org.springframework.http.server.ServletServerHttpResponse#flush ( )源码实例Demo

@Override
public void handleReturnValue(Object returnValue, MethodParameter returnType,
		ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {

	mavContainer.setRequestHandled(true);
	if (returnValue == null) {
		return;
	}

	ServletServerHttpRequest inputMessage = createInputMessage(webRequest);
	ServletServerHttpResponse outputMessage = createOutputMessage(webRequest);

	Assert.isInstanceOf(HttpEntity.class, returnValue);
	HttpEntity<?> responseEntity = (HttpEntity<?>) returnValue;

	HttpHeaders entityHeaders = responseEntity.getHeaders();
	if (!entityHeaders.isEmpty()) {
		outputMessage.getHeaders().putAll(entityHeaders);
	}

	Object body = responseEntity.getBody();
	if (responseEntity instanceof ResponseEntity) {
		outputMessage.setStatusCode(((ResponseEntity<?>) responseEntity).getStatusCode());
		if (HttpMethod.GET == inputMessage.getMethod() && isResourceNotModified(inputMessage, outputMessage)) {
			outputMessage.setStatusCode(HttpStatus.NOT_MODIFIED);
			// Ensure headers are flushed, no body should be written.
			outputMessage.flush();
			// Skip call to converters, as they may update the body.
			return;
		}
	}

	// Try even with null body. ResponseBodyAdvice could get involved.
	writeWithMessageConverters(body, returnType, inputMessage, outputMessage);

	// Ensure headers are flushed even if no body was written.
	outputMessage.flush();
}
 

@Override
public void handleReturnValue(@Nullable Object returnValue, MethodParameter returnType,
		ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {

	mavContainer.setRequestHandled(true);
	if (returnValue == null) {
		return;
	}

	ServletServerHttpRequest inputMessage = createInputMessage(webRequest);
	ServletServerHttpResponse outputMessage = createOutputMessage(webRequest);

	Assert.isInstanceOf(HttpEntity.class, returnValue);
	HttpEntity<?> responseEntity = (HttpEntity<?>) returnValue;

	HttpHeaders outputHeaders = outputMessage.getHeaders();
	HttpHeaders entityHeaders = responseEntity.getHeaders();
	if (!entityHeaders.isEmpty()) {
		entityHeaders.forEach((key, value) -> {
			if (HttpHeaders.VARY.equals(key) && outputHeaders.containsKey(HttpHeaders.VARY)) {
				List<String> values = getVaryRequestHeadersToAdd(outputHeaders, entityHeaders);
				if (!values.isEmpty()) {
					outputHeaders.setVary(values);
				}
			}
			else {
				outputHeaders.put(key, value);
			}
		});
	}

	if (responseEntity instanceof ResponseEntity) {
		int returnStatus = ((ResponseEntity<?>) responseEntity).getStatusCodeValue();
		outputMessage.getServletResponse().setStatus(returnStatus);
		if (returnStatus == 200) {
			if (SAFE_METHODS.contains(inputMessage.getMethod())
					&& isResourceNotModified(inputMessage, outputMessage)) {
				// Ensure headers are flushed, no body should be written.
				outputMessage.flush();
				ShallowEtagHeaderFilter.disableContentCaching(inputMessage.getServletRequest());
				// Skip call to converters, as they may update the body.
				return;
			}
		}
		else if (returnStatus / 100 == 3) {
			String location = outputHeaders.getFirst("location");
			if (location != null) {
				saveFlashAttributes(mavContainer, webRequest, location);
			}
		}
	}

	// Try even with null body. ResponseBodyAdvice could get involved.
	writeWithMessageConverters(responseEntity.getBody(), returnType, inputMessage, outputMessage);

	// Ensure headers are flushed even if no body was written.
	outputMessage.flush();
}
 

