50+ [REAL-TIME] Spring MVC Interview Questions and Answers

Last updated on 15th May 2024, Popular Course

Spring MVC is a widely-used framework for building web applications in Java. It follows the Model-View-Controller architectural pattern, providing developers with a structured approach to develop scalable and maintainable web applications. With features like robust request handling, flexible configuration, and seamless integration with other Spring modules, Spring MVC simplifies the development process while promoting best practices. It’s favored for its extensibility, testability, and comprehensive documentation, making it a popular choice among developers for creating modern, enterprise-grade web applications.

1. What is MVC?

Ans:

The Model-View-Controller (MVC) pattern is an architectural design pattern for software that divides an application’s functionality into three interconnected parts: model, View, and Controller. This approach makes it easier to reuse code and develop applications in parallel, and it is a widely used development approach. 

2. What is Spring MVC?

Ans:

Spring MVC is a Java framework for developing dynamic web applications. It implements all the basic features of a core spring framework, such as Dependency Injection and Inversion of Control. It adheres to the Model-View-Controller design pattern and architecture-specific format. Thus, view technologies such as JSP+JSTL, Apache Velocity, Thyme Leaf, and Free Marker can be used to generate a view page.

3. What is Spring MVC’s Front Controller?

Ans:

• The org. Spring framework. Web. The servlet package contains the Dispatcher Servlet class, the Front Controller. 
• It controls the application flow and forwards the request to the relevant Controller. 
• The web.xml file must contain the Dispatcher Servlet class specification.

4. Could you describe the Spring MVC flow?

Ans:

• The Dispatcher Servlet, which functions as the front Controller, intercepts the request once it has been produced.
•  The request is sent to the Controller by the Dispatcher Servlet, which receives an entry of the handler mapping from the XML file.
• The Controller gives back an item of View And Model.
• The Coordinator The servlet invokes the designated view component once it has verified the view resolver item in the XML file.

5. What benefits does the Spring MVC Framework offer?

Ans:

The benefits of the Spring MVC Framework are as follows: –

• Different roles: The application is divided into three interconnected levels by Spring MVC, each with a specific role.
•  Lightweight: Use a lightweight servlet container to design and launch your application.
• Robust Configuration: It offers strong Configuration for application classes and the framework, facilitating simple cross-context referencing between web controllers, business objects, and validators.
• Quick development: Spring MVC makes working quickly and in parallel easier.
• Reusable business code: This permits the creation of new objects without using the current business objects.
•  Flexible Mapping: This feature offers precise annotations that make it simple to reroute the page.

6. What is contained in an additional configuration file of a Spring MVC application?

Ans:

The properties data are in an extra configuration file with the Spring MVC application. This file may be generated as a properties file or as an XML file. Generally speaking, we define the base package and view resolver in this file, which is where DispatcherServlet looks for the path of the view components and controller classes. It may also include several additional configuration attributes.

7. In Spring MVC, what is an Internal Resource View Resolver?

Ans:

In Spring MVC, an internal view is resolved using a class called Internal Resource View Resolver. In this instance, you can specify the attributes such as prefix and suffix, where the view page’s location is contained in the prefix and its extension is contained in the suffix. As an illustration:- 

1..<\property name=”suffix” value=”.jsp”> 

8. How does one declare a class in Spring MVC as a controller class?

Ans:

Use the Controller annotation to designate a class as a controller class. This annotation must be specified on the class name. 

As an illustration:

• Controller 
• Class Demo 
• ~{ 
• ~ 
• ~}

9. How may the controller class’s methods be mapped to a URL?

Ans:

The controller class and its functions are mapped using the RequestMapping annotation. This annotation can be specified with a specific method name or class name. URL that corresponds to the requested page’s route. As an illustration:- 

1. Controller

2. “/form” RequestMapping

3. Lecture Demo

RequestMapping(“/show”) 4.~5.

6. public String display()

7. * 8. * 9. * 10. * 11. *

10. Explain the differences between Spring Boots and Spring.

Ans:

Aspect	Spring	Spring Boot
Purpose	Comprehensive framework for Java development	Simplifies creation of stand-alone, production-grade Spring-based applications
Configuration	Requires manual configuration	Emphasizes convention over configuration, offers auto-configuration and sensible defaults
Dependency Management	Manual dependency management	Simplifies dependency management with starter dependencies and auto-configuration
Embedded Servers	Needs external servlet containers (e.g., Tomcat, Jetty)	Comes with embedded servlet containers for standalone deployment

11. In Spring MVC, what does the PathVariable annotation mean?

Ans:

The URI template’s value is extracted using the PathVariable annotation. It is transmitted within the handler method’s constraints.

