spring装配注解(IOC容器加载控制)ComponentScan及ComponentScans使用

时间:2024-04-20 06:10:56

  ComponentScan,只写入value,可扫描路径下装配的@Contrller、@Service、@Repository

 @ComponentScan(value = "com.test")

测试类:

 @Test
@SuppressWarnings("resource")
public void test01() {
AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext(
MainConfig.class); String[] definitionNames = applicationContext.getBeanDefinitionNames();//获取spring装配的bean for (String name : definitionNames) {
System.out.println(name);
}
}

ComponentScan中还有参数excludeFilters、includeFilters、useDefaultFilters

ANNOTATION, // 按照注解 比如Controller Service
ASSIGNABLE_TYPE,// 按照给定的类型 比如某个类 like this

CUSTOM,//自定义验证

其中excludeFilters是设置屏蔽,excludeFilters可通过设置type进行过滤,classes进行详细的排除。其中使用方法如下:

 @ComponentScan(value = "com.test", excludeFilters =
{ @Filter(type = FilterType.ASSIGNABLE_TYPE ,
classes={BookService.class,Book.class}) })

通过注解类型屏蔽BookService及Book类

1 @ComponentScan(value = "com.test", excludeFilters =
2 { @Filter(type = FilterType.ASSIGNABLE_TYPE ,
3 classes={BookService.class,Book.class}) })

通过注解类型屏蔽service,controller

 @ComponentScan(value = "com.test", excludeFilters =
{ @Filter(type = FilterType.ANNOTATION ,
classes={Controller.class,Service.class}) })

而includeFilters是设置非屏蔽,只装配自己设定的类,要注意的是,在使用是要将useDefaultFilters关闭,默认时开启的。

只装配配置了service,controller的类

 @ComponentScan(value = "com.test", useDefaultFilters=false,includeFilters =
{ @Filter(type = FilterType.ANNOTATION ,
classes={Controller.class,Service.class}) })

ComponentScans的使用就更明了,里面放的是多个ComponentScan,直接放进去就可以直接使用

 @ComponentScans(
value={
@ComponentScan(value = "com.test", useDefaultFilters=false,includeFilters =
{ @Filter(type = FilterType.ANNOTATION ,
classes={Controller.class}) })
}
)

CUSTOM自定义验证,需要我们写一个类,去实现TypeFilter的方法,下面测试类,对className中包含了“ser”的允许装配进容器

 public class MyTypeFilter implements TypeFilter {

     public boolean match(MetadataReader metadataReader,
MetadataReaderFactory metadataReaderFactory) throws IOException {
// TODO Auto-generated method stub
// 获取当前类注解的信息
AnnotationMetadata annotationMetadata=metadataReader.getAnnotationMetadata();
//获取当前正在扫描的类信息
ClassMetadata classMetadata=metadataReader.getClassMetadata();
//获取当前类资源(类的路径)
Resource resource=metadataReader.getResource(); String className=classMetadata.getClassName(); System.out.println("--->"+className);
if(className.contains("ser")){
return true;
} return false;
} }
 @ComponentScans(value={@ComponentScan
(value = "com.test", useDefaultFilters=false,
includeFilters = {@Filter(type=FilterType.CUSTOM ,classes={MyTypeFilter.class})}
)}
)