一篇文章带你掌握主流服务层框架——SpringMVC( 三 ) _生活百科

Spring加载的bean设定范围为精准范围，例如service包，dao包等

package com.itheima.config;import org.springframework.context.annotation.ComponentScan;import org.springframework.context.annotation.Configuration;import org.springframework.context.annotation.FilterType;import org.springframework.stereotype.Controller;@Configuration@ComponentScan({"com.itheima.service","com.itheima.dao"})public class SpringConfig {}

Servlet容器简化写法我们的Servlet容器中可以定义Spring和SpringMVC的配置文件

package com.itheima.config;import org.springframework.web.context.WebApplicationContext;import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;import org.springframework.web.servlet.support.AbstractDispatcherServletInitializer;public class ServletContainersInitConfig extends AbstractDispatcherServletInitializer {// 配置SpringMVC配置文件protected WebApplicationContext createServletApplicationContext() {AnnotationConfigWebApplicationContext ctx = new AnnotationConfigWebApplicationContext();ctx.register(SpringMvcConfig.class);return ctx;}// 配置Spring配置文件protected WebApplicationContext createRootApplicationContext() {AnnotationConfigWebApplicationContext ctx = new AnnotationConfigWebApplicationContext();ctx.register(SpringConfig.class);return ctx;}// 配置拦截路径protected String[] getServletMappings() {return new String[]{"/"};}}

我们可以注意到：
Spring和SpringMVC导入方法中均采用AnnotationConfigWebApplicationContext来创建对象
两者之间的区别仅仅是class包的不同

Spring给了我们一种新的继承类用于简化开发：

package com.itheima.config;import org.springframework.web.context.WebApplicationContext;import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;import org.springframework.web.servlet.support.AbstractDispatcherServletInitializer;//web配置类简化开发，仅设置配置类类名即可public class ServletContainersInitConfig extends AbstractAnnotationConfigDispatcherServletInitializer {protected Class<?>[] getRootConfigClasses() {return new Class[]{SpringConfig.class};}protected Class<?>[] getServletConfigClasses() {return new Class[]{SpringMvcConfig.class};}protected String[] getServletMappings() {return new String[]{"/"};}}