As an illustration:

• :RequestMapping(“/show/{id}”)  
• Public String handler (Model map, String s, PathVariable(“id”))
• { 
• }

12. What function does the ResponseBody annotation serve?

Ans:

The returned object is automatically serialized in JSON and bound to the HTTP response body using the ResponseBody annotation. In this case, using the model is not necessary.

As an illustration:- 

• “/show” => RequestMapping
• ResponseBody
• the ResponseHandler display for the public  
• the RequestBody ShowForm form) 
• ~ return new ResponseHandler(“display form”); 
• ~ }
• ~}

13. How does Spring MVC use the Model interface?

Ans:

The Model interface functions as a container for the application’s data.  Any type of data, including objects, texts, database information, etc., can be used in this context. The model in Spring MVC operates as a container holding the application’s data. The Model interface must be located in the application’s controller section.

14. In Spring MVC, what do you mean by ModelAndView?

Ans:

A class called ModelAndView contains both the Model and the View, where the View is a representation of the data, and the model is a representation of the data. This class returns the class returns the return value. Public class org.springframework.web.servlet. ModelAndView In the web MVC framework, ModelAndView extends Object—holder for both Model and View. Keep in mind that these are different. This class enables a controller to return the model and the View in a single return value.

15. In Spring MVC, what is ModelMap?

Ans:

• HttpServletRequest interface: The javax.servlet.The HTTP package contains the HttpServletRequest interface. In Spring, HttpServletRequest allows you to read user-provided HTML form data, just like Servlets.
• RequestParam annotation: This annotation automatically links the form data to the parameter using the supplied method by reading the form data.
• ModelAttribute annotation links a named model attribute to a method parameter or its return value.

16. What is the purpose of ResponseBody?

Ans:

A controller is informed that the object returned is automatically serialized into JSON via the ResponseBody annotation and then returned to the HttpResponse object. When you use the ResponseBody annotation on a method, Spring automatically translates the return value and writes it to the HTTP response.

17. What is the form tag library for Spring MVC?

Ans:

The form tags in Spring MVC are similar to data binding-aware tags in that they can automatically set and get data from Java objects and beans. These tags are a web page’s reusable and configurable building components. Spring MVC offers view technologies, which make it simple to create, access, and manage data.

18. What do you mean by Spring MVC validations?

Ans:

One of the most significant components of Spring MVC is the validation, which limits the user’s input. The Bean Validation API and Spring 4 or later versions must be used to confirm the user’s input. Applications that are client-side or server-side can both be validated by Spring validations. We can quickly validate user input data using the Spring MVC framework’s standard predefined validators. The widely used method for data validations in Spring applications is the Bean Validation API.

19. What is an API for Bean Validation?

Ans:

• A Java specification called the Bean Validation API limits object models using annotations. Here, we can validate a length, number, regular expression, etc., and offer personalized confirmations.
• Bean Validation API needs to be implemented because it is merely a specification. Therefore, the Hibernate Validator is used for that. The Hibernate Validator is an entirely compliant JSR-303/309 implementation that enables the expression and validation of application constraints.

20. Why is valid annotation used?

Ans:

We use the RequestBody annotation to indicate that the request body ought to be associated with the user parameter. The user object’s validation is started by using the Valid annotation. This instructs Spring to apply the validation criteria specified in the User class to the request body.

21. In Spring MVC validations, what does BindingResult serve as?

Ans:

An interface that holds validation data is called BindingResult. As an illustration:”/hello again”) 

• RequestMapping 
• public String submitForm (Valid ModelAttribute(“emp”)) Worker e, Binding Outcome br)
• ~ 
• ~ if(br.hasErrors())
• { return “view page”; } ^ }
• Otherwise
• ~
• ~ return “final”;
• return “final”; 
• return “final”

22. how can I verify that the user entered a number within a range in Spring MVC?

Ans:

Using the following annotations in Spring MVC Validation, we may verify that the user’s input falls within a given range of numbers: o Min annotation—That’s 

o Min annotation: When using the Min annotation, an integer value must be supplied. The user’s input must meet or exceed this value.

o Max annotation: An integer value must be given with the Max annotation. The user input must meet this value or less.

23. how can I verify user input in a specific order in Spring MVC?

Ans:

The Spring MVC Validation enables us to validate user input in a certain order by using the pattern annotation.  Here, we may pass the annotation with the necessary regular expression to the regex attribute.

24. How does Spring MVC work?

Ans:

The steps outlined below are how Spring MVC handles user requests: The primary controller action controller uses the URL to determine which Controller to forward the request to.

