SSM异常：No qualifying bean of type `CompanyDao` available expected at least 1 bean which qualifies

1、边写代码边做测试，由于采用聚合架构及Maven的方式创建项目，一个父项目(Project)会有多个子模块(Module)，每个子模块都会在resources目录下创建spring文件夹，用于存放spring相应的配置文件，于是测试时遇到了以下的异常：

java.lang.IllegalStateException: Failed to load ApplicationContext
	at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:125)
	at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:107)
	at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:117)
	at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83)
	at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:242)
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'companyServiceimpl': Unsatisfied dependency expressed through field 'companyDao'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'CompanyDao' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {
     @org.springframework.beans.factory.annotation.Autowired(required=true)}
	at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:586)
	at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:91)
	at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:372)
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'CompanyDao' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {
     @org.springframework.beans.factory.annotation.Autowired(required=true)}
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1504)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1101)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1062)
	at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:583)
	... 42 more

2、主要的异常信息为：

(1) java.lang.IllegalStateException: Failed to load ApplicationContext. （没有加载到ApplicationContext相应的配置文件）
(2) UnsatisfiedDependencyException: Error creating bean with name ‘companyServiceimpl’: Unsatisfied dependency expressed through field ‘companyDao’;（错误创建bean，名称为：companyServiceImpl，无法依赖bean：companyDao）
(3) No qualifying bean of type ‘CompanyDao’ available: expected at least 1 bean which qualifies as autowire candidate.（没有找到符合类型的bean：CompanyDao）

3、由于SSM框架整合时，Spring需要依赖MyBatis对数据库进行操作，而ApplicationContext-service.xml文件已经加载到了，但是没有加载到ApplicationContext-dao.xml文件，于是会出现异常：No qualifying bean of type ‘CompanyDao’(没有找到符合类型的bean：CompanyDao)（测试时，下图中左边栏也出现类似的异常，却不知道异常出现在哪里，其实还是ApplicationContext-dao.xml文件没有被加载到）

4、将上图中的@ContextConfiguration注解扫描的范围扩大，于是就能扫描并加载到ApplicationContext-dao.xml文件

classpath  加载当前项目类路径下的配置文件
classpath* 加载所有项目(包含子模块)类路径下的配置文件
@ContextConfiguration("classpath*:spring/spring-*.xml")

5、于是成功加载到ApplicationContext-dao.xml配置文件后，运行代码，上述的异常已不存在