Find Interview Questions for Java R&D

Right Answer:
A keyframe is a specific point in an animation that defines the starting and ending points of a transition, allowing you to control the intermediate steps in the animation sequence.

Right Answer:
Spring Boot's auto-configuration mechanism automatically configures your Spring application based on the dependencies present in the classpath. It uses the `@EnableAutoConfiguration` annotation, which triggers the loading of various configuration classes defined in the `spring.factories` file. These classes check for specific beans and settings, and if certain conditions are met (like the presence of a specific library), they automatically configure the necessary components, reducing the need for manual configuration.

Right Answer:
To implement security in Spring Boot using Spring Security, follow these steps:

1. **Add Dependencies**: Include the Spring Security dependency in your `pom.xml` or `build.gradle` file.

For Maven:
```xml
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
```

2. **Create a Security Configuration Class**: Extend `WebSecurityConfigurerAdapter` and override the `configure` methods to set up authentication and authorization.

```java
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {
@Override
protected void configure(HttpSecurity http)

Right Answer:
In Spring Boot, you can implement exception handling using the `@ControllerAdvice` annotation along with `@ExceptionHandler` methods. This allows you to define global exception handling for your controllers. You can also use `ResponseEntity` to customize the response. Here's a simple example:

```java
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;

@ControllerAdvice
public class GlobalExceptionHandler {

@ExceptionHandler(Exception.class)
public ResponseEntity<String> handleException(Exception ex) {
return new ResponseEntity<>(ex.getMessage(), HttpStatus.INTERNAL_SERVER_ERROR);
}
}
```

Right Answer:
The `@SpringBootApplication` annotation is a convenience annotation that combines three annotations: `@Configuration`, `@EnableAutoConfiguration`, and `@ComponentScan`. It indicates that the class is the main entry point for a Spring Boot application, enabling auto-configuration and component scanning in the specified package.

Right Answer:
Spring Boot Actuator is a module in Spring Boot that provides production-ready features to help monitor and manage Spring Boot applications. Its main features include:

1. **Health Checks**: Provides endpoints to check the health of the application.
2. **Metrics**: Exposes metrics about the application, such as memory usage and request counts.
3. **Environment Information**: Displays configuration properties and environment variables.
4. **Application Info**: Provides information about the application, like version and description.
5. **Custom Endpoints**: Allows developers to create custom management endpoints.
6. **Security**: Supports securing actuator endpoints to restrict access.

These features help in monitoring and managing applications effectively in production environments.

Right Answer:
A resource in the context of a RESTful API is an object or representation of data that can be accessed and manipulated through the API, typically identified by a unique URL.

Right Answer:
GET retrieves data from a server.
POST sends data to a server to create a new resource.
PUT updates an existing resource with new data.
PATCH partially updates an existing resource.
DELETE removes a resource from the server.

Right Answer:
Authentication in RESTful APIs can be implemented using methods like Basic Auth, OAuth 2.0, or JSON Web Tokens (JWT). Authorization is typically handled by checking user roles or permissions against the requested resource. For example, after authenticating a user, the server can issue a token (like a JWT) that the client includes in subsequent requests to access protected resources, where the server verifies the token and checks the user's permissions.

Right Answer:
To handle errors and exceptions in a RESTful API, use standard HTTP status codes to indicate the type of error (e.g., 400 for bad requests, 404 for not found, 500 for server errors). Include a consistent error response format in the body, providing details such as an error code, message, and any relevant information to help the client understand the issue. Log errors for internal tracking and debugging.

Right Answer:
A URI (Uniform Resource Identifier) is a string that uniquely identifies a resource in a RESTful API, typically in the form of a URL. An endpoint is a specific URI where an API can be accessed by a client to perform operations (like GET, POST, PUT, DELETE) on the resource.

Right Answer:
Kanban focuses on visualizing workflow, limiting work in progress (WIP), and continuous flow. Scrum uses time-boxed iterations (sprints) with specific roles (Scrum Master, Product Owner, Development Team) and events (sprint planning, daily scrum, sprint review, sprint retrospective).

Use Kanban when you need continuous delivery, have evolving priorities, and want to improve workflow incrementally. Use Scrum when you need structured development with fixed-length iterations, have clear goals for each iteration, and benefit from team collaboration with defined roles.

Right Answer:
* **Clear Sprint Goals:** Define specific, measurable, achievable, relevant, and time-bound (SMART) goals for each iteration.
* **Daily Stand-ups:** Facilitate short, focused daily meetings to identify roadblocks and coordinate efforts.
* **Sprint Backlog Management:** Keep the sprint backlog refined, prioritized, and realistic based on team capacity.
* **Timeboxing:** Adhere to time limits for meetings and tasks to prevent scope creep and maintain momentum.
* **Focus on Value:** Prioritize tasks that deliver the most business value within the iteration.
* **Remove Impediments:** Proactively identify and resolve obstacles that hinder the team's progress.
* **Limit Work in Progress (WIP):** Encourage the team to focus on completing tasks before starting new ones.
* **Continuous Feedback:** Regularly review progress, gather feedback, and adapt plans as needed.
* **Defined "Definition of Done":** Ensure a clear understanding of what it means for a task to be considered complete.
* **Team Collaboration & Communication:** Foster open and effective communication and collaboration within the team.

Right Answer:
A sprint backlog is a detailed plan of work for a specific sprint, derived from the product backlog. It's created during sprint planning by the development team, who select items from the product backlog they commit to complete, then break down those items into tasks and estimate the effort required for each.

Right Answer:
Agile ceremonies are recurring meetings within a sprint to facilitate communication, planning, and continuous improvement.

* **Sprint Planning:** The team decides what work to complete in the upcoming sprint. They discuss user stories, estimate effort, and define the sprint goal.

* **Daily Stand-up:** A brief daily meeting where the team shares progress, identifies roadblocks, and coordinates efforts. Each member typically answers: What did I do yesterday? What will I do today? Are there any impediments?

* **Sprint Review:** The team demonstrates the completed work to stakeholders, gathering feedback and ensuring alignment with expectations.

* **Sprint Retrospective:** The team reflects on the past sprint, identifying what went well, what could be improved, and defining action items to enhance future performance.

Right Answer:
Cross-functional teams in Agile are important because they bring together all the necessary skills to complete work without dependencies on other teams. This leads to faster delivery, better problem-solving, and increased innovation. To foster collaboration, encourage open communication, shared understanding of goals, mutual respect, and a focus on collective ownership.