Spring+SpringMVC+Mybatis基于去web.xml 、JavaConfig风格集成

SSM框架整合的案例较多、但是在去除WEB.XML形式的还是不是很多、偶然看到还有通过

实现 WebApplicationInitializer  接口来实现动态注册Servlet  就觉得比较有意思 值得试试看；

首先万变不离其宗POM 依赖如下；

	4.0.0
	com.javen.maven02
	maven02
	war
	0.0.1-SNAPSHOT


	
		
		4.3.2.RELEASE
		
		3.2.6
		
		1.7.7
		1.2.17
	

	
		
			junit
			junit
			4.11
			
			test
		
		
			javax.servlet
			javax.servlet-api
			3.1.0
		

		
		
			org.springframework
			spring-core
			${spring.version}
		
		
			org.jsoup
			jsoup
			1.9.2
		

		
			org.springframework
			spring-web
			${spring.version}
		
		
			org.springframework
			spring-oxm
			${spring.version}
		
		
			org.springframework
			spring-tx
			${spring.version}
		

		
			org.springframework
			spring-jdbc
			${spring.version}
		
	
		
			com.alibaba
			druid
			1.1.9
				
			org.springframework
			spring-webmvc
			${spring.version}
		
		
			org.springframework
			spring-aop
			${spring.version}
		

		
			org.springframework
			spring-context-support
			${spring.version}
		

		
			org.springframework
			spring-test
			${spring.version}
		
		
		
			org.mybatis
			mybatis
			${mybatis.version}
		
		
		
			org.mybatis
			mybatis-spring
			1.2.2
		

		
		
			javax
			javaee-api
			7.0
		

		
		
			mysql
			mysql-connector-java
			5.1.36
		
		
		
			commons-dbcp
			commons-dbcp
			1.2.2
		

		
		
			jstl
			jstl
			1.2
		
		
		
		
			log4j
			log4j
			${log4j.version}
		


		
		
			com.alibaba
			fastjson
			1.1.41
		


		
			org.slf4j
			slf4j-api
			${slf4j.version}
		

		
			org.slf4j
			slf4j-log4j12
			${slf4j.version}
		
		
		
		
			org.codehaus.jackson
			jackson-mapper-asl
			1.9.4
		

		
		
			commons-fileupload
			commons-fileupload
			1.3.1
		
		
			commons-io
			commons-io
			2.4
		
		
			commons-codec
			commons-codec
			1.9
		
		
		
			com.fasterxml.jackson.core
			jackson-databind
			2.7.4
		
		
			com.fasterxml.jackson.core
			jackson-core
			2.7.4
		
		
			com.fasterxml.jackson.core
			jackson-annotations
			2.7.4
		
		
		

		
			com.github.penggle
			kaptcha
			2.3.2
		

		
		
			javax.mail
			mail
			1.4.5
		

		

		
			io.springfox
			springfox-swagger2
			2.8.0
		
		
			io.springfox
			springfox-swagger-ui
			2.8.0
		


		
		
			org.springframework.data
			spring-data-redis
			1.7.2.RELEASE
		
		
			redis.clients
			jedis
			2.8.1
		
		
			org.apache.jmeter
			ApacheJMeter_java
			3.3
		

	
	
		SpringMVCmybatis

		

			

				org.apache.maven.plugins

				maven-compiler-plugin

				3.3

				

					

					1.8

					1.8

				

			

		

	

你需要有一个这样的工程目录结构  java 是源码  resources主要存储一些配置文件 webapp 主要存放页面文件和前台文件；

第一步：首先实现动态注册首先要实现WebApplicationInitializer 或者继承

AbstractAnnotationConfigDispatcherServletInitializer类

package com.javen.Config;

import org.apache.log4j.Logger;
import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;


/**
 * 
 * servlet3.0以上支持
 * @author Administrator
 *
 */
public class WebAppInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {

	private final static Logger LOG = Logger.getLogger(WebAppInitializer.class);
	
	@Override
	protected Class[] getRootConfigClasses() {
		LOG.info("------root配置类初始化------");
		return new Class[] { RootConfig.class };
	}

	@Override
	protected Class[] getServletConfigClasses() {
		LOG.info("------web配置类初始化------");
		return new Class[] { WebConfig.class };
	}

	@Override
	protected String[] getServletMappings() {
		LOG.info("------映射根路径初始化------");
		return new String[]{ "/" };//请求路径映射，根路径
	}
	
}

第二步：编写JavaConfig风格的配置文件类；

RootConfig.class 指的是Spring的默认配置文件类也就是之前的applicationContex.xml

有一些需要优先初始化的类 可以在这个类中写

@Configuration
@ComponentScan(basePackages="com.javen.*")

public class RootConfig {
	
	@Bean
	public static PropertyPlaceholderConfigurer properties() {
		final PropertyPlaceholderConfigurer ppc = new PropertyPlaceholderConfigurer();
		ppc.setIgnoreResourceNotFound(true);
		final List resourceLst = new ArrayList();
		resourceLst.add(new ClassPathResource("jdbc.properties"));
		resourceLst.add(new ClassPathResource("mail.properties"));
		resourceLst.add(new ClassPathResource("redis.properties"));
		ppc.setLocations(resourceLst.toArray(new Resource[] {}));
		return ppc;

	}

WebConfig.class 需要继承WebMvcConfigurerAdapter 指的是Spring mvc  的配置文件类

@Configuration
@EnableWebMvc
@EnableSwagger2
@ComponentScan( "com.javen.controller" )
public class WebConfig  extends WebMvcConfigurerAdapter{

      @Bean
      public ViewResolver viewResolver(){
           InternalResourceViewResolver resolver = new InternalResourceViewResolver();
           resolver.setPrefix("/WEB-INF/page/");
           resolver.setSuffix(".html");
           return resolver;
       }
      
      @Bean(name="multipartResolver")
      protected CommonsMultipartResolver MultipartResolver() {
         CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver();
         //multipartResolver.setUploadTempDir(new FileSystemResource("/tmp"));//可以不设置
         multipartResolver.setMaxUploadSize(2097152);//2M
         multipartResolver.setMaxInMemorySize(0);
         multipartResolver.setDefaultEncoding("UTF-8");
         return multipartResolver;
      }
      
      
        public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
              configurer.enable();
         }
        
        public void addInterceptors(InterceptorRegistry registry) {  
              registry.addInterceptor(new TokenInterceptor()).addPathPatterns("/**");  
              registry.addInterceptor(new Mvcinterceptor()).addPathPatterns("/**");  
          }  
}

原理解析：

@HandlesTypes(WebApplicationInitializer.class)
public class SpringServletContainerInitializer implements ServletContainerInitializer {]

ServletContainerInitializer  这个类是Servlet提供的接口

@HandlesTypes(WebApplicationInitializer.class)是一个注解说引入这个接口

运行步骤 

1、tomcat启动后会去找实现ServletContainerInitializer接口

2、这时候他找到 SpringServletContainerInitializer 但是发现实现类需要扫描

@HandlesTypes(WebApplicationInitializer.class)然后将扫描结果返回给SpringServletContainerInitializer 

3、我们的入口类实现WebApplicationInitializer所以自然会被找到并动态注册；

详细的源码可以转至：https://github.com/379753498/SpringMVCmybatis