• Data Processing: Request is handled by the Controller
• Model Preparation: The Controller prepares to present the data model to the user.
• View Selection: The system selects a view template to display the model data.
• Rendering: Model data is loaded into the view template.
• User Response: The user receives a copy of the created webpage. 

25. What are the Spring MVC Framework’s primary benefits?

Ans:

The primary benefits of the Spring MVC Framework are as follows:-

• Modular Architecture: By encouraging a modular design that divides concerns (Model, View, Controller), Spring MVC facilitates the development, testing, and maintenance of applications.
• Flexibility: A variety of view technologies are supported, enabling developers to select the most appropriate one .respective project, like FreeMarker, JSP, or Thymeleaf
• Reusable Components: The framework promotes the development of reusable components, which results in effective application development and maintenance.
• Customizable: The framework’s features, such as view resolvers and URL mappings, can be altered by developers.
• Scalability: Applications can extend vertically and horizontally because of Spring’s modular design and support for multiple application servers. 

26. What fundamental issue does the Spring MVC framework resolve?

Ans:

By offering a structured architecture that divides concerns (Model, View, Controller) and streamlines the development process, the Spring MVC framework effectively addresses the fundamental issue of the efficient and structured creation of online applications. Prior to Spring MVC, web application developers frequently struggled to handle the intricacy of interactions between many components, making apps challenging to scale, test, and manage.

27. Describe the main characteristics of the Spring Framework.

Ans:

Spring MVC’s main characteristics are: 

• It offers good handler mapping, binding, view resolution, and validation customization.
• Spring MVC allows defining an infinite controller method, significantly increasing the application’s adaptability and flexibility.
• It can set up the classes and framework as beans efficiently.
• It separates the responsibilities and functional roles.
• Using a map facilitates the model’s transfer. In addition to supporting velocity, JSTL, and JSP, the user can choose theme resolution and locale.
• Spring supports data binding, themes, and Bean lying cycles up to HTTP requests and has its tag library.

28. which increases its flexibility. What is the form tag library for Spring MVC? 

Ans:

The Spring Framework offers a collection of unique tags called the Spring MVC form tag library, which makes managing and generating HTML forms for online applications easier. These tags are made to integrate easily with Spring’s MVC architecture and help with server-side form data binding to model objects. This tag library is beneficial for activities like rendering form elements, filling them with data from model objects, and managing form submissions.

29. Compared to other MVC frameworks, what are the advantages of the Spring MVC framework?

Ans:

The following is a list of advantages the Spring MVC framework has over other MVC frameworks:

• Every role in Spring MVC has a dedicated object. As a result, it clearly defines the roles.
• Within Spring MVC, you can expand a particular framework base class by using your code as commands rather than mirroring it.
• Spring MVC offers easy-to-use and robust configuration options for JavaBeans application classes and the framework.
• Adaptable binding, validation, view resolution, and handler mapping.
• Locale and theme resolution customization.

30. What does the Spring MVC framework’s DispatcherServlet do?

Ans:

The DispatcherServlet implements the Front Controller design pattern, which manages all incoming web requests for a Spring MVC application. The Front Controller paradigm is a popular pattern in online applications. It takes in all requests and forwards them to other application components for processing. Web requests are routed to the Spring MVC controllers using the  DispatcherServlet in Spring MVC. 

31. Describe Spring MVC’s Front Controller.

Ans:

The Front Controller is a class called DispatcherServlet. It is in charge of overseeing the application’s flow and forwarding the request to the relevant Controller. Front Controller: The DispatcherServlet class is the Front Controller in Spring Web MVC. It is in charge of overseeing the Spring MVC application’s flow.

32. Does an application context facilitate the DispatcherServlet’s instantiation?

Ans:

• An application context is not used to instantiate the DispatcherServlet. Instead, it is instantiated by Servlet containers such as Tomcat or Jetty. 
• To use the DispatcherServlet, define it in the web.xml file. 
• Instead of building its internal web application context, DispatcherServlet may be injected with one. 
• This is helpful in environments supporting Servlet 3.0+, which allows programmatic servlet registration. 
• Examples. For further information, see the Javadoc for DispatcherServlet(WebApplicationContext).

33. What is the Spring MVC root application context?

Ans:

The context loaded via ContextLoaderListener is the root application context in Spring MVC. Globally available resources should be part of this context, whereas servlet-specific resources are initialized using the DispatcherServlet. Multiple DispatcherServlet instances are permitted in a Spring MVC web application. Thus, a root context may belong to several contexts, each unique to a particular servlet.

