What is difference between @controller and RestController?

@Controller is used to mark classes as Spring MVC Controller. @RestController annotation is a special controller used in RESTful Web services, and it's the combination of @Controller and @ResponseBody annotation. It is a specialized version of @Component annotation.

Can we use @controller instead of @RestController?

The @Controller is a common annotation which is used to mark a class as Spring MVC Controller while the @RestController is a special controller used in RESTFul web services and the equivalent of @Controller + @ResponseBody .

What is a RestController?

RestController is a Spring annotation that is used to build REST API in a declarative way. RestController annotation is applied to a class to mark it as a request handler, and Spring will do the building and provide the RESTful web service at runtime.

What is difference between RestController and RequestMapping?

In case of @RestController the parameter value depicts the component name or bean name, whereas in @RequestMapping the value parameter is used to specify the path. Both are used for different purpose. If you want to specify request URI path on controller class name use @RequestMapping annotation with @RestController .

What is the difference between @controller and @component?

@Component : It is a basic auto component scan annotation, it indicates annotated class is an auto scan component. @Controller : Annotated class indicates that it is a controller component, and mainly used at the presentation layer. @Service : It indicates annotated class is a Service component in the business layer.

@RestController Vs @Controller. Difference between @RestController and @Controller In Spring Boot

What is difference between @service and @repository?

@Service annotation is used with classes that provide some business functionalities. @Repository Annotation is used to indicate that the class provides the mechanism for storage, retrieval, update, delete and search operation on objects. @Service Annotation is a specialization of @Component Annotation.

What is difference between @bean and @component?

@Component is a class level annotation whereas @Bean is a method level annotation and name of the method serves as the bean name. @Component need not to be used with the @Configuration annotation where as @Bean annotation has to be used within the class which is annotated with @Configuration.

What is the difference between PostMapping and RequestMapping?

Both do the same job. The difference is that @PostMapping is part of a predefined group of compound annotations that internally use @RequestMapping . These annotations act as shortcuts that serve to simplify the mapping of HTTP methods and to more concisely express the methods of manipulation.

What is the difference between request mapping and GetMapping?

@RequestMapping is used at the class level while @GetMapping is used to connect the methods. This is also an important Spring MVC interview question to knowing how and when to use both RequestMapping and GetMapping is crucial for Java developers.

What is the difference between @service and @component in Spring?

@Component is a generic stereotype for any Spring-managed component. @Service annotates classes at the service layer. @Repository annotates classes at the persistence layer, which will act as a database repository.

What is the purpose of @ResponseBody?

The @ResponseBody annotation tells a controller that the object returned is automatically serialized into JSON and passed back into the HttpResponse object.

How do you write a RestController?

Is an API a controller?

Web API controller is a class which can be created under the Controllers folder or any other folder under your project's root folder. The name of a controller class must end with "Controller" and it must be derived from System. Web. Http.

What is difference between Spring and spring boot?

Key Differences

The key difference or key feature of Spring is dependency injection and for spring boot it's autoconfiguration, with the help of Spring Boot Framework developers can reduce development time, Developer Effort, and increase productivity.

What is the difference between Spring MVC and rest?

Spring MVC Framework and REST

Spring's annotation based MVC framework simplifies the process of creating RESTful web services. The key difference between a traditional Spring MVC controller and the RESTful web service controller is the way the HTTP response body is created.

Where @autowired can be used?

The @Autowired annotation provides more fine-grained control over where and how autowiring should be accomplished. The @Autowired annotation can be used to autowire bean on the setter method just like @Required annotation, constructor, a property or methods with arbitrary names and/or multiple arguments.

What is difference between @RequestParam and @PathVariable?

1) The @RequestParam is used to extract query parameters while @PathVariable is used to extract data right from the URI.

What is @PostMapping annotation in Spring boot?

@PostMapping is a composed annotation that acts as a shortcut for @RequestMapping(method = RequestMethod. POST) . @PostMapping annotated methods handle the HTTP POST requests matched with given URI expression.

Can we use RequestMapping in Spring boot?

@RequestMapping is the most common and widely used annotation in Spring MVC. It is used to map web requests onto specific handler classes and/or handler methods. @RequestMapping can be applied to the controller class as well as methods. name: Assign a name to this mapping.

What is GetMapping and post mapping?

From the naming convention we can see that each annotation is meant to handle respective incoming request method type, i.e. @GetMapping is used to handle GET type of request method, @PostMapping is used to handle POST type of request method, etc.

What is @GetMapping annotation in Spring boot?

The @GetMapping annotation is a specialized version of @RequestMapping annotation that acts as a shortcut for @RequestMapping(method = RequestMethod. GET) . The @GetMapping annotated methods in the @Controller annotated classes handle the HTTP GET requests matched with given URI expression.

What is @RequestBody in Spring boot?

The @RequestBody annotation allows us to retrieve the request's body. We can then return it as a String or deserialize it into a Plain Old Java Object (POJO). Spring has built-in mechanisms for deserializing JSON and XML objects into POJOs, which makes this task a lot easier as well.

What is difference between @bean and @autowired?

@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 difference between @component and @ComponentScan?

@Component and @ComponentScan are for different purposes. @Component indicates that a class might be a candidate for creating a bean. It's like putting a hand up. @ComponentScan is searching packages for Components.

What is difference between @configuration and @component?

@Configuration 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. @Component Indicates that an annotated class is a "component".