Spring MVC4 纯注解配置教程

阅读本文需要又一定的sping基础，最起码要成功的运行过一个SpringMvc项目。

在传统的Spring项目中，我们要写一堆的XML文件。而这些XML文件格式要求又很严格，很不便于开发。而网上所谓的0配置，并不是纯粹的0配置，还是要写一些xml配置，只是用了几个@Service，@Controller注解而已。

在这里，我讲介绍一种新的配置方式，一行XML代码都不需要，什么web.xml,Application-context.xml，Beans.xml，统统去死吧！

 

首先建立一个Maven项目，Packageing方式为war，项目结构为标准Maven WebApp结构。

pom文件如下（很多依赖都没用，懒得去掉了）：

<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.csonezp</groupId>    <artifactId>springdemo</artifactId>    <packaging>war</packaging>    <version>1.0-SNAPSHOT</version>    <name>dataplatform Maven Webapp</name>    <url>http://maven.apache.org</url>    <properties>        <spring.version>4.0.1.RELEASE</spring.version>    </properties>    <dependencies>        <dependency>            <groupId>junit</groupId>            <artifactId>junit</artifactId>            <version>4.11</version>        </dependency>        <!-- Spring dependencies -->        <dependency>            <groupId>asm</groupId>            <artifactId>asm-commons</artifactId>            <version>2.2.3</version>        </dependency>        <dependency>            <groupId>asm</groupId>            <artifactId>asm</artifactId>            <version>2.2.3</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-core</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-web</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-orm</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-jdbc</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-context</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-aop</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-expression</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-test</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-tx</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-webmvc</artifactId>            <version>${spring.version}</version>        </dependency>        <dependency>            <groupId>cglib</groupId>            <artifactId>cglib</artifactId>            <version>2.2.2</version>        </dependency>        <!-- Servlet API, JSTL -->        <dependency>            <groupId>javax.servlet</groupId>            <artifactId>javax.servlet-api</artifactId>            <version>3.0.1</version>            <scope>provided</scope>        </dependency>        <dependency>            <groupId>jstl</groupId>            <artifactId>jstl</artifactId>            <version>1.2</version>        </dependency>        <dependency>            <groupId>org.codehaus.jackson</groupId>            <artifactId>jackson-core-asl</artifactId>            <version>1.8.4</version>        </dependency>        <dependency>            <groupId>org.codehaus.jackson</groupId>            <artifactId>jackson-mapper-asl</artifactId>            <version>1.8.4</version>        </dependency>        <dependency>            <groupId>c3p0</groupId>            <artifactId>c3p0</artifactId>            <version>0.9.1.2</version>        </dependency>        <dependency>            <groupId>log4j</groupId>            <artifactId>log4j</artifactId>            <version>1.2.8</version>        </dependency>        <dependency>            <groupId>org.json</groupId>            <artifactId>json</artifactId>            <version>20090211</version>        </dependency>        <dependency>            <groupId>mysql</groupId>            <artifactId>mysql-connector-java</artifactId>            <version>5.1.6</version>        </dependency>        <dependency>            <groupId>spy</groupId>            <artifactId>spymemcached</artifactId>            <version>2.6</version>        </dependency>        <dependency>            <groupId>org.slf4j</groupId>            <artifactId>slf4j-api</artifactId>            <version>1.6.6</version>        </dependency>    </dependencies>    <build>        <finalName>dataplatform</finalName>    </build></project>

 

这个时候，就该进行Spring配置了。按传统方式来的话，首先要去web.xml写一堆配置，然后建立个管理beab的Beans.xml，管理spring mvc 的xml，再写一坨一坨Bean。就是先进一点的（也就是很多人说的0配置），也就是自己的业务Bean不用写进xml了，还是很麻烦。

而我这里讲的方式，则是完全不修改任何web.xml代码，不写一行XML代码的方式。

 

