletContainerInitializer接口的实现，名为SpringServletContainerInitializer，这个类又会查找实现WebApplicationInitializer的类并将配置任务交给它们来完成 * 3.AbstractAnnotationConfigDispatcherServletInitializer是WebApplicationInitializer的实现类，而我们的配置类SpittrWebAppInitializer又继承了它 * 4.因此可以使用我们的配置类来配置Servlet上下文 * spring in action */public class SpittrWebAppInitializer extends AbstractAnnotationConfigDispatcherServletInitializer{    protected Class<?>[] getRootConfigClasses() {        return new Class[]{RootConfig.class};    }    protected Class<?>[] getServletConfigClasses() {        return new Class[]{WebConfig.class};    }    protected String[] getServletMappings() {        //将DispatcherServlet映射到"/",相当于web.xml中配置的servlet-mapping        return new String[]{"/"};    }}

5、WebConfig类中配置视图解析器

package com.learn.config;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.ComponentScan;import org.springframework.context.annotation.Configuration;import org.springframework.web.servlet.ViewResolver;import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;import org.springframework.web.servlet.config.annotation.EnableWebMvc;import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;import org.springframework.web.servlet.view.InternalResourceViewResolver;@Configuration//将类作为配置配@EnableWebMvc//启用SpringMVC@ComponentScan("com.learn.controller")//启用组件扫描public class WebConfig extends WebMvcConfigurerAdapter{    //注册一个ViewResolver视图解析器bean,配置JSP视图解析器    @Bean    public ViewResolver viewResolver(){        InternalResourceViewResolver resolver=new InternalResourceViewResolver();        resolver.setPrefix("/WEB-INF/views/");        resolver.setSuffix(".jsp");        resolver.setExposeContextBeansAsAttributes(true);        return resolver;    }    //配置静态资源的处理，要求DispathServlet将对静态资源的请求转发到Servlet容器中默认的servlet    @Override    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer){        configurer.enable();    }}

6、RootConfig

package com.learn.config;import org.springframework.context.annotation.ComponentScan;import org.springframework.context.annotation.ComponentScan.Filter;import org.springframework.context.annotation.Configuration;import org.springframework.context.annotation.FilterType;import org.springframework.web.servlet.config.annotation.EnableWebMvc;@Configuration@ComponentScan(basePackages = "com.learn",excludeFilters = {        @Filter(type=FilterType.ANNOTATION,value= EnableWebMvc.class)})public class RootConfig {}

7、现在springmvc项目所需要的基本配置已经配置完毕，接下来创建一个HelloController

package com.learn.controller;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;@Controller//将此类作为控制器public class HelloController {    @RequestMapping(value="/hello")//设置请求映射，处理对"/hello"的请求    public String hello(){        return "hello";//视图名为hello，视图解析器会寻找WEB-INF/views/hello.jsp    }}

8、在WEB-INF/下建一个views文件夹，并在views目录下建一个hello.jsp

<html><body><h2>hello spring mvc</h2></body></html>

9、启动Tomcat

输入http://localhost:8080/hello进行测试

注：在配置Tomcat时，ApplicationContext设为了/,因此可以直接通过http://localhost:8080/访问项目，而不需要带上项目名称

10、使用mock进行单元测试

package com.learn.controller;import org.junit.Test;import org.springframework.test.web.servlet.MockMvc;import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;import org.springframework.test.web.servlet.result.MockMvcResultMatchers;import org.springframework.test.web.servlet.setup.MockMvcBuilders;import org.springframework.web.servlet.view.InternalResourceView;public class HelloControllerTest {    @Test    public void helloTest() throws Exception{        HelloController controller=new HelloController();        MockMvc mockMvc= MockMvcBuilders.standaloneSetup(controller).setSingleView(new InternalResourceView("/WEB-INF/views/hello.jsp")).build();        mockMvc.perform(MockMvcRequestBuilders.get("/hello")).andExpect(MockMvcResultMatchers.view().name("hello"));    }}

参考：Spring in Action