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") @EnableWebMvc public 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. */ @Service public 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
@Repository public 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; } } }