34. What does Spring MVC’s ContextLoaderListener do?

Ans:

• In Spring MVC, the ContextLoaderListener loads, constructs, and inserts the ApplicationContext into the ServletContext. 
• It also connects the ApplicationContext’s lifecycle to the ServletContext’s lifecycle.  
• The getServletContext() function can be used to obtain ServletContext from WebApplicationContext.

35. What is the purpose of the Controller annotation?

Ans:

Using the Controller annotation, a class can be designated as acting as a controller. Its primary function is to serve as a stereotype by outlining the role of the annotated class. Using the annotation Controller, we can declare a particular class as a controller in the Spring framework. Keep in mind that Java annotations are similar to code metadata. They provide context to your code, which aids the framework in doing its job.

36. In Spring MVC, how do you declare a class as a controller class?

Ans:

To declare a class as a controller in Spring MVC, you must include the Controller annotation on the class name, as demonstrated below. Manager class ClassName{} using the Controller and RequestMapping annotations. This class is identified as Controller by the Controller annotation. The supplied URL name is mapped to the class using the Requestmapping annotation.

37. How can a controller be made without the need for an annotation?

Ans:

• In Spring MVC, the Controller is defined using the Controller annotation. 
• However, by adding the Component annotation to the Controller classes, we can easily create a controller without utilizing the Controller annotation. 
• The ResponseBody is unnecessary because the Controller is marked with the RestController annotation. 
• The controller class’s request processing methods automatically deserialize return objects into HttpResponse.

38. How would you associate a URL with a controller class and its method?

Ans:

The RequestMapping function maps a controller class and its methods to a URL. Annotation is applied. This annotation must be supplied with the specified URL (path of the requested page) on the class and method names. As an illustration, the Controller RequestMapping(“/path1”) class RequestMapping(“/path2”) Class_Name{ public string Method_Name(){} }

39. List some acceptable return kinds for a controller method.

Ans:

Some common valid return types for a controller method are as follows:

• absent
• Cord
• Examine
• Chart
• Interface Model
• ViewAndModel (Class)
• Headers for HTTP
• ResponseEntity or HttpEntity

Every return type has a distinct function. For example, if you wish to return void instead of any view name, you should declare the void return type. Make a String the return type to provide the view name.

40. What Does Spring MVC’s Model Mean?

Ans:

The Model in Spring MVC serves as a reference for the data needed for rendering. It functions as a container for the application’s data, which may be in any format, including objects, strings, database information, etc. The model is always built and provided for viewing in Spring MVC.

41. In Spring MVC, what does a view mean?

Ans:

In a Spring MVC application, a view is an interface whose implementations expose the model and rendering context. It is employed to provide data to the user in a specific format. In Spring MVC, a view resolver resolves a view, and a view name addresses a view.

42. In Spring MVC, what is a ViewResolver?

Ans:

• ViewResolver makes working with views in Spring MVC possible. 
• It makes it possible to render models in the browser without attempting to use a particular view technology. 
• It offers a mapping of view names to their corresponding views.

43. What pattern does the View Resolver follow?

Ans:

A J2EE paradigm called View Resolver enables a web application to dynamically select its view technology, such as JSF, XSLT, Tapestry, HTML, and JSP. In this case, the Controller returns the view name, and the View resolver stores a mapping of various views. The View Resolver then receives the mapping to choose a suitable view.

44. How can the Spring MVC controller obtain HTML form data?

Ans:

Using Spring MVC, you can use the RequestParam annotation to obtain HTML form data that a user has submitted to the Controller. Let’s examine a simple illustration.

html> \title>HTML Form

Name: This form has a single Name field, a submit button, and other features.

Import org. Spring framework.web.bind.annotation.PostMapping;

import org. Spring framework.web.bind.annotation.RequestParam; 

Controller public class 

import org. Spring framework. Stereotype.Controller; 

PostMapping(“/processors”) in MyController

processor(RequestParam(“name”), public String name) 

{ System. Out.println(“Name: ” + name); 

45. Which ViewResolver types are available in Spring MVC?

Ans:

The various ViewResolvers are as follows:

• ViewResolver Abstract Catching
• XMLViewResolver
• BundleViewResolver for Resources
• ViewResolver with URL
• ViewResolver for Internal Resources
• FreeMakerViewResolver 

46. In the rendering stage, how is the appropriate View selected?

Ans:

The DispatcherServlet checks with the ViewResolver to determine the correct View after receiving logical view names from the Controller. Depending on how the ViewResolver is implemented, the logical View is resolved into a physical resource, such as a JSP page.

47. Why ought I utilize a ViewModel?

Ans:

The following are some advantages of applying the MVVM pattern: It may be difficult or dangerous to modify an old model implementation if it encapsulates the current business logic. Here, the view model serves as an adapter for the model classes, keeping you from modifying the model code in a significant way.

