找到请求类型 [java.lang.Long] 的 HttpMessageConverter

Question

SpringBoot

RestTemplate 转换器添加 FormHttpMessageConverter.java 和 StringHttpMessageConverter 以及 ResourceHttpMessageConverter 和 ByteArrayHttpMessageConverter，

Http client Long in params: parts.add("time", time);


org.springframework.http.converter.HttpMessageNotWritableException: Could not write request: no suitable HttpMessageConverter found for request type [java.lang.Long]
    at org.springframework.http.converter.FormHttpMessageConverter.writePart(FormHttpMessageConverter.java:422)
    at org.springframework.http.converter.FormHttpMessageConverter.writeParts(FormHttpMessageConverter.java:393)
    at org.springframework.http.converter.FormHttpMessageConverter.writeMultipart(FormHttpMessageConverter.java:373)
    at org.springframework.http.converter.FormHttpMessageConverter.write(FormHttpMessageConverter.java:277)
    at org.springframework.http.converter.FormHttpMessageConverter.write(FormHttpMessageConverter.java:95)
    at org.springframework.web.client.RestTemplate$HttpEntityRequestCallback.doWithRequest(RestTemplate.java:948)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:733)
    at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:670)
    at org.springframework.web.client.RestTemplate.postForObject(RestTemplate.java:414)

HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.MULTIPART_FORM_DATA);
headers.setAccept(Collections.singletonList(MediaType.APPLICATION_FORM_URLENCODED));
headers.setAcceptCharset(Collections.singletonList(CharsetUtil.CHARSET_UTF_8));
FileSystemResource zipFile = new FileSystemResource(new File(file.getAbsolutePath()));
MultiValueMap<String, Object> parts = new LinkedMultiValueMap<>();
Long time = System.currentTimeMillis();
parts.add("time", time);
parts.add("md5", SecureUtil.md5(time + "234234").toUpperCase());
parts.add("file", zipFile);
HttpEntity<MultiValueMap<String, Object>> requestEntity = new HttpEntity<>(parts, headers);

什么HttpMessageConverter可以支持Long？

Answer 1

默认情况下，以下消息转换器在 spring 中启用：

ByteArrayHttpMessageConverter – converts byte arrays
StringHttpMessageConverter – converts Strings
ResourceHttpMessageConverter – converts org.springframework.core.io.Resource for any type of octet stream
SourceHttpMessageConverter – converts javax.xml.transform.Source
FormHttpMessageConverter – converts form data to/from a MultiValueMap<String, String>.
Jaxb2RootElementHttpMessageConverter – converts Java objects to/from XML (added only if JAXB2 is present on the classpath)
MappingJackson2HttpMessageConverter – converts JSON (added only if Jackson 2 is present on the classpath)
MappingJacksonHttpMessageConverter – converts JSON (added only if Jackson is present on the classpath)
AtomFeedHttpMessageConverter – converts Atom feeds (added only if Rome is present on the classpath)
RssChannelHttpMessageConverter – converts RSS feeds (added only if Rome is present on the classpath)

收到新请求时，Spring 将使用“接受”header 来确定响应with.In 您的情况所需的媒体类型，FormHttpMessageConverter是spring中默认选择的转换器，因为您已经指定内容type.When写入多部分数据，此转换器使用其他HttpMessageConverters写入相应的MIME部分。FormHttpMessageConverter class 找不到 Long 类型的消息转换器。因此，您可以尝试将 Long 转换为字符串并将其分配给像 :

这样的部分

                Long time = System.currentTimeMillis();
                parts.add("time", String.valueOf(time));
                parts.add("md5", SecureUtil.md5(time + "234234").toUpperCase());
                parts.add("file", zipFile);
                HttpEntity<MultiValueMap<String, Object>> requestEntity = new HttpEntity<>(parts, headers);

Doc

找到请求类型 [java.lang.Long] 的 HttpMessageConverter

HttpMessageConverter found for request type [java.lang.Long]

java

httpclient

resttemplate

spring-boot