Java Convert FilePart to byte[] in Springboot using Webflux

Question

I want to get the byte content of the File. Here is my controller:

@PostMapping("/files")
@ResponseStatus(HttpStatus.OK)
public List<UserFilesResponse> uploadFile(@RequestPart("file") FilePart file) {

// I want to get the bytes[] content of my file. How can I do it please ??
}

Answer 1

As M. Deinum mentioned, you should use content

I would also recommend https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/core/io/buffer/DataBufferUtils.html#join-org.reactivestreams.Publisher-

DataBufferUtils.join(filePart.content())
    .map(dataBuffer -> dataBuffer.asByteBuffer().array())

Answer 2

Convert filepart to Byte Array

private byte[] convertFilePartToByteArray(FilePart file) throws IOException {
        File convFile = new File(file.filename());
        file.transferTo(convFile);
        return Files.readAllBytes(convFile.toPath());
    }

Answer 3

@ResponseStatus(HttpStatus.OK)
public List<UserFilesResponse> uploadFile(@RequestPart("file") MultipartFile file) {

byte[] fileBytes = file.getBytes();

//rest of code
}

I would suggest to use multipart file instead of just file part, this will enable you to call the getBytes() method and get the byte array.