Spring自定义参数解析器

结合redis编写User自定义参数解析器UserArgumentResolver

 import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletRequest;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.core.MethodParameter;
 import org.springframework.stereotype.Service;
 import org.springframework.web.bind.support.WebDataBinderFactory;
 import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
 import org.springframework.web.method.support.ModelAndViewContainer;
 import cn.xingaohbd.seckil.model.User;
 import cn.xingaohbd.seckil.service.UserService;

 @Service
 public class UserArgumentResolver implements HandlerMethodArgumentResolver {

     @Autowired
     public UserService userService;

     public String getParameterCokies(HttpServletRequest request,String tokenName){
         Cookie[] cookies = request.getCookies();
         for (Cookie ck : cookies) {
             if(ck.getName().equals(tokenName)){
                 return ck.getValue();
             }
         }
         return null;
     }

     @Override
     public boolean supportsParameter(MethodParameter methodParameter) {
         Class<?> p_class = methodParameter.getParameterType();
         return p_class == User.class;
     }

     @Override
     public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
             NativeWebRequest nativeWebRequest, WebDataBinderFactory binderFactory) throws Exception {
         HttpServletRequest request = nativeWebRequest.getNativeRequest(HttpServletRequest.class);
         String requestParameter_token = request.getParameter("token");
         String cokies_token = getParameterCokies(request, "token");
         if(requestParameter_token == null && cokies_token == null){
             return null;
         }
         return userService.getUserFromRedisByToken(requestParameter_token != null ? requestParameter_token : cokies_token);
     }

 }

UserService

@Service
@Transactional
public class UserServiceImpl implements UserService {
    @Autowired
    private UserRedis userRedis;

    @Override
    public Object getUserFromRedisByToken(String token) {
        return userRedis.get(token);
    }
}

在WebConfig中注册自定义参数解析器UserArgumentResolver

import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.util.ResourceUtils;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;

@Configuration
public class WebConfig extends WebMvcConfigurationSupport{

    @Autowired
    UserArgumentResolver userArgumentResolver;

    @Override
    protected void addArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers) {
        argumentResolvers.add(userArgumentResolver);
    }

    public void addResourceHandlers(ResourceHandlerRegistry registry){
        registry.addResourceHandler("/**").addResourceLocations(ResourceUtils.CLASSPATH_URL_PREFIX+"/static/");
        super.addResourceHandlers(registry);
    }

}