21st Alchemist

What are the advantages of using Spring Boot? Features Create stand-alone Spring applications Embed Tomcat, Jetty or Undertow directly (no need to deploy WAR files) Provide opinionated 'starter' dependencies to simplify your build configuration Automatically configure Spring and 3rd party libraries whenever possible Provide production-ready features such as metrics, health checks, and externaliz..

How do you configure a DataSource in Spring? Dependency Maven org.springframework.boot spring-boot-starter-data-jpa com.h2database h2 1.4.200 runtime Gradle dependencies { implementation 'org.springframework.boot:spring-boot-starter-data-jpa' implementation 'com.h2database:h2' } configuration properties application.yml spring: datasource: url: jdbc:h2:mem:mydb username: sa passwo..

What is Spring Boot? Spring Boot is a tool that makes developing web application and microservices with Spring Framework faster and easier through three core capabilities: Autoconfiguration An opinionated approach to configuration The ability to create standalone applications These features work together to provide you with a tool that allows you to set up a Spring-based application with minimal..

What is the difference between checked and unchecked exceptions? Checked exception Unchecked exception 예외 발생 컴파일시 예외 catch부에서 처리 런타임 도중 발생하는 catch되지 않은 예외 예외 처리 예외처리 필수 예외처리 필수 아님 트랜잭션 처리 롤백하지 않음 롤백함 예시 IOException, SQLException, ClassNotFoundException, InvocationTargetException NullPointerException, IndexOutOfBoundsException, IllegalArgumentException, NumberFormatException Why does Spring prefe..

What is the concept of AOP? Which problem does it solve? What is a cross cutting concern? Name three typical cross cutting concerns. What two problems arise if you don’t solve a cross cutting concern via AOP? What is the concept of AOP? Introduction Aspect-oriented programming (AOP) is an approach to programming that allows global properties of a program to determine how it is compiled into an e..

'dependency injection' definition In software engineering, dependency injection is a technique in which an object receives other objects that it depends on, called dependencies. Typically, the receiving object is called a client and the passed-in object is called a service. The code that passes the service to the client is called the injector. 'Wikipedia' 소프트웨어 공학에서 의존성 주입은 의존이 필..