Java JSON 字符串编码Multipart问题

Question

我正在开发一个接收 MultipartFormDataInput 对象 (org.jboss.resteasy.plugins.providers.multipart.MultipartFormDataInput) 的 REST API，它来自表单数据 Vue.js 应用程序。数据字段上有一个 json 字符串，其中包含拉丁重音字符（á、é、í、ó、ú、ñ）。当在 Java 中打印 json 数据时，我得到这个：

原始Json字符串

{
  "code": "123456789",
  "form": "test",
  "pot": "special character  ñ",
  "categoria": "acción",
  "propiedad": "algún",
  "diligencia": "ábaco",
  "actual": "grabé",
  "pais":  "Abstraído",
  "vivio_otro_pais_cual": "word without special characters... OK  1 2 3<>?!@#$%^&*()_+"
}

Json 在 Java

中收到的字符串

11:04:32,086 INFO  [stdout] (default task-1) JSON VALUES.... {
11:04:32,087 INFO  [stdout] (default task-1)   "code": "123456789",
11:04:32,087 INFO  [stdout] (default task-1)   "form": "test",
11:04:32,087 INFO  [stdout] (default task-1)   "pot": "special character  ??",
11:04:32,087 INFO  [stdout] (default task-1)   "categoria": "acci??n",
11:04:32,087 INFO  [stdout] (default task-1)   "propiedad": "alg??n",
11:04:32,087 INFO  [stdout] (default task-1)   "diligencia": "??baco",
11:04:32,087 INFO  [stdout] (default task-1)   "actual": "grab??",
11:04:32,087 INFO  [stdout] (default task-1)   "pais":  "Abstra??do",
11:04:32,087 INFO  [stdout] (default task-1)   "vivio_otro_pais_cual": "word without special characters... OK  1 2 3<>?!@#$%^&*()_+"
11:04:32,087 INFO  [stdout] (default task-1) }

11:04:32,088 INFO  [stdout] (default task-1) JSON ENCODING.... {
11:04:32,088 INFO  [stdout] (default task-1)   "code": "123456789",
11:04:32,088 INFO  [stdout] (default task-1)   "form": "test",
11:04:32,088 INFO  [stdout] (default task-1)   "pot": "special character  ??",
11:04:32,088 INFO  [stdout] (default task-1)   "categoria": "acci??n",
11:04:32,088 INFO  [stdout] (default task-1)   "propiedad": "alg??n",
11:04:32,088 INFO  [stdout] (default task-1)   "diligencia": "??baco",
11:04:32,088 INFO  [stdout] (default task-1)   "actual": "grab??",
11:04:32,088 INFO  [stdout] (default task-1)   "pais":  "Abstra??do",
11:04:32,088 INFO  [stdout] (default task-1)   "vivio_otro_pais_cual": "word without special characters... OK  1 2 3<>?!@#$%^&*()_+"
11:04:32,088 INFO  [stdout] (default task-1) }

如何接收带有拉丁特殊字符的字符串？

我的代码（终点）：

@POST
@Path("/testEncoding")
@Consumes(MediaType.MULTIPART_FORM_DATA)
public Response testEncoding(@Context HttpHeaders headers, MultipartFormDataInput  multipart){
    return interfaceOperationService.testEncoding(headers, multipart);
}

实施：

public Response testEncoding(HttpHeaders headers, MultipartFormDataInput multipart) {

    try {
                
        String dataJson = multipart.getFormDataPart("data", String.class, null);
        String valorCodificado = new String (dataJson.getBytes(StandardCharsets.US_ASCII), StandardCharsets.UTF_8);
        System.out.println("JSON VALUES.... " + dataJson);
        System.out.println("JSON ENCODING.... " + valorCodificado);
                
        StringBuilder sb = new StringBuilder();
        for (String header : headers.getRequestHeaders().keySet()) {
            sb.append(header + ":" + headers.getRequestHeader(header) + "\n");
        }        
        
        System.out.println(sb.toString());
                
        return Response.status(200).entity(valorCodificado).build();
    
    } catch (Exception e) {
        // TODO: handle exception
        return Response.status(500).entity("ERROR").build();
    }
}

和pom依赖：

<dependency>
    <groupId>org.jboss.resteasy</groupId>
    <artifactId>resteasy-multipart-provider</artifactId>
    <version>4.5.8.Final</version>
    <scope>provided</scope>
</dependency>

Answer 1

所以在 multipart 中，每个 body 部分都是自己独立的实体，有自己独立的 content-type。如果客户端请求中的每个部分都没有设置content-type，则默认为text/plain。在 RESTEasy 实现的情况下，它是 text/plain; charset=ISO-8859-1.

InputPart.DEFAULT_CONTENT_TYPE_PROPERTY
If no content-type header is sent in a multipart message part "text/plain; charset=ISO-8859-1" is assumed.

很多客户无法为每个部分设置content-type header。所以你应该做的是为他们设置 content-type header 。对于这一部分，您希望它是 application/json; chartset=utf-8。如何设置 header 是通过获取 InputPart from the MultiPartFormDataInput。不使用 getFormDataPart() 方法，而是使用 getFormDataMap() 方法来获取 Map<String, List<InputPart>> return 类型。从那里获取 InputPart 并调用 InputPart#setMediaTye()，然后您可以获得具有 InputPart#getBody() 变体之一的数据。类似（未测试）：

Map<String, List<InputPart>> inputParts = multipart.getFormDataMap();
List<InputPart> dataParts = inputParts.get("data");
if (dataParts != null && !dataParts.isEmpty()) {
    InputPart dataPart = dataParts.get(0);
    dataPart.setMediaType(MediaType.APPLICATION_JSON + "; chartset=utf-8");
    String dataPartJson = dataPart.getBody(String.class, null);
    // of if you make a POJO the data will get deserialized by Jackson
    DataPojo dataPartPogo = dataPart.getBody(DataPojo.class, null);
}

Java JSON 字符串编码Multipart问题

Java JSON String problem encoding Multipart

java

json

jax-rs

multipartform-data