48. What kinds of annotations are utilized to handle which types of incoming HTTP request methods?

Ans:

The annotations used are as follows: 

• GetMapping
• PostMapping
• Putting Maps
• DeleteMapping. 

49. What does Spring MVC’s RequestParam Annotation serve as?

Ans:

To extract and map the query parameter to the method parameter in your Controller, utilize Spring MVC’s RequestParam Annotation. It retrieves the parameter’s value from the form request. The RequestParam annotation in Spring MVC automatically links the form data to the parameter in the supplied method. Thus, it disregards the HttpServletRequest object’s need to read the provided data.

50. What does Spring MVC’s PathVariable Annotation serve to accomplish?

Ans:

Annotation PathVariable In Spring MVC, the values of The URI template variables are extracted using the PathVariable annotation, and their values are set using the method parameter. To get data from the URL path, use the PathVariable annotation. You can tie placeholders defined in the request mapping URL to method parameters annotated with PathVariable. This enables you to use dynamic values from the URL in your code.

51. What is the Spring MVC ResponseBody annotation used for?

Ans:

In Spring MVC, the ResponseBody annotation informs the Controller that the returned object is serialized and immediately returned to the HttpResponse object. The HTTP request body data, frequently in XML or JSON format, is extracted using RequestBody, deserializing it into a Java object. To extract specific parameter values from the request URL or submitted form data, use RequestParam.

52. how can we read data from the form differently in Spring MVC?

Ans:

The methods listed below allow us to read data from the form:

• The form data is read using the RequestParam annotation, which ties it to the Controller’s method parameter.
• Annotation ModelAttribute The form data can be read and bound to a Java object with the help of the ModelAttribute annotation.
• To read HTML from user data, the HttpServletRequest interface—a Java interface—is utilized.

53. What are your thoughts on Spring MVC validations?

Ans:

Spring MVC calls user-input data validation validation. It is among Spring MVC’s most crucial components. It limits what the user can enter as data. Bean Validation API must be used to validate the user input. A custom validation annotation can also be specified at the class level to validate several class attributes. Finding the matching values in two class fields is a typical use case.

54. By the Bean Validation API, what do you mean?

Ans:

This Java specification allows limitations to be applied to a method, class, or field of a JavaBeans component in the form of annotations. We can confirm a length, regular expression, number, etc.The JavaTM Enterprise Edition 6 platform introduces the Bean Validation API as a standard mechanism to validate JavaBeans in an application’s display, business, and data access layers. JavaBeans were validated in each tier prior to the Bean Validation definition.

55. What key distinction exists between Controller and RestController?

Ans:

The components annotation is specialized into the Controller and Rest Controller. The ResponseBody annotation is the primary difference between them. Not every Controller receives an independent call from Controller to ResponseBody. On the other hand, the Rest Controller calls ResponseBody to all controller functions while using both Controller and ResponseBody.

56. What do the annotations RequestBody and ResponseBody mean?

Ans:

RequestBody can be bound to a method parameter using RequestBody. It indicates that the supplied parameter needs to be translated from the incoming request. The response body of the controller method consists of its serialized return type, which ResponseBody ensures.

57. What do the terms “Model,” “ModelMap,” and “ModelAndView” mean?

Ans:

• Model and View can be considered a bucket containing both model map and View, and the model as an interface and mode map as a class. 
• ModelMap is a class, whereas Model is an interface. 
• ModelAndView is a container for a View object and a ModelMap. It enables a controller to return both as a single value.

58. What do SessionAttributes and SessionAttribute signify to you?

Ans:

Web applications’ session data is managed by using SessionAttributes and SessionAttributes. Several model attributes are kept in the session and made accessible for subsequent requests within the same session when utilizing SessionAttributes. To connect specific model attributes from a session to the method argument, use the SessionAttribute class.

59. What do spring MVC tiles mean?

Ans:

Spring MVC Tiles is an integration of the Apache Tiles library with the Spring MVC framework. Using Apache Tiles, a templating framework, you can create reusable views and layouts for your internet-based program. This is beneficial for designing consistent modular user interfaces. With Spring MVC Tiles, web pages can be made by piecing smaller, reusable “tiles” into a more extensive page layout. Each tile represents a page section, content section, sidebar, header, or footer.

60. What does EnableWebMVC mean? Describe its objective.

Ans:

• Use the EnableWebMVC annotation to activate Spring MVC in an application. It is primarily employed in configuration classes. 
• EnableWebMVC’s primary goal is to handle and process requests and responses. 
• It specifies callback methods to personalize the Java-based Spring MVC configuration activated by the EnableWebMvc setting. 

