Auto-configuration is non-invasive. At any point, you can start to define your own configuration to replace specific parts of the auto-configuration. For example, if you add your own DataSource bean, the default embedded database support backs away.

If you need to find out what auto-configuration is currently being applied, and why, start your application with the --debug switch. Doing so enables debug logs for a selection of core loggers and logs a conditions report to the console.

If you find that specific auto-configuration classes that you do not want are being applied, you can use the exclude attribute of @SpringBootApplication to disable them, as shown in the following example:

import org.springframework.boot.autoconfigure.*;
import org.springframework.boot.autoconfigure.jdbc.*;

@SpringBootApplication(exclude={DataSourceAutoConfiguration.class})
public class MyApplication {
}

If the class is not on the classpath, you can use the excludeName attribute of the annotation and specify the fully qualified name instead. If you prefer to use @EnableAutoConfiguration rather than @SpringBootApplication, exclude and excludeName are also available. Finally, you can also control the list of auto-configuration classes to exclude by using the spring.autoconfigure.exclude property.

	Tip
	You can define exclusions both at the annotation level and by using the property.

	Note
	Even though auto-configuration classes are public, the only aspect of the class that is considered public API is the name of the class which can be used for disabling the auto-configuration. The actual contents of those classes, such as nested configuration classes or bean methods are for internal use only and we do not recommend using those directly.