hey everyone in this video I want be covering simple and basic questions like what is spring boot or what's the difference between spring and spring boot instead I'll be focusing on real challenging and tricky questions so let's get started how would you handle inter service Communication in a microservice architecture using spring boot so basically for simple direct communication I would use rest template which allows services to send requests and receive responses like a two-way conversation for more complex interactions especially when dealing with multiple Services I would choose fin client basically it simplifies declaring and making the code cleaner and the process would be more efficient for asynchronous communication where immediate responses are not necessary I would use message Brokers like rabbit mq or Kafka these acts like Community boards where Services can post messages that other services can read and act upon later this approach ensures a robust flexible communication system between microservices now let's move to the different question can you explain the caching mechanism available in Spring boot so basically caching is like having a memory box where we can store things we use frequently so we don't have to go through the whole process of getting them each time it makes our application faster and more efficient there is a spring cache abstraction in spring board and it is like a smart memory layer for our operation it is designed to save time and resources by remembering the results of expensive operations like fetching data from a database when we ask from the same data again spring cach gives it to us quickly from its memory instead of doing the whole operation again now let's move to the different question how would you implement caching in a spring boot application so in order to implement caching in a spring boot application first add a caching dependencies like spring boot starter cache okay then I'll enable caching in the application by adding enable caching annotation to the main class okay then I'll Define cachable operation using cachable notation on methods whose result we want to cach a okay and uh optionally I will customize cach Behavior with annotations like cach evct and cach put then I'll choose a cache provider like eh cach or hesel cast or I'll use the default concurrent map based cache provided by the spring so this is how I would Implement caching in a spring boot application now let's move to the different question your spring boot application is experiencing performance issues under high load what are the steps you would take to identify and address the performance so first I would identify the specific performance issues using monitoring tools like spring boot actuator or splink then I would also analyze application logs and metrics to spot any patterns or errors especially under high load then I would start a performance test to replicate the issue and use a profiler for code level analysis okay then after getting findings I might optimize a database Implement caching or use scaling option it's also crucial to continuously monitor the application to prevent further issues now let's move to the different question what are the best practices for versioning rest apis in a spring boot application so for versioning rest apis in a spring boot best practices include first is URL versioning it includes the version number in the URL like AP /v/ products okay the second is header versioning it use a customer header to specify the version third one is Media type versioning this version go through the content negotiation using the ex accept header okay fourth is parameter versioning it basically specify the version as a request parameter now let's move to the different question how does spring boot simplify the data access layer implementation basically spring boot uh makes the implementation of data access layer Easy by offering several streamlined features first it autoc configures essential settings like data source and jpa based on the libraries present in the class path and will reduce the manual setup it also provides built-in repository support such as jpa repository enabling easy cred operations without the need for boiler plate code additionally spring boot can automatically initialize database schemas and will seed the data using script it also integrates smoothly with various databases and or Technologies and translate SQL exception into Springs data access exceptions and providing a consistent and simplified error handling mechanism these features collectively make data access layer development more efficient and developer friendly now let's move to the different question what are conditional annotations and explain the purpose of conditional annotations in Spring boot so basically conditional annotations in Spring boot help us create beans or configurations only if certain conditions are met it's like setting rules if this condition is true then do this a common example is conditional on class annotation which creates a bean only if a specific class is present this makes our application flexible and adaptable to different environments without changing the code and it will enhance the modularity and efficiency as well now let's move to the different question explain the role of enable autoc configuration annotation in a spring boot application and how does a spring boot achieve autoc configuration internally in Auto configuration annotation in Spring boot tells the framework to automatically set up the application based on its dependencies internally spring boot uses conditional evaluation that will examine the class path existing beans and properties it depends on conditional annotation in its autoc configuration classes to determine what to configure this smart setup makes the configuration to our needs it will simplifying and speeding up the development process now let's move to the different question what are spring boot actuator endpoints spring boot actuator is like a toolbox for monitoring and managing our spring boot application it gives us endpoints where we can check Health view configurations gather metrics and much more it's super useful for keeping