61. What is the purpose of Spring MVC?

Ans:

A Java framework called Spring MVC is used to create web apps. It adheres to the model-view-controller design pattern and incorporates all of the fundamental Spring framework features, including Dependency Injection and Inversion of Control.

62. What are Spring MVC’s layers?

Ans:

The Presentation Layer (Controller), Business Logic Layer (Service), Data Access Layer (Repository or DAO), Model Layer, View Layer (JSP, Thymeleaf, etc.), and Integration Layer make up the layers of the Spring MVC architecture. This tiered strategy encourages modular architecture and improves web application maintainability.

63. What is the Spring MVC life cycle?

Ans:

After exiting the browser, a request first reaches Spring’s DispatcherServlet. The DispatcherServlet is responsible for sending the request to a Spring MVC controller. After receiving the request, the Controller processes it and sends the result to the browser.

64. What are Spring MVC’s salient characteristics?

Ans:

• Spring MVC has features that allow business code to be reused without duplication. You can also adjust the view resolution and handler mapping. 
• This will enable adaptable model transfer through Map. 
• It offers validation and binding customization. 
• You can customize the application classes and framework by using Spring MVC.

65. What distinguishes spring boot from Spring MVC?

Ans:

While Spring Boot simplifies the development of Spring-based apps, Spring MVC is a framework for creating web applications with MVC architecture. Whereas Boot offers prepackaged modules for developing and deploying Spring programs, MVC concentrates on web apps.

66. What subjects are covered in depth in Spring MVC?

Ans:

• Spring MVC covers controllers, Views, Models, Request Mapping, Data Binding, Validation, Interceptors, and Exception Handling. 
• These subjects offer fundamental building blocks for using the Spring MVC framework to create web applications.

67. What is the purpose of the Spring Framework?

Ans:

• Spring is a practical open-source, somewhat lightweight, linked Java framework designed to make creating enterprise-level applications less complicated. 
• The “framework of frameworks” moniker comes from Spring’s ability to support numerous other significant frameworks, including JSF, Hibernate, Structs, EJB, and others.
• About 20 modules total, which can be broadly classified into the following categories:
• AOP (Aspect Oriented Programming) o Core Container o Data Access/Integration o Web o Instrumentation o Messaging o Test

 68. What characteristics does the Spring Framework have?

Ans:

• Spring’s AOP (Aspect Oriented Programming) feature facilitates unified development by guaranteeing that the business logic of an application is isolated from other system functions.
• Spring offers an incredibly adaptable MVC web application framework with simple framework-switching capabilities.
• Offers configuration creation and management services and application object lifecycle definition.
• One unique design principle in Spring is IoC (Inversion of Control), which allows objects to declare their dependencies instead of searching for ways to create dependent objects.
• Spring is a small, loosely linked framework with a Java foundation.
• Spring offers a generic abstraction layer for managing transactions, which is highly beneficial in contexts without containers.

69. What is a configuration file for Spring?

Ans:

A Spring configuration file is an XML file that primarily describes the classes’ Configuration and links to one another, along with their information. The configuration files in XML are more concise and clear. Offers configuration creation and management services and application object lifecycle definition. Spring offers an easy-to-use API for converting technology-specific exceptions (thrown by Hibernate, JDBC, or other frameworks) into unchecked, consistent errors. This significantly streamlines exception handling and introduces abstraction.

70. What characteristics does the Spring Framework have?

Ans:

• The layered architecture pattern used by the Spring framework facilitates the selection of essential components and offers a stable and well-organized framework for creating J2EE applications.
• Spring’s AOP (Aspect Oriented Programming) feature facilitates unified development by guaranteeing that the business logic of an application is isolated from other system functions.
• Spring is a highly flexible MVC web application framework that may be quickly converted to another framework.
• One unique design principle of Spring is IoC (Inversion of Control), which allows objects to declare their dependencies instead of searching for and generating dependent objects.

71. What is a configuration file for Spring?

Ans:

In essence, a Spring configuration file is an XML file that primarily explains how the classes are related and contains information about them.  The configuration files in XML are more concise and clear. Spring offers an easy-to-use API for converting technology-specific exceptions (thrown by Hibernate, JDBC, or other frameworks) into unchecked, consistent errors. This significantly streamlines exception handling and introduces abstraction.

72. Describe the distinction between setter and constructor injection in question 

Ans:

• Within  Partial Injection is permitted in setter injection but not constructor injection.
• Unlike setter injection, which does not override the setter property, constructor injection does not.
• Any modifications made result in creating a new instance via constructor injection. Setter injection prevents the creation of new instances.
• Constructor injection is the recommended method if the Bean has numerous characteristics. Setter injection is recommended if it has minimal qualities.

