Java 多部分文件到文件 InputStream
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Multipart File to File InputStream
提问by
How can I convert a MultipartFileto FileInputStreamin memory?
我怎么能转换MultipartFile到FileInputStream内存中？
I have tried to below , but i am facing the error as
我已经尝试在下面，但我面临的错误是
org.springframework.web.multipart.commons.CommonsMultipartFile cannot be cast to java.io.File
org.springframework.web.multipart.commons.CommonsMultipartFile 不能转换为 java.io.File
My Code is
我的代码是
FileInputStream fis = new FileInputStream((File)file);
where file is a multipart file
其中 file 是一个多部分文件
回答by Amey Jadiye
Take look at MultipartFile
In that you can go with :
你可以使用：
void transferTo(File dest)
This method transfer the received file to the given destination file.
此方法将接收到的文件传输到给定的目标文件。
回答by PyThon
You can't create an instance of FileInputStream unless your file is not on file system.
除非您的文件不在文件系统上，否则您无法创建 FileInputStream 的实例。
You have to either first save the multipart file in temporary location on server using
您必须首先使用以下方法将多部分文件保存在服务器上的临时位置
file.transferTo(tempFile);
InputStream stream = new FileInputStream(tempFile);
But multipart file can also be read simply via basic streams methods such as
但是也可以通过基本的流方法简单地读取多部分文件，例如
InputStream inputStream = new BufferedInputStream(file.getInputStream());
回答by Akshay
For a multipart file eg:
对于多部分文件，例如：
FileMultipartData part = new FileMultipartData();
InputStream inputStream = part.getFileMultipart().get(0).getByteStream();
This worked for me in my code. Please try it
这在我的代码中对我有用。请尝试一下
回答by P.Saranya
Try using:
尝试使用：
MultipartFile uploadedFile = ((MultipartHttpServletRequest)request).getFile('file_name')
InputStream inputStream = new ByteArrayInputStream(uploadedFile?.getBytes())
回答by Gaurav Kumar
To convert Multipart file to Input Stream
将多部分文件转换为输入流
MultipartFile file;
InputStream inputStream = new InputStream(file.getInputStream());
This worked for me.
这对我有用。