an eye on how our app is doing in a production environment which is like the real world where our app is being used by people these endpoints can reveal sensitive information about our application imagine leaving our diary opening public place we wouldn't want that right similarly we don't want just anyone seeing into the internals of our application now let's move to the different question how can we secure the actuator endpoints so basically there are few ways to secure the actuator endpoints first one is limit exposure by default not all act actuator endpoints are exposed we can control which ones are available over the web it's like choosing what parts of our da are okay to share okay second is using Spring Security we can configure Spring Security security to require authentication for accessing act points we should use https instead of HTTP since https is having more security fourth one is actuator role we should create a specific role like actuator admin and assign it to users who should have access this is like giving a key to only trusted people now let's move to the different question what strategies would you use to optimize the performance of a spring boot application let's say my spring boot application is taking too long to respond to user request I could Implement caching for frequently Access Data optimize database queries to reduce the load on the database use a synchronous method for operations like sending emails load balancer if traffic is high optimize the time complexity of the code use webflex to handle a large number of concurrent connections now let's move to the different question how can we handle multiple beans of the same type to handle multiple beans of the same type in a spring we can use qualifier annotation this lets us specify which beans to inject when there are multiple candidates for example if there are two beans of the type data source we can give each a name and use qualifier to tell spring which one to use another way is to use primary anotation on one of the beans marking it as a default Choice when injecting that type now let's move to the different question what are some best practices for managing transaction in Spring boot application so first we should use transaction a so basically transactional annotation is one of the annotations in Spring boot that we put on method or classes it tells spring boot hey please handle this as a single transaction then put transaction annotation on service methods where we perform the database operations if anything goes wrong with this method spring boot will automatically roll back the changes to avoid partial updates okay second one is to keep transaction at the service layer basically it's usually best to handle transaction in the service layer of our application the service layer is where we put business logic it's a sweet spot where we can access different parts of our application like data access and business logic while keeping things organized now let's move to the different question how do you approach testing in Spring boot application testing in Spring boot applications is like making sure everything is our newly built rocket works perfectly before launching it into a space we want to be sure each part does its job correctly in a spring board we have some great tools for this including spring boot test and mock main anotation uh let's first uh see the testing approach first one is unit testing this is like checking each part of our rocket individually like the engine the fuel tank Etc we test small pieces of code usely methods in isolation second approach is integration testing now we are checking how different parts of our rocket work together in a spring boot this means testing how different components interact with each other and with the spring context now let's move to the different question discuss the use of spring boot test and mock beIN annotations so first let's understand the spring boot test annotation spring boot test is an annotation used for integration testing in Spring boot it says start up the spring context when this test runs use spring boot test annotation when we need to test how different parts of our application work together it's a great way for when we need the full behavior of our application now let's understand the mo bin annotation Moog bin is used to create a Moog version of a component of service is this is useful when we want to test a part of our application without actually involving its dependencies use mock pin in test where we need to isolate the component being tested for example if we are testing a service that depends on a repository we can mock the repository to control how it behaves and test the service in isolation now let's move to the different question what advantages does yl offers over properties file in Spring boot are there limitations when using yl for configuration so basically yl several advantages over properties file in spring board it supports hierarchal configuration which are more readable and easier to manage especially for complex structures EML also allows commments aing documentation however EML has limitations too it's more error prone due to its sensitivity to spaces and indentations additionally yaml is less familiar to some developers compared to straightforward key value format pair of properties file file EML is a great for complex configurations and readability these limitations are important to consider when choosing the format for spring boot application now let's move to the different question explain how spring boot profile Works Spring boot profiles are like having different settings for our application depending on the situation it's like having different playlist on our music app one for working out one for relaxing and so on each playlist sets a different mood just like each profile in Spring boot sets up a different environment for our application profile and spring boot allow us to separate parts of our application configurations and make it available only in certain environments for example we might have one set of settings for development another for testing and yet another for production so let's understand why should we use