73. What are Allowances?

Ans:

• The Spring IoC container is in charge of these objects, which serve as the framework for the user’s application.
• IoC containers are used to instantiate, configure, wire, and manage spring beans.
• The configuration metadata that users provide to the bean creation container (using Java annotation settings or XML annotations).

74. What does the “Inversion of Control” (IoC) container mean?

Ans:

The foundation of the Spring Framework is the Spring container. Dependency Injection (DI) is the spring container’s mechanism for managing the application components. It creates objects, wires them up, configures their general life cycles, and manages them. Java annotations, Java code, or XML configuration can all be used to give the spring container instructions.

75. What does Dependency Injection mean to you?

Ans:

The fundamental tenet of dependency injection is that you must provide the proper way for your objects to be generated rather than creating them.

There are two main approaches to accomplishing dependency injection in Java:

• Constructor injection: In this scenario, the IoC container calls the class constructor with several arguments, each of which represents a dependency on a different class.
• Setter injection: In this case, the beans are instantiated by the spring container using a default constructor or a no-argument static factory method.

76. Could you clarify the distinction between setter and constructor injection?

Ans:

• Partial Injection is permitted in setter injection but not in constructor injection.
• In contrast, the constructor injection does not override the setter property. This isn’t the case with setter injection.
• Any modifications made result in creating a new instance via constructor injection. Setter injection prevents the creation of new cases.
• Constructor injection is the recommended method if the Bean has numerous characteristics. Setter injection is recommended if it has minimal qualities.

77. What Are Spring Vegetables?

Ans:

• The Spring IoC container is in charge of these objects, which serve as the framework for the user’s application.
• IoC containers are used to instantiate, configure, wire, and manage spring beans.
• The configuration metadata that users provide to the container (via XML or Java annotation configurations) is used to build beans.
• To learn the basics of Java, check out Scaler Topics’ Free Java Spring Boot course.

78. How does the spring container receive the configuration metadata?

Ans:

The configuration metadata can be provided in three different ways. They are listed in the following order:

• Config based on XML: XML configuration files include the bean configurations and their dependencies. As seen below, this begins with a bean tag:
• Annotation-based Configuration: By annotating the pertinent class, method, or field declaration, the beans can be configured directly into the component class as an alternative to the XML technique.
• Annotation wiring is not enabled by default in the Spring container. As indicated below, it must be enabled in the Spring XML configuration file.
• Java-based Configuration: The Spring Framework included important functionalities as part of fresh support for Java configuration. This uses the Bean annotated methods and Configuration annotated classes.

79. Which bean scopes are offered in the Spring?

Ans:

There are five scope supports in the Spring Framework. They are as follows:

• Singleton: When utilizing this, the bean definition’s scope is limited to one instance per IoC container.
• Prototype: In this case, an object instance can be the scope of a single bean specification.
• Request: An HTTP request is the scope of the bean specification.
• Session: In this case, HTTP-session is the scope of the bean specification.
• Worldwide Session: The Range of a Global HTTP session is the Bean’s definition in this case.

80. Describe how beans grow in a container at the Spring Bean Factory.

Ans:

• The Bean is instantiated by the IoC container using the bean definition in the XML file.
• As stated in the bean definition, Spring uses dependency injection to fill all properties.
• The bean factory container invokes setBeanName(), which requires the appropriate Bean to implement the BeanNameAware interface and takes the bean ID as input.
• If the Bean implements the BeanFactoryAware interface, the factory then calls setBeanFactory() and passes an instance of itself.

81. Based on Bean Wiring, what do you understand?

Ans:

The term “bean wiring” refers to mixing beans inside a Spring container. When wiring beans, the Spring container should know which beans are required and how they depend on one another. This is provided via Java code-based configuration, XML, and annotations.

82. Describe auto wiring and list its many modes.

Ans:

The IoC container authors the relationships between the application beans. Spring allows collaborators to examine the BeanFactory’s contents to determine which Bean requires automatic wiring.

Some of this process’s modes are:

• No: This is the default value and indicates no auto wiring. For wiring, an apparent bean reference must be utilized.
• byName: The Dependency is injected depending on the Bean’s name. By the Configuration, this matches and wires its attributes with the beans defined by the same names.
• byType: Depending on the type, this injects the bean dependency.
• constructor: In this case, the class constructor is called to inject the bean dependency. There are a lot of factors involved.
• autodetect: If auto wiring by the constructor cannot be accomplished, the container attempts auto wiring by byType.

