java @MultipartForm 如何获取原始文件名？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/26333298/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
@MultipartForm How to get the original file name?
提问by Krishna Chaitanya
I am using jboss's rest-easy multipart provider for importing a file. I read here http://docs.jboss.org/resteasy/docs/1.0.0.GA/userguide/html/Content_Marshalling_Providers.html#multipartform_annotationregarding @MultipartForm because I can exactly map it with my POJO.
我正在使用 jboss 的 rest-easy 多部分提供程序来导入文件。我在这里阅读了关于@MultipartForm 的http://docs.jboss.org/resteasy/docs/1.0.0.GA/userguide/html/Content_Marshalling_Providers.html#multipartform_annotation，因为我可以将它与我的 POJO 准确映射。
Below is my POJO
下面是我的 POJO
public class SoftwarePackageForm {
@FormParam("softwarePackage")
private File file;
private String contentDisposition;
public File getFile() {
return file;
}
public void setFile(File file) {
this.file = file;
}
public String getContentDisposition() {
return contentDisposition;
}
public void setContentDisposition(String contentDisposition) {
this.contentDisposition = contentDisposition;
}
}
Then I got the file object and printed its absolute path and it returned a file name of type file. The extension and uploaded file name are lost. My client is trying to upload a archive file(zip,tar,z)
然后我得到了文件对象并打印了它的绝对路径，它返回了一个文件类型的文件名。扩展名和上传的文件名丢失。我的客户正在尝试上传存档文件（zip、tar、z）
I need this information at the server side so that I can apply the un-archive program properly.
我在服务器端需要此信息，以便我可以正确应用取消归档程序。
The original file name is sent to the server in content-disposition header.
原始文件名在 content-disposition 标头中发送到服务器。
How can I get this information? Or atleast how can I say jboss to save the file with the uploaded file name and extension? Is it configurable from my application?
我怎样才能得到这些信息？或者至少我怎么能说 jboss 用上传的文件名和扩展名保存文件？它可以从我的应用程序配置吗？
回答by ivan.sim
After looking around a bit for Resteasy examples including this one, it seems like there is no way to retrieve the original filename and extension information when using a POJO class with the @MultipartFormannotation.
环视了一下对RestEasy的例子包括在此之后一个，好像是没有办法使用与一个POJO类时恢复原始文件名和扩展信息@MultipartForm的注释。
The examples I have seen so far retrieve the filename from the Content-Dispositionheader from the "file" part of the submitted multiparts form data via HTTP POST, which essentially, looks something like:
到目前为止，我所看到的示例Content-Disposition通过 HTTP POST 从提交的多部分表单数据的“文件”部分的标头中检索文件名，本质上类似于：
Content-Disposition: form-data; name="file"; filename="your_file.zip"
Content-Type: application/zip
You will have to update your file upload REST service class to extract this header like this:
您必须更新您的文件上传 REST 服务类以提取此标头，如下所示：
@POST
@Path("/upload")
@Consumes("multipart/form-data")
public Response uploadFile(MultipartFormDataInput input) {
String fileName = "";
Map<String, List<InputPart>> formParts = input.getFormDataMap();
List<InputPart> inPart = formParts.get("file"); // "file" should match the name attribute of your HTML file input
for (InputPart inputPart : inPart) {
try {
// Retrieve headers, read the Content-Disposition header to obtain the original name of the file
MultivaluedMap<String, String> headers = inputPart.getHeaders();
String[] contentDispositionHeader = headers.getFirst("Content-Disposition").split(";");
for (String name : contentDispositionHeader) {
if ((name.trim().startsWith("filename"))) {
String[] tmp = name.split("=");
fileName = tmp[1].trim().replaceAll("\"","");
}
}
// Handle the body of that part with an InputStream
InputStream istream = inputPart.getBody(InputStream.class,null);
/* ..etc.. */
}
catch (IOException e) {
e.printStackTrace();
}
}
String msgOutput = "Successfully uploaded file " + filename;
return Response.status(200).entity(msgOutput).build();
}
Hope this helps.
希望这可以帮助。
回答by lefloh
You could use @PartFilenamebut unfortunately this is currently only used for writing forms, not reading forms: RESTEASY-1069.
您可以使用@PartFilename但不幸的是，这目前仅用于编写表单，而不是读取表单：RESTEASY-1069。
Till this issue is fixed you could use MultipartFormDataInputas parameter for your resource method.
在修复此问题之前，您可以将其MultipartFormDataInput用作资源方法的参数。
回答by Αλ?κο?
It seems that Isim is right, but there is a workaround.
似乎 Isim 是对的，但有一个解决方法。
Create a hidden field in your form and update its value with the selected file's name. When the form is submitted, the filename will be submitted as a @FormParam.
在表单中创建一个隐藏字段并使用所选文件的名称更新其值。提交表单时，文件名将作为@FormParam 提交。
Here is some code you could need (jquery required).
这是您可能需要的一些代码（需要 jquery）。
<input id="the-file" type="file" name="file">
<input id="the-filename" type="hidden" name="filename">
<script>
$('#the-file').on('change', function(e) {
var filename = $(this).val();
var lastIndex = filename.lastIndexOf('\');
if (lastIndex < 0) {
lastIndex = filename.lastIndexOf('/');
}
if (lastIndex >= 0) {
filename = filename.substring(lastIndex + 1);
}
$('#the-filename').val(filename);
});
</script>
