try {
// Create an S3 client using the provided access key, secret key, and region
S3Client s3Client = getAWSS3Client(accessKey, secretKey, region);
// List objects in the bucket with the specified prefix
ListObjectsV2Response listObjectsV2Response = s3Client.listObjectsV2(b -> b.bucket(bucketName).prefix(sourceFileName));
List<S3Object> objects = listObjectsV2Response.contents();
Long size = objects.get(0).size();
log.info(“size of the file is {}”, size);
// Check if the file size is 0 and throw an exception if it is
if (size == 0) {
throw new FileNotFoundException(“File is empty”);
}
long partSize = 1024 * 1024 * 10; // Set the part size to 10 MB
long contentLength = size;
FileOutputStream fos = new FileOutputStream(destinationFileName);
// Download the file in parts
for (long start = 0; start < contentLength; start += partSize) {
long end = Math.min(start + partSize – 1, contentLength – 1);
GetObjectRequest rangeGetObjectRequest = GetObjectRequest.builder()
.bucket(bucketName)
.key(sourceFileName)
.range(“bytes=” + start + “-“ + end)
.build();
ResponseInputStream<GetObjectResponse> responseInputStream = s3Client.getObject(rangeGetObjectRequest);
byte[] buffer = new byte[1024 * 1024 * 10];
int bytesRead;
while ((bytesRead = responseInputStream.read(buffer)) != –1) {
fos.write(buffer, 0, bytesRead);
}
responseInputStream.close();
}
fos.close();
} catch (Exception e) {
log.error(“Exception Occurred while downloading files for key {} “, e.getMessage());
throw new RuntimeException(e);
}
}
