SPRINGMVC annotation Configuration

Let's look at a few confusing configurations for simplifying development: <mvc:annotation-driven/>, <context:annotation-config/>, <context: Component-scan/>.

<mvc:annotation-driven/> will do several things:

1. Register the defaultannotationhandlermapping with the spring container.
2. Register the Annotationmethodhandleradapter with the spring container.
3. Configure some messageconverter.
4. Addresses the premise configuration for @Controller annotations that handlermapping can know who is handling the request.

<context:annotation-config/> will do several things:

1. Register the Autowiredannotationbeanpostprocessor with the spring container.
2. Register the Commonannotationbeanpostprocessor with the spring container.
3. Register the Persistenceannotationbeanpostprocessor with the spring container.
4. Register the Requiredannotationbeanpostprocessor with the spring container.
5. Before you use <context:annotationconfig/>, you must declare the context namespace <context:component-scan/> in the <beans> element. <context:component-scan/> Scans the package to implement the annotation driven Bean definition. That is, the bean that @Controller the class that is identified is registered in the container.

<context:component-scan/>Not only enables the ability to scan class packages to implement annotation-driven Bean definitions, but also enables annotation-driven auto-injection (that is, implicitly, internally registered Autowiredannotationbeanpostprocessor and Commonannotationbeanpostprocessor). So when using <context:component-scan/>, unless you need to use persistenceannotationbeanpostprocessor and Requiredannotationbeanpostprocessor two Processor functions (such as JPA, etc.), or you can remove <context:annotation-config/>

SPRINGMVC annotation Configuration