profiles using profiles helps keep our application flexible and maintainable we can easily switch environments without changing our code it's like having different mode for different purposes making sure our application always behaves appropriately for its current environment now let's move to the different question what is aspect oriented programming in the spring framework basically aspect oriented programming is a programming approach that helps in separating concerns in our program especially those that cuts across multiple parts of an application a main program code focuses on the core functionality while the aspects take care of the other common task that needs to happen in various places like logging Security checks or managing transactions for example in Java application we might have methods where we want to log information every time they are called or checked that a user has a right permission instead of putting this logging or security code into every method we can Define it once in an aspect and then specify where and when this code should applied across our application this keeps our main code cleaner and more focused on its primary task let's move to the different question what is spring cloud and how it is useful for building microservices spring cloud is one of the components of the spring framework it helps managing microservices imagine we are running an online store application like a virtual mall where different sections handle different task in this application each store or section is a micros service one section handles customer login another manages the shopping card one take care of processing payments and another list all the products building and managing such an app can be complex because we need all these sections to work together seamlessly customer should be able to login add items to the card pay for them and browse products without any problem that's where spring Cloud comes into the picture it helps microservices in connecting the SE section balancing the crowd keeping the Secret Safe etc etc now let's move to the different question how does spring boot make the decision on which server to use a spring boot decides which server to use based on the class part dependencies if a specific server dependency like Tomcat jti or andto is present spring boot autoc configures it as a default server if no server dependency is found spring boot defaults to tomat as it's included in Spring boot starter web this automatic server selection simplifies setup and configuration allowing us to focus more on developing the application rather than configuring server detail how to get the list of all the beans in your spring boot application so first I would autowire the application context into the class where I want to list the beans as you can see in the code then I would use the get bean definition names method from the application context to get the list of beans now let's move to the different question describe a spring boot project where you significantly improved performance what techniques did you use so I improved a spring boot project performance by optimizing database interactions with connection pooling and caching by using eh cache I also enabled HTTP response compression and configured stateless sessions in Spring Security to reduce the data transfer and session overhead I also significantly reduced response Times by using spring boots actuator for realtime monitoring and adapting a synchronous processing for non-critical task I increase the application ability to handle more concurrent users enhancing overall efficiency let's move to the different question explain the concept of spring boot's embedded serlet containers so basically spring boot has an embedded serlet container feature which essentially means it has a web server like Tomcat jety or under built right into the application this allows us to run our web applications directly without setting up an external server it's a big time saver for development and testing because we can just run our application from our development environment or through a simple command this embeded approach simplifies deployment to as our application becomes a standalone package with everything need to run it and it will eliminate the need for separate web server configuration now let's move to the different question how does spring boot make di easier compared to traditional spring so basically spring boot makes dependency injection easier compared to traditional Spring by autoc configuring beans and reducing the need for explicit configuration in traditional spring we had to Define beans and their dependencies in XML files or with annotations which can be complex for large applications but in Spring boot we use Auto configuration and component scanning to automatically discover and register beans based on the application's context and class PA this means now we don't have to manually wire up beans spring boot intelligently figures out what's needed and configures it for us this autoconfiguration feature simplifies application setup and development allowing us to focus more on writing business logic rather than the boilerplate configuration code now let's move to the different question how does a spring boot simplify the management of application secrets and sensitive configurations especially when deployed in different environments so basically spring boot helps manage application Secrets by allowing configuration to be externalized and kept separate from the code this means I can use properties files EML files environment variables and command line arguments to Just Adjust setting for different environments like development testing and production for sensitive data spring boot can integrate with systems like spring Cloud config server or Hashi cob Walt which securely stores and provide access to Secrets this setup simplifies managing sensitive configurations without hardcoding them enhancing security and flexibility across various deployment environments now let's move move to the different question explain spring boot's approach to handle asynchronous operations so basically spring boot uses The asyn annotation to handle asynchronous