Spring 으로 encoder 예제따라하다가 계속 실패하네요ㅠㅠ

[Jeong-ki-hun]

org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: @configuration class 'AppConfig' contains overloaded @bean methods with name 'encoder'. Use unique method names for separate bean definitions (with individual conditions etc) or switch '@Configuration.enforceUniqueMethods' to 'false'.
Offending resource: class path resource [com/example/springioc/AppConfig.class]

에러 메세지에는 이렇게 나오는데 구글링해도 답이 안나오네요ㅠㅠ