6.4 Summary

• We can annotate Spring beans with @ConfigurationProperties to enable injection of values from one of several property sources.
• Configuration properties can be set in command-line arguments, environment variables, JVM system properties, properties files, or YAML files, among other options.
• Use configuration properties to override autoconfiguration settings, including the ability to specify a data source URL and logging levels.
• Spring profiles can be used with property sources to conditionally set configuration properties based on the active profile(s).