Master programming syntax, solve interactive challenges & run live code in Syntaxis Explore Arena →

menu_book Course Curriculum (Spring Boot) expand_more

Boot Foundations

SpringBootApplication ConfigurationProperties Bean definition Profiles CommandLineRunner Application events Actuator endpoint Externalized configuration

Web MVC

RestController PathVariable RequestParam RequestBody ResponseEntity ExceptionHandler Validation annotations Multipart upload

Data Access

JPA entity JpaRepository Derived query method JPQL query Pagination Transaction Entity relationship Flyway migration

Production and Security

Spring Security filter chain PasswordEncoder JWT request filter CORS config Caching annotation Async method Scheduled task MockMvc test

Spring Boot / Boot Foundations

CommandLineRunner

Learn CommandLineRunner in Spring Boot through a focused explanation, a topic-specific example, an engineering warning, and a mastery check.

12 min read • Beginner

spring-boot-005.java

java

@Bean CommandLineRunner seed(UserRepository repo){ return args -> repo.save(new User("Ada")); }

What to watch

Content source & attribution

Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

CommandLineRunner Mastery Check →

Application events