매개변수 해석기HandlerMethodArgumentResolver

HandlerMethodArgumentResolver 사용

1. 솔리드 클래스 Person 정의

@Data
public class Person {
    private String firstName;
    private String lastName="notVa";

    public Person(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }
}

2. Controller를 사용하여 이 Person 가져오기

// firstName lastName
@Controller
public class DemoHandlerMethodArgumentResolverController {

    @RequestMapping(value = "/demoAddPerson")
    @ResponseBody
    public String addPerson(Person person) {
        System.out.println(person.toString());
        return person.toString();
    }
}

3. 매개 변수의 해석 과정을 스스로 정의하고 해석기를 만들 수 있다

@Component
// HandlerMethodArgumentResolver 
public class PersonArgumentResolver implements HandlerMethodArgumentResolver {
    @Override
    public boolean supportsParameter(MethodParameter methodParameter) {
        return methodParameter.getParameterType().equals(Person.class);
    }

    @Override
    public Object resolveArgument(MethodParameter methodParameter, ModelAndViewContainer modelAndViewContainer, NativeWebRequest nativeWebRequest, WebDataBinderFactory webDataBinderFactory) throws Exception {
        HttpServletRequest request = nativeWebRequest.getNativeRequest(HttpServletRequest.class);
        String firstName = request.getParameter("firstName");
        String lastName = request.getParameter("lastName");
        return new Person("new"+firstName,"new"+lastName);
    }
}

// 
public interface HandlerMethodArgumentResolver {
    // ， true ， resolveArgument。
    boolean supportsParameter(MethodParameter parameter);
    // ， Object controller 。
    Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
            NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception;

}

4. 이 해상도 등록

// WebMvcConfigurationSupport ， 
@Configuration
public class ConfigArgumentResolver extends WebMvcConfigurationSupport {
    @Autowired
    private PersonArgumentResolver personArgumentResolver;

    @Override
    public void addArgumentResolvers(List argumentResolvers) {
        argumentResolvers.add(personArgumentResolver);
    }
}

5. 효과 테스트

다중 Person

1. 메모 추가

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.PARAMETER)
public @interface MultiPerson {
    String value();
}

2. 파서

@Component
public class MultiPersonArgumentResolver implements HandlerMethodArgumentResolver {
    @Override
    public boolean supportsParameter(MethodParameter methodParameter) {
        return methodParameter.hasParameterAnnotation(MultiPerson.class) && methodParameter.getParameterType().equals(Person.class);
    }

    @Override
    public Object resolveArgument(MethodParameter methodParameter, ModelAndViewContainer modelAndViewContainer, NativeWebRequest nativeWebRequest, WebDataBinderFactory webDataBinderFactory) throws Exception {
        HttpServletRequest request = nativeWebRequest.getNativeRequest(HttpServletRequest.class);
        MultiPerson multiPerson = methodParameter.getParameterAnnotation(MultiPerson.class);
        String firstName = multiPerson.value()+"."+ request.getParameter("firstName");
        String lastName = multiPerson.value()+"."+ request.getParameter("lastName");
        return new Person(firstName,lastName);
    }
}

3. 등록

@Configuration
public class ConfigArgumentResolver extends WebMvcConfigurationSupport {
    @Autowired
    private PersonArgumentResolver personArgumentResolver;

    @Autowired
    private MultiPersonArgumentResolver multiPersonArgumentResolver;

    @Override
    public void addArgumentResolvers(List argumentResolvers) {
        //argumentResolvers.add(personArgumentResolver);
        argumentResolvers.add(multiPersonArgumentResolver);

    }
}

4.Controller

@RequestMapping(value = "/demoAddMultiPerson")
    @ResponseBody
    public String addMultiPerson(@MultiPerson("person1") Person person1,@MultiPerson("person2")Person person2) {
        System.out.println(person1.toString());
        System.out.println(person2.toString());
        return person1.toString()+" --- "+ person2.toString();
    }

5. 효과 테스트