@Override
public void handleReturnValue(@Nullable Object returnValue, MethodParameter returnType,
		ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {

	mavContainer.setRequestHandled(true);
	if (returnValue == null) {
		return;
	}

	ServletServerHttpRequest inputMessage = createInputMessage(webRequest);
	ServletServerHttpResponse outputMessage = createOutputMessage(webRequest);

	Assert.isInstanceOf(HttpEntity.class, returnValue);
	HttpEntity<?> responseEntity = (HttpEntity<?>) returnValue;

	HttpHeaders outputHeaders = outputMessage.getHeaders();
	HttpHeaders entityHeaders = responseEntity.getHeaders();
	if (!entityHeaders.isEmpty()) {
		entityHeaders.forEach((key, value) -> {
			if (HttpHeaders.VARY.equals(key) && outputHeaders.containsKey(HttpHeaders.VARY)) {
				List<String> values = getVaryRequestHeadersToAdd(outputHeaders, entityHeaders);
				if (!values.isEmpty()) {
					outputHeaders.setVary(values);
				}
			}
			else {
				outputHeaders.put(key, value);
			}
		});
	}

	if (responseEntity instanceof ResponseEntity) {
		int returnStatus = ((ResponseEntity<?>) responseEntity).getStatusCodeValue();
		outputMessage.getServletResponse().setStatus(returnStatus);
		if (returnStatus == 200) {
			if (SAFE_METHODS.contains(inputMessage.getMethod())
					&& isResourceNotModified(inputMessage, outputMessage)) {
				// Ensure headers are flushed, no body should be written.
				outputMessage.flush();
				// Skip call to converters, as they may update the body.
				return;
			}
		}
		else if (returnStatus / 100 == 3) {
			String location = outputHeaders.getFirst("location");
			if (location != null) {
				saveFlashAttributes(mavContainer, webRequest, location);
			}
		}
	}

	// Try even with null body. ResponseBodyAdvice could get involved.
	writeWithMessageConverters(responseEntity.getBody(), returnType, inputMessage, outputMessage);

	// Ensure headers are flushed even if no body was written.
	outputMessage.flush();
}
 

@Override
public void handleReturnValue(Object returnValue, MethodParameter returnType,
		ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {

	mavContainer.setRequestHandled(true);
	if (returnValue == null) {
		return;
	}

	ServletServerHttpRequest inputMessage = createInputMessage(webRequest);
	ServletServerHttpResponse outputMessage = createOutputMessage(webRequest);

	Assert.isInstanceOf(HttpEntity.class, returnValue);
	HttpEntity<?> responseEntity = (HttpEntity<?>) returnValue;

	HttpHeaders outputHeaders = outputMessage.getHeaders();
	HttpHeaders entityHeaders = responseEntity.getHeaders();
	if (!entityHeaders.isEmpty()) {
		for (Map.Entry<String, List<String>> entry : entityHeaders.entrySet()) {
			if (HttpHeaders.VARY.equals(entry.getKey()) && outputHeaders.containsKey(HttpHeaders.VARY)) {
				List<String> values = getVaryRequestHeadersToAdd(outputHeaders, entityHeaders);
				if (!values.isEmpty()) {
					outputHeaders.setVary(values);
				}
			}
			else {
				outputHeaders.put(entry.getKey(), entry.getValue());
			}
		}
	}

	if (responseEntity instanceof ResponseEntity) {
		int returnStatus = ((ResponseEntity<?>) responseEntity).getStatusCodeValue();
		outputMessage.getServletResponse().setStatus(returnStatus);
		if (returnStatus == 200) {
			if (isResourceNotModified(inputMessage, outputMessage)) {
				// Ensure headers are flushed, no body should be written.
				outputMessage.flush();
				// Skip call to converters, as they may update the body.
				return;
			}
		}
	}

	// Try even with null body. ResponseBodyAdvice could get involved.
	writeWithMessageConverters(responseEntity.getBody(), returnType, inputMessage, outputMessage);

	// Ensure headers are flushed even if no body was written.
	outputMessage.flush();
}