operations this let us run task in the background without waiting for them to be complete before moving on to the next line of the code to make a method asynchronous we just add a sync annotation above its definition and spring take care of running it in a separate thread this is Handy for operations that are independent and can be run in a parallel like sending emails or processing files so the main flow of the applications doesn't get blocked to work with ESS sync operations we also need to enable it in configurations by adding enable async annotation to one of the configuration classes now let's move to the different question how can you enable and use asynchronous methods in a spring boot application to enable and use asynchronous method in a spring boot application first I would add the enable ASN anotation to one of my configuration classes this enables Springs asynchronous method execution capability abilities next I would Mark methods I want to run asynchronously with The async annotation these methods can return void or future type if I want to track the result finally I would call these methods like any other method spring take care of running them in a separate thread allowing the calling thread to proceed without waiting for the task to finish remember for The async annotation to be effective the method calls must be made from outside the class if I call an asynchronous method from within the same class it won't execute asynchronously due to the Way Spring proxies work now let's move to the different question describe how you would secure sensitive data in a spring boot application that is access by multiple users with different roles to keep sensitive information safe in a spring boot app used by many people with different roles I would do a few things first I would make sure everyone who uses the app provs who they are through a login system then I would use a special setting to control what each person can see or do in the app based on their role like some can see more sensitive stuff while other can't I would also scramble any secret information stored in an app or sent over the Internet so that only the right people can understand it plus I would keep passwords and other Secrets keys out of the code and keep them in a safe place making them easy to change if needed lastly I would keep track of who looks at or changes the sensitive information just to be extra safe this way only the right people can get the sensitive data and it's stay protected now let's move to the different question you are creating an endpoint in a spring boot application that allow users to upload files explain how you would handle the file upload and where you would store the files to handle file upload in a spring boot application I would use post mapping annotation to create an endpoint that listen for post requests then I would add a method that accepts multiart file as a parameter in the controller this method would handle the incoming file now let's move to the different question can you explain the difference between authentication and authorization in Spring Security in Spring Security authentication is verifying who I am like showing an ID it checks my identity using methods like password or tokens authorization decides what I am allowed to do after I am identified like if I can access certain parts of an app it's about permissions so authentication is about confirming my identity and authorization is about my exis rights based on that identity now let's move to the different question after successful registration your spring boot application needs to send a welcome mail to the user describe how would you send the emails to the registered users first I would ensure the spring boot starter mail dependency is in my projects form XML next in application. properties file I would set up my mail server details like host Port username and password then I would write a service class that uses Java mail sender to send emails in this service I craft the welcome email content and use the a send method to dispatch emails and finally after a user successful registers I would call my mail service from within the registration logic to send the welcome email now let's move to the different question what is spring boot CLI and how to execute the spring boot project using boot CLI spring boot CLI is a tool for running spring boot application easily it helps to avoid boilerplate code and configuration to execute the spring boot project using boot CLI first install the CLI through a package manager or download it from the spring website write the application code in a groovy script which allow using spring boot features without detailed configuration in the terminal navigate to The Script directory and run spring my app. groovy substituting my. grovy with the scripts file name now let's move to the different question how is a Spring Security implemented in a spring boot application to add the Spring Security in a spring boot application first we need to include a Spring Security starter dependency in the pal file then we create a configuration class extending web security configurer adapter to customize security settings such as specifying secured endpoints and configuring the login and log out process we also implement the user Detail Service interface to load user information usually form a database and use a password encoder like bcrypt password encoder for secure password storage we can secure specific endpoints using annotation like pre-authorized based on roles or permission this setup ensures that my spring boot application is secure managing both authentication and authorization effectively now let's move to the different question how to disable a specific autoc configuration to disable a specific Auto configuration in a spring boot application I use the exclude attribute of the spring boot application annotation first I find out which autoc configuration class I want to disable for example let's say I want to disable the auto configuration class for data source then I update spring boot application annotation with exclude keyword as shown shown Below in the code exclude is equal to data source autoconfiguration do class