Processing large files.

[Dzmitry-yarik]

There is a StandardMultipartFile class in Spring.
It has a getBytes method that looks like this:

public byte[] getBytes() throws IOException {
return FileCopyUtils.copyToByteArray(this.part.getInputStream());
}

I have a question. Is this a good approach for large files if I need to get byte[], because transferTo() returns void?

I suggest doing the upload in parts. For example, like this:

public byte[] getBytes(int chunkSize) throws IOException {
    long size = this.part.getSize();
    try (InputStream in = this.part.getInputStream();
         ByteArrayOutputStream baos = new ByteArrayOutputStream((int) size)) {

        byte[] buffer = new byte[chunkSize];
        int bytesRead;
        while ((bytesRead = in.read(buffer)) != -1) {
            baos.write(buffer, 0, bytesRead);
        }
        return baos.toByteArray();
    }
}

This is not an ideal option, just as an idea.

[bclozel]

Duplicates spring-projects/spring-boot#46934 (comment)
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