How do you create a custom Auto-Configuration in Spring Boot? स्प्रिंग बूट में कस्टम ऑटो-कॉन्फिगरेशन कैसे बनाएं?

A custom auto-configuration is a @Configuration class registered so Spring Boot picks it up automatically when the library is on the classpath.

It is typically guarded with conditional annotations like @ConditionalOnClass and @ConditionalOnProperty so it only activates when relevant dependencies or properties are present, and its beans are usually paired with @ConditionalOnMissingBean so users can override them. The class is registered by listing its fully qualified name in META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports.

@Configuration
@ConditionalOnClass(MyService.class)
public class MyServiceAutoConfiguration {
    @Bean
    @ConditionalOnMissingBean
    public MyService myService() {
        return new MyServiceImpl();
    }
}