@Component is an annotation that allows Spring to automatically detect our custom beans. In other words, without having to write any explicit code, Spring will: Scan our application for classes annotated with @Component. Instantiate them and inject any specified dependencies into them. Inject them wherever needed.
Indeed, What is MVC in Spring?
The Spring Web MVC framework provides Model-View-Controller (MVC) architecture and ready components that can be used to develop flexible and loosely coupled web applications.
Then, What is the difference between @component and @bean? If we see component class like @Controller, @service, @repository will be scan automatically by the spring framework using the component scan. @Bean on the other hand can only be used to explicitly declare a single bean in a configuration class.
What is the difference between @service and @repository? @Service annotates classes at the service layer. @Repository annotates classes at the persistence layer, which will act as a database repository.
In the same way What is classpath scanning in Spring? A Classpath scanning basically means, detecting the classes that need to be managed by the Spring under a specified package. You need to make use of the spring @ComponentScan annotation with the @Configuration for classpath scanning.
What is ModelAndView in Spring?
ModelAndView is a holder for both Model and View in the web MVC framework. These two classes are distinct; ModelAndView merely holds both to make it possible for a controller to return both model and view in a single return value. The view is resolved by a ViewResolver object; the model is data stored in a Map .
What is hibernate in spring boot?
Hibernate is one of the popular implementations of JPA. Hibernate understands the mappings that we add between objects and tables. It ensures that data is stored/retrieved from the database based on the mappings. Hibernate also provides additional features on top of JPA.
What is AOP in Spring?
Advertisements. One of the key components of Spring Framework is the Aspect oriented programming (AOP) framework. Aspect-Oriented Programming entails breaking down program logic into distinct parts called so-called concerns.
What is IoC container in Spring?
Spring IoC Container is the core of Spring Framework. It creates the objects, configures and assembles their dependencies, manages their entire life cycle. The Container uses Dependency Injection(DI) to manage the components that make up the application.
What is Qualifier annotation in Spring?
The @Qualifier annotation in Spring is used to differentiate a bean among the same type of bean objects. If we have more than one bean of the same type and want to wire only one of them then use the @Qualifier annotation along with @Autowired to specify which exact bean will be wired.
What is the difference between @autowired and bean?
@Bean is just for the metadata definition to create the bean(equivalent to tag). @Autowired is to inject the dependancy into a bean(equivalent to ref XML tag/attribute).
What is DAO in Spring boot?
The Data Access Object (DAO) support in Spring is aimed at making it easy to work with data access technologies like JDBC, Hibernate, JPA or JDO in a consistent way.
What is a controller in Spring?
The @Controller annotation indicates that a particular class serves the role of a controller. Spring Controller annotation is typically used in combination with annotated handler methods based on the @RequestMapping annotation. It can be applied to classes only. It’s used to mark a class as a web request handler.
What is @repository in Spring boot?
@Repository Annotation is a specialization of @Component annotation which is used to indicate that the class provides the mechanism for storage, retrieval, update, delete and search operation on objects.
What is @EnableAutoConfiguration in Spring boot?
The @EnableAutoConfiguration annotation enables Spring Boot to auto-configure the application context. Therefore, it automatically creates and registers beans based on both the included jar files in the classpath and the beans defined by us.
What is @configuration in Spring boot?
@Configuration annotation indicates that a class declares one or more @Bean methods and may be processed by the Spring container to generate bean definitions and service requests for those beans at runtime. Since spring 2, we were writing our bean configurations to xml files.
What does @bean do in Spring boot?
Spring @Bean annotation tells that a method produces a bean to be managed by the Spring container. It is a method-level annotation. During Java configuration ( @Configuration ), the method is executed and its return value is registered as a bean within a BeanFactory .
What is the difference between model and ModelAndView?
Model is an interface while ModelMap is a class. ModelAndView is just a container for both a ModelMap and a view object. It allows a controller to return both as a single value.
What does the ViewResolver class?
ViewResolver is an interface to be implemented by objects that can resolve views by name. There are plenty of ways using which you can resolve view names. These ways are supported by various in-built implementations of this interface. Most commonly used implementation is InternalResourceViewResolver class.
What is bean in Spring?
In Spring, the objects that form the backbone of your application and that are managed by the Spring IoC container are called beans. A bean is an object that is instantiated, assembled, and otherwise managed by a Spring IoC container. Otherwise, a bean is simply one of many objects in your application.
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