控制器判断void类型返回值

谁践踏了优雅 2023-07-13 08:08 1阅读 0赞

##### 1.返回值类型为void类型 #####

if(!returnType.getMethod().getReturnType().equals(Void.TYPE)){
               //TODO
       }

##### 2.返回值类型为ResponseEntity类型 #####

Type type = returnType.getMethod().getGenericReturnType();
                if((type instanceof ParameterizedType) && !(((ParameterizedType)type).getActualTypeArguments()[0]).equals(Void.class)){
                   //TODO
                }

##### 3.具体示例 #####

package com.yaomy.control.returnvalue.handler;
    
    import BaseResponse;
    import RouteUtils;
    import org.springframework.core.MethodParameter;
    import org.springframework.core.annotation.AnnotatedElementUtils;
    import org.springframework.web.bind.annotation.ResponseBody;
    import org.springframework.web.context.request.NativeWebRequest;
    import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
    import org.springframework.web.method.support.ModelAndViewContainer;
    
    import javax.servlet.http.HttpServletRequest;
    import java.util.LinkedHashMap;
    import java.util.Map;
    
    /**
     * @Description: 控制器返回返回值包装类,处理带@ResponseBody标识的返回值类型
     * @Version: 1.0
     */
    public class ResponseMethodReturnValueHandler implements HandlerMethodReturnValueHandler {
    
        private HandlerMethodReturnValueHandler proxyObject;
    
        public ResponseMethodReturnValueHandler(HandlerMethodReturnValueHandler proxyObject) {
            this.proxyObject = proxyObject;
        }
    
        @Override
        public boolean supportsReturnType(MethodParameter returnType) {
            return (AnnotatedElementUtils.hasAnnotation(returnType.getContainingClass(), ResponseBody.class) ||
                    returnType.hasMethodAnnotation(ResponseBody.class));
        }
    
        @Override
        public void handleReturnValue(Object returnValue, MethodParameter returnType, ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {
            //标注该请求已经在当前处理程序处理过
            mavContainer.setRequestHandled(true);
            HttpServletRequest request = webRequest.getNativeRequest(HttpServletRequest.class);
            if(RouteUtils.readRoute().contains(request.getRequestURI())){
                proxyObject.handleReturnValue(returnValue, returnType, mavContainer, webRequest);
            } else if(null != returnValue && (returnValue instanceof BaseResponse)){
                proxyObject.handleReturnValue(returnValue, returnType, mavContainer, webRequest);
            } else {
                Map<String, Object> resultMap = new LinkedHashMap<>();
                resultMap.put("status", 0);
                resultMap.put("message", "SUCCESS");
                if(!returnType.getMethod().getReturnType().equals(Void.TYPE)){
                    resultMap.put("data", returnValue);
                }
                proxyObject.handleReturnValue(resultMap, returnType, mavContainer, webRequest);
            }
        }
    
    }

示例二：

package com.yaomy.control.returnvalue.handler;
    
    import BaseResponse;
    import RouteUtils;
    import org.springframework.core.MethodParameter;
    import org.springframework.http.HttpEntity;
    import org.springframework.http.RequestEntity;
    import org.springframework.http.ResponseEntity;
    import org.springframework.web.context.request.NativeWebRequest;
    import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
    import org.springframework.web.method.support.ModelAndViewContainer;
    
    import javax.servlet.http.HttpServletRequest;
    import java.lang.reflect.ParameterizedType;
    import java.lang.reflect.Type;
    import java.util.LinkedHashMap;
    import java.util.Map;
    
    /**
     * @Description: HttpEntity返回值控制
     * @Version: 1.0
     */
    public class ResponseHttpEntityMethodReturnValueHandler implements HandlerMethodReturnValueHandler {
    
        private HandlerMethodReturnValueHandler proxyObject;
    
        public ResponseHttpEntityMethodReturnValueHandler(HandlerMethodReturnValueHandler proxyObject){
            this.proxyObject = proxyObject;
        }
        @Override
        public boolean supportsReturnType(MethodParameter returnType) {
            return (HttpEntity.class.isAssignableFrom(returnType.getParameterType()) &&
                    !RequestEntity.class.isAssignableFrom(returnType.getParameterType()));
        }
    
        @Override
        public void handleReturnValue(Object returnValue, MethodParameter returnType, ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {
            //标注该请求已经在当前处理程序处理过
            mavContainer.setRequestHandled(true);
            //获取ResponseEntity封装的真实返回值
            Object body = (null == returnValue) ? null :((ResponseEntity) returnValue).getBody();
            HttpServletRequest request = webRequest.getNativeRequest(HttpServletRequest.class);
            if(RouteUtils.readRoute().contains(request.getRequestURI())){
                proxyObject.handleReturnValue(returnValue, returnType, mavContainer, webRequest);
            } else if(null != body && (body instanceof BaseResponse)){
                proxyObject.handleReturnValue(returnValue, returnType, mavContainer, webRequest);
            } else {
                Map<String, Object> resultMap = new LinkedHashMap<>();
                resultMap.put("status", 0);
                resultMap.put("message", "SUCCESS");
                Type type = returnType.getMethod().getGenericReturnType();
                if((type instanceof ParameterizedType) && !(((ParameterizedType)type).getActualTypeArguments()[0]).equals(Void.class)){
                    resultMap.put("data", body);
                }
                proxyObject.handleReturnValue(ResponseEntity.ok(resultMap), returnType, mavContainer, webRequest);
            }
        }
    }

GitHub地址：[https://github.com/mingyang66/spring-parent/tree/master/sgrain-spring-boot-returnvalue-service/doc][https_github.com_mingyang66_spring-parent_tree_master_sgrain-spring-boot-returnvalue-service_doc]

[https_github.com_mingyang66_spring-parent_tree_master_sgrain-spring-boot-returnvalue-service_doc]: https://github.com/mingyang66/spring-parent/tree/master/sgrain-spring-boot-returnvalue-service/doc