now let's move to the different question explain the difference between cash eviction and cach expiration cach eviction is when data is removed from the cachier to free up space based on a policy like least recently used cash expiration is when data is removed because it's too old based on a predetermined time to live so eviction manages caches size while expiration ensures data freshness now let's move to the different question if you had to scale a spring boot application to handle high traffic what strategies would you use to scale a spring boot application for high traffic we can add more app instances like horizontal scaling and use a load balancer to spread out the traffic break up our application into microservices so each part can be scaled independently use cloud services that can automatically adjust resources based on our apps need use caching to store frequently accessed data reducing the need to fetch it from the database every time and then I can also Implement an API Gateway to handle requests and take care of things like authentication now let's move to the different question describe how to implement Security in a microservices architecture using spring Boot and Spring Security to secure microservices with spring Boot and Spring Security we add the Spring Security to each microservices for authentication or authorization create a central authentication Service that gives out tokens like jot when users log ensure each microservice checks these tokens to let only allowed users in use SSL TLS for secure communication Implement an API Gateway to manage security checks and Route requests in spring board how is session management configured and handled especially in distributed systems in spring board for distributed systems session management is done by storing session information in a shared location using spring session this way any server can access the session data allowing user users to stay logged in in across different servers we set it up by adding spring sessions to our project and choosing where to store the sessions like in a database or Cache this makes our application more scalable and keep user session consistent now let's move to the different question imagine you are designing a spring boot application that interfaces with multiple external apis how would you handle API rate limits and failures to handle API rate limits and failures in a spring boot application I would use a circuit breaker to manage failures Implement rate limiting to avoid exceeding API limits add a retry mechanism with exponential backup for temporary issues user caching to reduce the number of request this approach helps keep the application riable and efficient now let's move to the different question how would you manage externalized configuration and secure sensitive configuration properties in a microservice architecture to handle these settings across microservices in a big project I would use a tool called sping Cloud config it's like having a central folder where all settings are kept this folder can be on the web or my computer there's a special app called config server that gives out these settings to all the other small applications or microservices where they ask for it if there are any secret settings like password I would make sure they are scrambled up so no one can easily see them this way all microservices can easily get updated settings they need to work right and the important stuff stay safe can we create a non-web application and spring boot yes we can make a non- web application with spring boot spring boot is not just for Web projects we can use it for other types like running scripts or processing data if we don't add web parts to our project it won't start a web server instead we can use a feature in Spring boot to run our code right after the program starts This Way Spring boot helps us build many different types of applications not just websites now let's move to the different question what does spring boot application annotation do internally so spring boot application annotation is like a shortcut that combines three other annotations first it uses configuration telling spring that this class has configurations and beans that spring should manage then it uses enable auto configuration which allows the spring boot to automatically set up the application based on the libraries on the class path lastly it includes component scan which tells spring to look for other components configuration and services in the current package allowing it to find and register them now let's move to the different question how does spring boot supports internationalization spring boot supports internationalization by showing our applications text in different languages by using properties file we put these files in a folder named Source main resources each file has a name like message XX in properties file where access stands for language code spring boot uses these files to pick the right language based on the user settings we can set rules on how to choose the user's language with something called local resolver this way application can speak to users in their language making it more user friendly for people from different parts of the world now let's move to the different question what is the spring boot Dev tools used for spring boot Dev tools is a tool that makes developing application faster and easier it automatically restarts our application when we change code so we can see updates immediately without restarting manually it also refreshes our web browser automatically if we change things like HTML files def tools also provide shortcuts for common task and helps with fixing problems by allowing remote debugging basically it's like having a helpful assistant that speed UPS our work by taking care of repeated task and letting us focus on writing and improving our code now let's move to the different question how can you mock external services in a spring boot test in a spring boot test we can mock external services using the mock bin annotation this annotation lets us create a mock version of an external service or repository inside our test environment when we use mock beIN spring boot replaces