2 Common Spring Boot tasks

 

This chapter covers

  • Managing configurations in a Spring Boot application
  • Creating custom configurations with @ConfigurationProperties
  • Exploring the CommandLineRunner interface to execute initialization code
  • Understanding Spring Boot default logging and configuring Log4j2 logging
  • Validating user data in a Spring Boot application using Bean Validation

By this point, we’ve learned a bit about what Spring Boot is and its purpose of improving the application development experience by abstracting specific low-level configurations. In this chapter, you’ll extend this understanding further by learning a few core concepts, such as how to manage application configuration and create a custom configuration for your application. You’ll also use Spring Boot to perform several commonly used tasks that you’ll frequently perform while developing Spring Boot applications.

2.1 Managing configurations

2.1.1 Using the SpringApplication class

2.1.2 Using @PropertySource

2.1.3 Config data file

2.1.4 OS environment variable

2.2 Creating custom properties with @ConfigurationProperties

2.2.1 Technique: Defining custom properties with @ConfigurationProperties in a Spring Boot application

2.3 Executing code on Spring Boot application startup

2.3.1 Technique: Using CommandLineRunner to execute code at Spring Boot application startup

2.4 Customizing logging in a Spring Boot application

2.4.1 Technique: Understanding and customizing default Spring Boot logging in a Spring Boot application

2.4.2 Technique: Using Log4j2 to configure logging in a Spring Boot application

2.5 Validate user data using Bean Validation

2.5.1 Technique: Using built-in Bean Validation annotations to validate business entity in a Spring Boot application

2.5.2 Technique: Defining and using custom Bean Validation annotation to validate a POJO in a Spring Boot application