ResolvableType.getNested typeProvider was missing

[TAKETODAY]

This causes JacksonJsonHttpMessageConverter.read() 's contextClass to resolve to null

Determine why this fails with JacksonJsonHttpMessageConverter but passes with MappingJackson2HttpMessageConverter

Because the MappingJackson2HttpMessageConverter is a GenericHttpMessageConverter that explicitly provides the contextClass during reading, whereas the JacksonJsonHttpMessageConverter obtains it through (ResolvableType.getSource() as MethodParameter).getContainingClass.

spring-framework/spring-web/src/main/java/org/springframework/http/converter/GenericHttpMessageConverter.java

Lines 69 to 71 in 253eb28

	T read(Type type, @Nullable Class<?> contextClass, HttpInputMessage inputMessage)
	throws IOException, HttpMessageNotReadableException;

but type.getSource() is not instanceof MethodParameter

spring-framework/spring-web/src/main/java/org/springframework/http/converter/AbstractJacksonHttpMessageConverter.java

Lines 311 to 320 in 253eb28

	@Override
	public Object read(ResolvableType type, HttpInputMessage inputMessage, @Nullable Map<String, Object> hints)
	throws IOException, HttpMessageNotReadableException {
	Class<?> contextClass = (type.getSource() instanceof MethodParameter parameter ? parameter.getContainingClass() : null);
	JavaType javaType = getJavaType(type.getType(), contextClass);
	return readJavaType(javaType, inputMessage, hints);
	}

spring-framework/spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/HttpEntityMethodProcessorTests.java

Lines 154 to 176 in 253eb28

	@Test
	@Disabled("Determine why this fails with JacksonJsonHttpMessageConverter but passes with MappingJackson2HttpMessageConverter")
	void resolveArgumentTypeVariable() throws Exception {
	Method method = MySimpleParameterizedController.class.getMethod("handleDto", HttpEntity.class);
	HandlerMethod handlerMethod = new HandlerMethod(new MySimpleParameterizedController(), method);
	MethodParameter methodParam = handlerMethod.getMethodParameters()[0];
	String content = "{\"name\" : \"Jad\"}";
	this.servletRequest.setContent(content.getBytes(StandardCharsets.UTF_8));
	this.servletRequest.setContentType(MediaType.APPLICATION_JSON_VALUE);
	List<HttpMessageConverter<?>> converters = new ArrayList<>();
	converters.add(new JacksonJsonHttpMessageConverter());
	HttpEntityMethodProcessor processor = new HttpEntityMethodProcessor(converters);
	@SuppressWarnings("unchecked")
	HttpEntity<SimpleBean> result = (HttpEntity<SimpleBean>)
	processor.resolveArgument(methodParam, mavContainer, webRequest, binderFactory);
	assertThat(result).isNotNull();
	assertThat(result.getBody().getName()).isEqualTo("Jad");
	}

[bclozel]

@TAKETODAY please sign your commit; no need to close/create a new PR, you can do this with:

git amend -s
git push --force

See this blog post for more information

[sdeleuze]

Thanks for this PR, we are going to fix this but I tend to think it will be better (less risk of regression due to the changes on utility methods, more robust) to handle that using SmartHttpMessageConverter hints. As a consequence, I will decline this PR and create a related issue that I will tentativaly fix for 7.0.3.

[TAKETODAY]

Thanks for this PR, we are going to fix this but I tend to think it will be better (less risk of regression due to the changes on utility methods, more robust) to handle that using SmartHttpMessageConverter hints. As a consequence, I will decline this PR and create a related issue that I will tentativaly fix for 7.0.3.

OK，Thank you for your reply.