the ual be with the mock in the application context then we can Define how this mock should behave using mocking Frameworks like mockito specifying what data to return When certain methods are called this approach is super helpful for testing our applications logic without actually calling external Services making our test faster and more relable since they don't depend on the external systems being available or behaving consistently now let's move to the different question how do you mock microservices during testing to mock microservices during test I use tool like wir Mo or mokito to pretend I am talking to real services with these tools I set up a fake responses to our request so if my app ask for something from other service the tool steps in and give back what I told it to just like if the real service had answered this method is great for testing how our app works with other services without needing those services to be actually running making our test quicker and more rable now let's move to the different question explain the process of creating a Docker image for a spring boot application to make a Docker image for a spring boot application we start by writing a Docker file this file tells Docker how to build our apps image we mention which Java version to use add our apps jar file and specify how to run our app after writing the docker file we run a command Docker like this in the terminal this command tells Docker to create the image with everything our app needs to run by doing this we can easily run our spring boot application and anywhere Docker is available making our apps more portable and easy to deploy now let's move to the different question discuss the configuration of spring boot security to address common security concerns to make my spring boot application secure I would set up a few things with Spring Security First I would make sure users are who they say they are by setting up a login system this could be a simple username and password form or using accounts from other services next I would control what parts of our application each user can access based on their roles I would also switch on https to keep data safe while it's being sent over the Internet Spring Security helps stop common WebEx like csrf by default so I would make sure that turned on plus I would manage user sessions carefully to avoid anyone hijacking them and I would Store password securely by using strong hashing this way I'm covering the basics to keep the app and its user safe now let's move to the different question discuss how would you secure a spring boot application using Json web token to use a Json web application for securing a spring boot application I would set it up so that when users login they get a jot this tokens has its detail and permissions for every action the users want to do afterward the app checks this token to see if they are allowed I would use a special Security checks in Spring boot to grab and check the jot on each request making sure it's a valid this way the app doesn't have to keep asking the database who the user is making things faster and safer especially for apps that have a lot of users or need to be very secure now let's move to the different question how can spring boot application be made more resilient to failures especially in microservices architecture to make spring boot apps stronger against failures especially when using many services together we can use tools and techniques like circuit breakers and ret with libraries like resilience 4J a circuit breaker stops calls to a service that doesn't work right helping prevent bigger problems retry logic tries the call again in case it fails for a minor reason also setting up timeouts helps avoid waiting too long for something that might not work plus keeping an eye on the system with good logging and monitoring let spot and fix issues fast this approach keeps the app running smoothly even when some parts have trouble now let's move to the different question explain the conversion of business logic into serverless functions which spring Cloud function to make serverless function with spring Cloud function we can write our business task as simple Java functions these are then set up to work as serverless functions which means they can run on cloud platforms without us having to manage a server this setup lets our code automatically adjust to more or fewer request saving money and making maintenance easier basically we focus on the code and spring Cloud functions handles the rest making it ready for the cloud now let's move to the different question how can spring Cloud Gateway be configured for routing security and monitoring for routing we Define routes in the application Properties or through Java config specifying paths and destination for incoming requests for security we integrate Spring Security to add authentication authorization and protection against common threats to enable monitoring we use a spring actuator which provides built-in endpoints for monitoring and managing the Gateway this setups allows us to control how requests are handled secure the Gateway and keep an eye on its performance and health all within the spring ecosystem now let's move to the different question how would you manage and monitor a synchronous task in a spring boot application ensuring that you can track task progress and handle failures I would ingate with a messaging system like rabit mq or Apachi Kafka first I would add the necessary dependencies in my P XML file or gdel file then I would configure the connection to the message broker in my properties or EML file specifying details like the host port or credentials next next I would use Springs enable messaging annotation to enable messaging capabilities and create a bean annotation to define the queue exchange and binding to send messages I would autowire the Kafka template and use it send or convert and send method passing the message and destination now let's move to the different question your application needs to process notifications asynchronously using a message cue explain how you would set up the integation and send messages from your spring boot application to manage