首先，在项目立建立一个Config.java文件：

** * Created by zhangpeng on 16-3-22. * 取代Beans.xml，纯注解配置各种BEAN */@Configuration@ComponentScan("com.csonezp")@EnableWebMvcpublic class Config {    /**     * jsp视图解析器的bean     * @return     */    @Bean    public UrlBasedViewResolver setupViewResolver() {        UrlBasedViewResolver resolver = new UrlBasedViewResolver();        resolver.setPrefix("/WEB-INF/");        resolver.setSuffix(".jsp");        resolver.setViewClass(JstlView.class);        return resolver;    }    /**     * 配置数据源     * @return     */    @Bean(name = "dataSource")    public ComboPooledDataSource getDataSource() {        try {            ComboPooledDataSource dataSource = new ComboPooledDataSource();            dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/mfdb");            dataSource.setDriverClass("com.mysql.jdbc.Driver");            dataSource.setUser("root");            dataSource.setPassword("zp1228");            dataSource.setMaxPoolSize(75);            return dataSource;        } catch (Exception e) {            return null;        }    }}

 

@Configuration注解就是告诉Spring这个是一个配置文件类，这里配置的Bean要交给Spring去管理。这个就是用来取代Beans.xml这种文件的。

@ComponentScan("com.csonezp")这个注解就是配置包扫描用的，不必多说了

@EnableWebMvc ，启用Spring MVC支持

 

这里面配置了两个Bean，第一个就是JSP的视图解析器，第二个则是配置了一个数据源。这些都可以对应到XML文件里面去的。找一个传统Spring项目，用xml文件对比着我这个类去看，会对这种配置方式有更深的了解。

 

下面要建立一个WebInitializer类继承WebApplicationInitializer，在这里添加一个servlet。这一步是用来取代在web.xml中添加servlet的步骤

import org.springframework.web.WebApplicationInitializer;import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;import org.springframework.web.servlet.DispatcherServlet;import javax.servlet.ServletContext;import javax.servlet.ServletException;import javax.servlet.ServletRegistration.Dynamic;public class WebInitializer implements WebApplicationInitializer {    public void onStartup(ServletContext servletContext) throws ServletException {                  AnnotationConfigWebApplicationContext ctx = new AnnotationConfigWebApplicationContext();        ctx.register(Config.class);          ctx.setServletContext(servletContext);                    Dynamic servlet = servletContext.addServlet("dispatcher", new DispatcherServlet(ctx));        servlet.addMapping("/");          servlet.setLoadOnStartup(1);                }  }

这样就OK啦！让我们写一些代码来测试一下吧！

import org.springframework.stereotype.Service;/** * Created by zhangpeng on 16-3-22. */@Servicepublic class HelloService {    public String getHello(String name) {        return name + ",Hello!";    }}

import com.guduo.dataplatform.service.HelloService;import com.guduo.dataplatform.service.MovieService;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Controller;import org.springframework.ui.ModelMap;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestParam;/** * Created by zhangpeng on 16-3-22. */@Controller@RequestMapping("/test")public class TestController {    @Autowired    HelloService helloService;    @Autowired    MovieService movieService;    @RequestMapping("/hello")    public String sayHello(@RequestParam("name") String name, ModelMap model) {        model.put("hello", helloService.getHello(name));        return "hello";    }}

一个service，一个controller。

启动项目，在浏览器中输入地址http://localhost:8080/dp/test/hello?name=sss

页面显示sss,Hello!

完工！

 

额，忘了演示Confgig里配置的bean如何使用了。其实和XML里的一样。这里拿一个DAO做演示吧，这里就注入了我们在config里配置的那个数据源

@Repositorypublic class MoviePlayIncDao {    private DataSource dataSource;    private JdbcTemplate jdbcTemplateObject;    @Autowired    public void setDataSource(DataSource dataSource) {        this.dataSource = dataSource;        this.jdbcTemplateObject = new JdbcTemplate(dataSource);    }    public List<MoviePlayIncreament> getMoviePlayInc(int movieId) {        try {            String SQL = "select * from movieplayincreament where movieid=?";            List<MoviePlayIncreament> list = jdbcTemplateObject.query(SQL, new MoviePlayIncMapper(), new Object[]{movieId});            return list;        } catch (Exception e) {            return null;        }    }}

转载：http://www.cnblogs.com/csonezp/p/5315725.html