1.异常
org.springframework.http.converter.HttpMessageNotReadableException: Required request body is missing
2.问题复现：
@RequestMapping(value = "/somewhere", method = POST)
public SomeResponse someHandler(@RequestBody XXXDTO xxxDTO) { ... }
当入参DTO对象为空时，@RequestBody对应http请求body,当请求body为空时，异常！org.springframework.http.converter.HttpMessageNotReadableException: Required request body is missing: public com.rpc.common.Result<com.rpc.common.dto.PageDto<com.order.dto.OrderListDTO>> com.gateway.controller.OrderController.listOrder(com.mljr.lease.order.dto.ListOrderPageDTO) at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.readWithMessageConverters(RequestResponseBodyMethodProcessor.java:154) at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.resolveArgument(RequestResponseBodyMethodProcessor.java:128) at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:121) at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:158) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:128) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) at javax.servlet.http.HttpServlet.service(HttpServlet.java:661) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.springframework.boot.web.filter.ApplicationContextHeaderFilter.doFilterInternal(ApplicationContextHeaderFilter.java:55) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
1 @Override
2 protected <T> Object readWithMessageConverters(NativeWebRequest webRequest, MethodParameter parameter,
3 Type paramType) throws IOException, HttpMediaTypeNotSupportedException, HttpMessageNotReadableException {
4
5 HttpServletRequest servletRequest = webRequest.getNativeRequest(HttpServletRequest.class);
6 ServletServerHttpRequest inputMessage = new ServletServerHttpRequest(servletRequest);
7
8 Object arg = readWithMessageConverters(inputMessage, parameter, paramType);
9 if (arg == null) {
10 if (checkRequired(parameter)) {
11 throw new HttpMessageNotReadableException("Required request body is missing: " +
12 parameter.getMethod().toGenericString());
13 }
14 }
15 return arg;
16 }
17
18 protected boolean checkRequired(MethodParameter parameter) {
19 return (parameter.getParameterAnnotation(RequestBody.class).required() && !parameter.isOptional());
20 }
看上图，最终是RequestBody注解的required属性。!parameter.isOptional()代表是否支持null,如果参数类型支持null,则是false,最终不用校验required.
1 public @interface RequestBody {
2
3 /**
4 * Whether body content is required.
5 * <p>Default is {@code true}, leading to an exception thrown in case
6 * there is no body content. Switch this to {@code false} if you prefer
7 * {@code null} to be passed when the body content is {@code null}.
8 * @since 3.2
9 */
10 boolean required() default true;
11
12 }
看上图，默认是true.我们只需要@RequestBody （required=false）
3.解决方案：
1）@RequestBody （required=false）
2) 不要让DTO对象为空
时间： 2024-10-05 06:16:58