and monitor asynchron run task in a spring boot application I would use The asnc annotation to run task in the background and completable future to track their progress and handling results or failures For Thread management I would configure a threadpool task executor to customize thread settings to monitor these task I would integrate spring boot actuator which provides insights into application health and metrics including threatful usage this combination allow me to efficiently run task asynchronously monitor their execution and ensure proper error handling keeping the app responsive and rable moving to the next question you need to secure a spring boot application to ensure that only authenticated users can access certain end points describe how you would configure Spring Security to set up a basic form based authentication first I would start by adding the Spring Security dependency to my project I would configure a web security configur adapter to customize security settings in this configuration I would use the HTTP do authorized request method to specify which which endpoints require authentication I would enable form based authentication by using HTTP do form login method which automatically provides a login form additionally I would configure users and their roles in the configure method either in memory or through a database how to tell an auto configuration to back away when a bean exist in Spring boot to make an auto configuration step back when a bean already exists we use a conditional on missing Bean annotation this tells spring boot to only create a bean if it doesn't already exist in the context for example if we are Auto configuring a data source but want to back off when a data source p is manually defined we annotate the auto configuration method with conditional on missing Bean we are passing data source class this ensures our custom configuration takes precedence and spring boots Auto configuration will not interfere if the bean is already defined now let's move to the different question how to deploy spring boot web application as a jar and VAR files to deploy spring boot web applications we can package them as either jar or VAR files for a jar file we use spring boots embeded server like Tomcat by running the command mvn package and then Java jar command if we need a war file for deployment on an external service we change the packaging in the P XML to this way ensure the application extends spring Boot tret initializer and then builds with Maven package the v file can then be deployed to any Java CET container like Tomcat or jti now let's move to the different question what does it mean that spring boot supports relaxed binding spring boot relaxed binding means it's flexible in how properties are defined in configuration files the flexibility allows us to use various formats for property names for example if we have a property named server. Port we can write it in different ways like server. Port server hyphen port or server underscore Port spring boot understand these as the same property this feature is especially helpful because it lets us adapt to different environments or personal preferences without changing the way we access these properties in my code it makes spring boot configuration more tolerant to variations making it easier for us to manage and use properties in our applications now let's move to the different question discuss the integration of spring boot applications with cic ID pipelines integration in Spring boot apps with cic pipelines means making the process of building testing and deploying automated when we make changes to our code and push them the pipeline Auto automatically builds the app run test and if everything looks good deploys it this uses tools like genkins or GitHub actions to automate task such as compiling the code and checking for errors if all test pass the app can be automatically sent to a test environment or directly to users these setups help us quickly find and fix errors improve the quality of our app and make update faster without manual steps now let's move to the different question can we override or replace amb Tomcat server in Spring boot yes we can override or replace amb Tomcat server in Spring boot if we prefer using a different server like jti or andto we simply need to exclude Tomcat as a dependency and include the one we want to use in our pal or cradle file springbot automatically configure the new server as the ambid server for our application this flexibility allows us to choose the server that best fits our needs without significant changes to our application making spring board adaptable to various deployment environments and requirements now let's move to the different question how to resolve white label error page in the spring boot application to fix the white label error page in a spring boot application we need to check if our URLs are correctly mapped in the controllers if a URL doesn't match any controller spring boot shows this error page we should add or update our mappings to cover the URLs we are using also we can create custom error Pages or use controller advice annotation to handle errors globally this way instead of the default error page visitors can see a more helpful or custom message when something goes wrong moving to the next question how can you implement pagination in a spring boot application to implement pagination in a spring boot application I use spring data JPS pageable interface in the repository layer I modify my query methods to accept a pageable object as a parameter when calling these methods from my service layer I create an instance of page request specifying the page number and Page size I want this page request is then passed to the repository method spring data jpa hand a pagination login automatically returning a page object that contains the requested page of data along with useful information like total pages and total elements this approach allows me to efficiently manage large data sets by ring only a subset of data at a time moving to the next question how to handle a 404 error in Spring boot to handle a 404 error in Spring boot we make a custom error controller we implemented