Spring Boot FAQ: Top Questions

Both are interfaces used to run code after the Spring Boot application has started. They are typically used for initialization logic.

📘 Differences:

• CommandLineRunner accepts raw String arguments.
• ApplicationRunner provides access to parsed ApplicationArguments.

📥 Example:

@Component
public class MyRunner implements CommandLineRunner {
  public void run(String... args) {
    System.out.println("App started!");
  }
}

🏆 Expected Output:

"App started!" printed on console after context loads.

🛠️ Use Cases:

• Pre-loading data into database.
• Custom startup logic.