如何使用RESTeasy从multipart / form-data请求获取text / xml为UTF-8？

Question

谢谢你的回答，但使用InputStream而不是使用getBody（...）也行不通。 下面的代码返回与原始帖子中的结果相同的结果。

final InputStream inStream = fileUploadInput.getFormDataPart(searchedInput, InputStream.class, null);
// get bytes
final byte[] inBytes = new byte[1024];
final ByteArrayOutputStream outBytes = new ByteArrayOutputStream(inBytes.length);
int length = 0;
while((length = inStream.read(inBytes)) >= 0) {
    outBytes.write(inBytes, 0, length);
}
final byte[] rawInput = outBytes.toByteArray();

// get Encoding
final String asciiInput = new String(rawInput, ASCII);
final String utf8 = new String(rawInput, UTF8);
final String isoLatin1 = new String(rawInput, ISO8859_1);       
log.info("ASCII: " + ascii);
log.info("UTF8: " + utf8);
log.info("ISOLATIN1: " + isoLatin1);
return utf8;

原始邮寄：

我想使用下面的HTML表单上传UTF-8编码的XML文件，并使用RESTEasy MultipartFormDataInput和下面显示的Java代码在服务器上读取它。 在服务器端，我似乎得到了ASCII编码文件的内容，与上传文件的实际编码（UTF-8）无关（以下面描述的方式访问它）。 所有不属于ASCII字符集的字符都被替换为? 。 如何从RESTeasy的'multipart / form-data'请求中将'text / xml'作为UTF-8？ （我知道可以编写一个PreProcessor - Interceptor并在那里获取原始字节，但我不能在我的应用程序中使用这种方法）。

上传表格：

<html>
<body>
    <h1>JAX-RS Upload Form</h1>

    <form action="http://.../upload" method="POST" enctype="multipart/form-data">

       <p>Select a file : <input type="file" name="upload"/></p>
       <input type="submit" value="Upload It" />

    </form>
</body>
</html>

资源类：

@Path("/upload")
@POST
@Consumes("multipart/form-data")
public Response createUploadTemplate(
        @Context HttpServletRequest req,
        MultipartFormDataInput formInput) {

    try {
        final String templateXml = getInput("upload", formInput);
        //...
    } catch (Exception e) {
        //...
    }
}

private static String getInput(final String searchedInput, final MultipartFormDataInput fileUploadInput) throws BadRequestException, IOException {

    try {
        final Map<String, List<InputPart>> inputToInputPart = fileUploadInput.getFormDataMap();

        if(inputToInputPart.containsKey(searchedInput)) {

            final StringBuilder builder = new StringBuilder();
            final List<InputPart> inputParts = inputToInputPart.get(searchedInput);

            for(InputPart inputPart : inputParts) {
                builder.append(inputPart.getBody(String.class,null));
            }

            return builder.toString();
        } else {
                throw new BadRequestException("The form send with the request does not contain an input element " + searchedInput + ".");
        }
    } catch(Exception e) {
        throw new BadRequestException("The file upload failed.", e);
    }
}

化MessageBodyReader：

@Provider
@Consumes ("text/xml")
public class XmlStringReader implements MessageBodyReader<String> {
    private static Logger log = LoggerFactory.getLogger(UploadedXmlStringReader.class);

    private static final String ASCII = "ASCII";
    private static final String ISO8859_1 = "ISO8859_1";
    private static final String UTF8 = "UTF8";

    @Override
    public boolean isReadable(final Class<?> type,
                                final Type genericType,
                                final Annotation[] annotations,
                                final MediaType mediaType) {

        boolean result = type.equals(String.class) && MediaType.TEXT_XML_TYPE.equals(mediaType);
        log.info(MessageFormat.format("{0} == String.class && MediaType.TEXT_XML_TYPE == {1}: {2}", type, mediaType, result));
        return result;
    }

    @Override
    public String readFrom(final Class<String> type,
                                        final Type genericType,
                                        final Annotation[] annotations,
                                        final MediaType mediaType,
                                        final MultivaluedMap<String, String> httpHeaders,
                                        final InputStream entityStream) throws IOException, WebApplicationException {

        final byte[] inBytes = new byte[1024];
        final ByteArrayOutputStream outBytes = new ByteArrayOutputStream(inBytes.length);
        int length = 0;

        while((length = entityStream.read(inBytes)) >= 0) {
            outBytes.write(inBytes, 0, length);
        }

        final byte[] rawInput = outBytes.toByteArray();
        final String ascii = new String(rawInput, ASCII);

        final String utf8 = new String(rawInput, UTF8);
        final String isoLatin1 = new String(rawInput, ISO8859_1);       

        log.info("ASCII: " + ascii);
        log.info("UTF8: " + utf8);
        log.info("ISOLATIN1: " + isoLatin1);

        return utf8;
    }
}

Answer 1

如果在HTTP请求的内容类型标头中未定义字符集，则resteasy会假定为“charset = US-ASCII”。 请参阅org.jboss.resteasy.plugins.providers.multipart.InputPart：

/**
    * If there is a content-type header without a charset parameter, charset=US-ASCII
    * is assumed.
    * <p>
    * This can be overwritten by setting a different String value in
    * {@link org.jboss.resteasy.spi.HttpRequest#setAttribute(String, Object)}
    * with this ("resteasy.provider.multipart.inputpart.defaultCharset")
    * String`enter code here` as key. It should be done in a
    * {@link org.jboss.resteasy.spi.interception.PreProcessInterceptor}.
    * </p>
     */

因此，作为一种解决方法，您可以执行以下操作：

 @Provider
@ServerInterceptor
public class CharsetPreProcessInterceptor implements PreProcessInterceptor {

    @Override
    public ServerResponse preProcess(HttpRequest request, ResourceMethod method) throws Failure, WebApplicationException {
        request.setAttribute(InputPart.DEFAULT_CHARSET_PROPERTY, "charset=UTF-8");
        return null;
    }

}

Answer 2

我一般不会依靠getBody的方法InputPart 。 您实际上可以将每个部分作为原始输入流并自己读取数据。 而不是依靠框架将内容转换为String。

如何使用RESTeasy从multipart / form-data请求获取text / xml为UTF-8？

问题描述

原始邮寄：

2 个解决方案

解决方案1
4 2013-04-26 11:04:16

解决方案2
0 2012-03-19 10:58:43

如何使用RESTeasy从multipart / form-data请求获取text / xml为UTF-8？

问题描述

原始邮寄：

2 个解决方案

解决方案1 4 2013-04-26 11:04:16

解决方案2 0 2012-03-19 10:58:43

解决方案1
4 2013-04-26 11:04:16

解决方案2
0 2012-03-19 10:58:43