the error controller interface and Mark it with controller annotation then we create a method that returns our error page or message for 4 or4 errors and we map this method to the error URL using request mapping annotation in this method we can check the error type and customize what users see when they hit a page that doesn't exist this way we can make the error message or page nicer and more helpful moving to the different question how can a spring boot be used to implement even drive and architecture spring board lets us build event drive and architectures by allowing parts of our application to communicate through events we create custom events by making classes that extends application event to send out an event we use application event publisher then we set up listeners with event listener annotation to react to these events this can be done in real time or in the background making our application more modular different parts can easily talk to each other or respond to changes without being directly connected which is great for tasks like sending notification or updating database on events helping keep our code clean and manageable moving to the next question what are the basic annotations that spring boot offers spring boot offers several basic annotation for the devopment springboard application annotation is a key annotation that combines configuration enable auto configuration and component scan annotation setting up the foundation for a spring boot application rest controller and request mapping annotation are essential for creating restful web services allowing us to Define controller classes and map URL paths to the methods service and rep repository annotation Mark service and data access layer respectively promoting separation of concerns autoed annotation enables dependency injection automatically wiring beans these annotations are crucial in reducing boiler prate code speeding up development and maintaining clear architecture making spring boot application easy to create and manage moving to the next question discuss the integration and use of distributed tracing in Spring boot application for monitoring and travel shooting integrating distributed tracing in Spring boot application like with spring cloud sluth or Zipkin helps in monitoring and troubleshooting by providing insights into the application's behavior across different Services when a request travels through microservices these tools assigns and propagate unique IDs for the request creating detailed traces of its Journey this makes it easier to understand the flow pinpoint delays and identify errors in complex distributed environments by visualizing how requests move across Services we can optimize performance and quickly resolve issues enhancing reability and user experience in microservice architecture moving to the next question your application needs to store and retri files from a cloud storage service describe how you would integrate this functionality into a spring boot application to integrate cloud storage in a spring boot application I would use a cloud SDK like AWS SDK for S3 or Google Cloud Storage libraries depending on the cloud provider first I would add the SDK as a dependency in my P or grader file then I would configure the necessary credentials and set settings in application Properties or EML file for accessing the cloud storage I would create a service class to encapsulate the storage operations like uploading downloading and deleting files by Auto wiring these Services where I need it I can interact with cloud storage seamlessly leveraging spring dependencies injection to keep my code clean and manageable let's move to the different question to protect your application from abuse and ensure Fair usage you decide to implement rate limiting on your API endpoints describe a simple approach to achieve this in a spring boot to implement rate limiting in a spring boot application a simple approach is to use a library like bucket 4J or spring Cloud Gateway with built-in rate limiting capabilities by integrating one of these libraries I can Define policies directly on my apis Ando to limit the number of requests a user can make in a given time frame this involves configuring a few annotations or settings in my application properties to specify the rate limits the setups helps prevent abuse and ensures that all the users have Fair access to my application resources maintaining a smooth and riable service moving to the next question for audit purposes your application requires a soft delete feature where records are marked as deleted instead of being removed from the database how would you implement this feature in your spring boot application to implement a soft delete feature in my spring boot application I would add a deleted Boolean column or delete time stamp data time column to my database entities instead of physically removing records from the database I would update this column to indicate a record is deleted in my repository layer I would customize queries to filter out these deleted records from all the fetch operations ensuring they are effectively invisible to the applications this approach allows me to retain the data for audit purposes while maintaining the appearance of deletion providing a balance between data integrity and compliance with deletion requests moving to the next question you are tasked with building a non-blocking reactive rest API that can handle a high volume of concurrent request efficiently describe how you would use a spring webflex to achieve this to build a high performance non-blocking rest API with spring web Flex I would first add spring boot starter web Flex to my project this lets me use Springs reactive features in my controller I would use rest controller annotation and return mono or flux for handling single or multiple data items asynchronously this makes my API efficient under heavy loads by using system resources better for database interactions I would use reactive repositories like reactive current repository ensuring all parts of my application communic nonblocking this setup helps manage lots of concurrent requests smoothly making my API faster and scalable