83. What are auto wiring’s limitations?

Ans:

• Overriding possibility: Using and setting dependencies that override auto wiring can be specified.
• Data types restriction: Autowiring is impossible for primitive data types, Strings, or classes.

84. What does the phrase “Spring Boot” mean to you?

Ans:

An open-source, Java-based framework called Spring Boot offers a platform for creating production-ready, stand-alone spring apps with minimal configuration requirements. It also supports Rapid Application Development.

85. Describe the benefits of developing applications with Spring Boot.

Ans:

• Spring Boot facilitates the development of stand-alone apps that require no configuration of WAR files and may be launched with java.jar.
• Maven configuration can benefit from specific “started” POMs provided by Spring Boot.
• Offers direct embedding of Tomcat, Jetty, Undertow, and other web servers.
• Auto-Configuration: This feature enables an application to be configured automatically per the dependencies on the classpath.
• The goal of developing Spring Boot was to write fewer lines of code.
• It provides production-ready support such as monitoring and makes it simpler to launch programs created using Spring Boot.

86. What are the names of the annotations that are used to manage the various incoming HTTP request methods?

Ans:

The following annotations handle different incoming HTTP request methods: 

• PutMapping 
• GetMapping 
•  PostMapping 
•  PatchMapping 
•  DeleteMapping

87. What characteristics does Spring Boot offer?

Ans:

• CLI for Spring Boot: This Spring Boot CLI: This eliminates boilerplate code and lets you write Spring Boot applications using Groovy or Maven.
• Starter Dependency: This feature allows Spring Boot to group similar dependencies, which gradually boosts output and lessens the strain on
• Spring Initializer: This web application aids in the creation of an internal project structure by developers. This functionality spares the developer from manually setting up the project’s structure.
• One helpful feature is Auto-Configuration, which loads the default configurations based on the project you are working on. This method avoids unnecessary WAR files.
• Spring Actuator: Spring Boot provides “Management EndPoints” through the actuator, which aids developers in reviewing application internals, metrics, and other information. Logging and Security – This guarantees that all Spring Boot applications are hassle-free and appropriately secured.

88. What internal functions does the SpringBootApplication annotation serve?

Ans:

According to the Spring Boot documentation, the SpringBootApplication annotation can be used in place of the Configuration, EnableAutoConfiguration, and ComponentScan annotations, along with their default characteristics. This reduces the number of lines of code by allowing the developer to use a single annotation rather than several. Nonetheless, we can use these annotations in accordance with our projects’ requirements because Spring offers loosely coupled capabilities.

89. What happens when a Spring Boot application is executed as a “Java Application”?

Ans:

As soon as the application detects that we are running a web application, it starts the Tomcat server automatically. It automatically manages configuration and dependencies without specifying the version of those requirements. Profile-specific properties: The YAML file or the application-{profile}.properties file is used to load these properties. The {profile} placeholder denotes an environment or an active profile, and the file is located in the same place as the non-specific property files.

90. Where may the external Configuration come from?

Ans:

By utilizing Spring Boot’s external configuration functionality, developers can run the same application in many settings. To list the necessary configuration properties for each environment, this uses environment variables, properties files, command-line arguments, YAML files, and system properties. The sources of external Configuration are as follows:

• Command-line properties: Spring Boot adds properties to the collection of environment properties after supporting command-line arguments and converting them to properties.
• Application Properties: Spring Boot currently looks for the YAML file or application properties file. To load the properties, navigate to the Configuration, classpath root, or application directory.

91. Is it possible to modify the integrated Tomcat server’s default port in Spring Boot?

Ans:

You can modify it by adding a property called server. Port to the application properties file and assign it to any port you choose. For instance, you must provide a server.port=8081 if you want the port to be 8081. The application properties file will be loaded immediately upon mentioning the port number. The application will be implemented using Spring Boot and the designated configurations.

92. Is it possible to exclude any package without the basePackages filter?

Ans:

The following is how we can utilize the exclude attribute in conjunction with the annotation SpringBootApplication:

SpringBootApplication(student.class}.exclude=)

public class BitAppConfiguration  {}

93. How may a particular auto-configuration class be turned off?

Ans:

• For this, you may utilize the EnableAutoConfiguration exclusion attribute as demonstrated below:
• Using exclusion = {AutoConfiguration.class}, EnableAutoConfiguration
• We can set the fully qualified name as the value for the excludeName if the class is not specified on the classpath.By utilising EnableAutoConfiguration(excludeName={Foo.class}) and “excludeName”
• The application allows for additions. Keep it separated with commas to add properties and numerous classes.