Java 我总是收到一封“信”；“不支持的媒体类型”；使用RestTemplate时出错

所以我在休息方面有困难（我是初学者）。我想把一个多部分表单放到某个URL上。我通过Jersey在web上找到的一个示例实现了这一点，不幸的是，在我的项目中，我应该使用spring framework web客户端。下面是我的工作代码

// setup properties
String publishUrl = "http://localhost:8080/url/to/rest/api";
File schemaFile = new File("myfile.xml");
String catalogName = "myFileName";

FileInputStream inputStream = new FileInputStream(schemaFile);
String jndiName = "myJNDI";
boolean overwrite = true;
boolean enableXmla = true;

//set up multi part form. 
FormDataMultiPart part = new FormDataMultiPart()
        .field("uploadAnalysis", inputStream, MediaType.MULTIPART_FORM_DATA_TYPE)
        .field("catalogName", catalogName, MediaType.MULTIPART_FORM_DATA_TYPE)
        .field("Datasource", jndiName, MediaType.MULTIPART_FORM_DATA_TYPE)
        .field("overwrite", overwrite ? "true" : "false", MediaType.MULTIPART_FORM_DATA_TYPE)
        .field("xmlaEnabledFlag", enableXmla ? "true" : "false", MediaType.MULTIPART_FORM_DATA_TYPE)
        .field("parameters", "Datasource=" + jndiName, MediaType.MULTIPART_FORM_DATA_TYPE);

// If the import service needs the file name do the following.
part.getField("uploadAnalysis").setContentDisposition(FormDataContentDisposition.name("uploadAnalysis").fileName(schemaFile.getName()).build());

//set up client and create web resource
Client client = Client.create();
client.addFilter(new HTTPBasicAuthFilter("Admin", "password"));

WebResource resource = client.resource(publishUrl);
ClientResponse response = resource.type(MediaType.MULTIPART_FORM_DATA_TYPE).put(ClientResponse.class, part);

System.out.println(response.getStatus());

这个很好用。因此，现在我已经尝试将其转录到SpringWeb客户机上。以下是我当前的代码

//setup properties
String publishUrl = "http://localhost:8080/url/to/rest/api";
File schemaFile = new File("myFile.xml");
String catalogName = "myFileName";
String jndiName = "myJNDI";
boolean overwrite = true;
boolean enableXmla = true;

//setup form
MultiValueMap<String, Object> form = new LinkedMultiValueMap<String, Object>();
form.add("uploadAnalysis", new FileSystemResource(schemaFile));
form.add("catalogName", catalogName);
form.add("Datasource", jndiName);
form.add("overwrite", overwrite ? "true" : "false");
form.add("xmlaEnabledFlag", enableXmla ? "true" : "false");
form.add("parameters", "Datasource=" + jndiName);

//Set up credentials
CredentialsProvider credsProvider = new BasicCredentialsProvider();
credsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials("Admin", "password"));

//set up http client
CloseableHttpClient httpclient = HttpClients.custom().setDefaultCredentialsProvider(credsProvider).build();

//create client request factory using httpcient
HttpComponentsClientHttpRequestFactory fact = new HttpComponentsClientHttpRequestFactory(httpclient);

//create rest template
RestTemplate rt = new RestTemplate(fact);

//create http headers
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.MULTIPART_FORM_DATA);

//use put method. 
rt.put(publishUrl, headers, form);

我对此有点困惑，因为在Jersey我将MediaType设置为“MULTIPART\u FORM\u DATA\u TYPE”，而在Spring我将其设置为“MULTIPART\u FORM\u DATA”，所以我不确定为什么这会给我一个不受支持的媒体类型。任何想法都会有帮助

编辑

因此，我将代码更改为不使用.put（）方法，因为我使用了错误的方法，更改如下所示

    HttpEntity<MultiValueMap<String, Object>> entity = new HttpEntity<MultiValueMap<String, Object>>(form, headers);

    ResponseEntity<String> response = rt.exchange(publishUrl, HttpMethod.PUT, entity, String.class);

---

奇怪的是，文件被上传到服务器，但是我没有从服务器得到任何响应。是否需要设置某种类型的标题才能获得响应或其他什么？当使用Jersey时，我每次都会收到一个响应，所以我想知道Jersey中是否有我不知道的预配置内容。

您使用的

restemplate#put（…）

不正确。第三个参数是URI变量的映射。相反，请使用其中一种方法，在该方法中可以传递带有适当标题的

HttpEntity

。

我将此put方法更改为

HttpEntity entity=new-HttpEntity（表单，标题）；ResponseEntity response=rt.exchange（publishUrl、HttpMethod.PUT、entity、String.class）但我现在收到一条消息说localhost:8080未能响应。@seap这似乎表明您的服务器已关闭。当然不是，这就是为什么我有点困惑的原因，Jersey上传文件很好。@seap您是说您遇到了网络异常吗？您可以发布堆栈跟踪吗？
org.springframework.web.client.ResourceAccessException:PUT请求时发生I/O错误“http://localhost:8080/url/to/rest/api“：localhost:8080响应失败；嵌套的异常是org.apache.http.NoHttpResponseException:localhost:8080未能在org.springframework.web.client.restemplate.doExecute（restemplate.java:543）org.springframework.web.client.restemplate.execute（restemplate.java:489）org.springframework.web.client.restemplate.exchange（restemplate.java:431）响应。
    HttpEntity<MultiValueMap<String, Object>> entity = new HttpEntity<MultiValueMap<String, Object>>(form, headers);

    ResponseEntity<String> response = rt.exchange(publishUrl, HttpMethod.PUT, entity, String.class);

org.springframework.web.client.ResourceAccessException: I/O error on PUT request for "http://localhost:8080/url/to/rest/api":localhost:8080 failed to respond; nested exception is org.apache.http.NoHttpResponseException: localhost:8080 failed to respond
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:543)
at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:489)
at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:431)