[spring] method argument resolver

[heowc]

• spring boot 2.1.1.RELEASE 기준
• spring-boot-starter-web 의존성 추가

@SpringBootApplication
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Bean
    public ApplicationRunner runner(RequestMappingHandlerAdapter adapter) {
        return args -> {
            adapter.getArgumentResolvers().stream().map(HandlerMethodArgumentResolver::toString).forEach(System.out::println);
        };
    }
}

org.springframework.web.method.annotation.RequestParamMethodArgumentResolver@5b69fd74
org.springframework.web.method.annotation.RequestParamMapMethodArgumentResolver@f325091
org.springframework.web.servlet.mvc.method.annotation.PathVariableMethodArgumentResolver@437e951d
org.springframework.web.servlet.mvc.method.annotation.PathVariableMapMethodArgumentResolver@77b325b3
org.springframework.web.servlet.mvc.method.annotation.MatrixVariableMethodArgumentResolver@63a5e46c
org.springframework.web.servlet.mvc.method.annotation.MatrixVariableMapMethodArgumentResolver@7e8e8651
org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor@49ef32e0
org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor@271f18d3
org.springframework.web.servlet.mvc.method.annotation.RequestPartMethodArgumentResolver@6bd51ed8
org.springframework.web.method.annotation.RequestHeaderMethodArgumentResolver@61e3a1fd
org.springframework.web.method.annotation.RequestHeaderMapMethodArgumentResolver@51abf713
org.springframework.web.servlet.mvc.method.annotation.ServletCookieValueMethodArgumentResolver@eadb475
org.springframework.web.method.annotation.ExpressionValueMethodArgumentResolver@4d4d48a6
org.springframework.web.servlet.mvc.method.annotation.SessionAttributeMethodArgumentResolver@315df4bb
org.springframework.web.servlet.mvc.method.annotation.RequestAttributeMethodArgumentResolver@3fc08eec
org.springframework.web.servlet.mvc.method.annotation.ServletRequestMethodArgumentResolver@5cad8b7d
org.springframework.web.servlet.mvc.method.annotation.ServletResponseMethodArgumentResolver@7b02e036
org.springframework.web.servlet.mvc.method.annotation.HttpEntityMethodProcessor@25243bc1
org.springframework.web.servlet.mvc.method.annotation.RedirectAttributesMethodArgumentResolver@1e287667
org.springframework.web.method.annotation.ModelMethodProcessor@2e6ee0bc
org.springframework.web.method.annotation.MapMethodProcessor@4201a617
org.springframework.web.method.annotation.ErrorsMethodArgumentResolver@467f77a5
org.springframework.web.method.annotation.SessionStatusMethodArgumentResolver@1bb9aa43
org.springframework.web.servlet.mvc.method.annotation.UriComponentsBuilderMethodArgumentResolver@420bc288
org.springframework.web.method.annotation.RequestParamMethodArgumentResolver@df5f5c0
org.springframework.web.servlet.mvc.method.annotation.ServletModelAttributeMethodProcessor@308a6984

[heowc]

DispatcherServlet ↓ RequestMappingHandlerAdapter ↓ ServletInvocableHandlerMethod ↓ HandlerMethodArgumentResolverComposite ↓ xxxxHandlerMethodArgumentResolver

[heowc]

• Map과 Map이 아닌 것으로 분리되어 리졸버 작성
• @RequestParam으로 전달할 수 있는 데이터는 생략 가능

코드

@RestController
public class ExampleController {

    @GetMapping("/")
    public String get(String message) {
        return message;
    }
}

결과

[GET] http://localhost:8080/?message=test

test

• @RequestPart 라는 녀석이 있다.
  • 특정 컨텐트 타입을 복잡하게 전달받을 때 활용