spring-boot 自定義解析器實現參數綁定

背景

在使用spring-boot進行的web開發中，會碰到須要爲Controller實現自定義的參數裝配，好比說咱們在Controller層中定義的方法：其中的TUserEntity每每是咱們從Request中根據token解析的，那本文介紹的就是如何實現參數正確匹配。

@RequestMapping("/hello")

@ResponseBody

public Object test(TUserEntity entity) {

    // to do 
    return entity;
}

TUserEntity

public classTUserEntity {

private int id;

private String name;

// getter setter

}

Application 入口

@SpringBootApplication
@ComponentScan(basePackageClasses = Application.class)
public class Application {

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

在spring boot中實現攔截器功能

@Component
public class MyInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o) throws Exception {
        //實際狀況多是從request中得到token，繼而查找得到用戶實體
        TUserEntity entity = new TUserEntity();
        entity.setId(30);
        entity.setName("curry");
        httpServletRequest.setAttribute("tUserEntity", entity);
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) throws Exception {

    }
}

自定義參數解析器

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

    @Override
    public Object resolveArgument(MethodParameter methodParameter, ModelAndViewContainer modelAndViewContainer, NativeWebRequest nativeWebRequest, WebDataBinderFactory webDataBinderFactory) throws Exception {

        return nativeWebRequest.getAttribute("tUserEntity", 0);
    }
}

以上基本就實現了功能，以後訪問http://localhost:8080/hello能夠獲得response:
{"id":30,"name":"curry"}
哈哈 我就是庫密