HTTP/1.1 200 OK
content-length: 0
connection: close
date: Thu, 05 Dec 2019 01:58:03 GMT
etag: "358e8c8b1bfa35ee3bd44cb3d2cc416b"
server: tencent-cos
x-cos-hash-crc64ecma: 15060521397700495958
x-cos-request-id: NWRlODY0MmJfMjBiNDU4NjRfNjkyZl80ZjZi****

HTTP/1.1 200 OK
content-type: application/xml
transfer-encoding: chunked
connection: close
date: Thu, 05 Dec 2019 02:01:17 GMT
server: tencent-cos
x-cos-hash-crc64ecma: 15060521397700495958
x-cos-request-id: NWRlODY0ZWRfMjNiMjU4NjRfOGQ4Ml81MDEw****

[Object Content]

# -*- coding=utf-8
from qcloud_cos import CosConfig
from qcloud_cos import CosS3Client
from qcloud_cos import CosServiceError
from qcloud_cos import CosClientError
import sys
import logging
import hashlib
import crcmod

logging.basicConfig(level=logging.INFO, stream=sys.stdout)

# Configure user attributes, including SecretId, SecretKey, and region
# APPID has been removed from the configuration. Please specify it using the `Bucket` parameter in the format of `BucketName-APPID`.
secret_id = COS_SECRETID           # Replace with your own SecretId
secret_key = COS_SECRETKEY         # Replace with your own SecretKey
region = 'ap-beijing'      # Replace with your own region (which is Beijing in this sample)
token = None               # If a temporary key is used, the token needs to be specified. This is optional and is left empty by default.
config = CosConfig(Region=region, SecretId=secret_id, SecretKey=secret_key, Token=token)  # Get the configured object
client = CosS3Client(config)

OBJECT_PART_SIZE = 1024 * 1024      # Size of each simulated part
OBJECT_TOTAL_SIZE = OBJECT_PART_SIZE * 1 + 123      # Total size of the object
object_body = '1' * OBJECT_TOTAL_SIZE       # Object content

#Calculate the checksum of the entire object.
c64 = crcmod.mkCrcFun(0x142F0E1EBA9EA3693, initCrc=0, xorOut=0xffffffffffffffff, rev=True)
local_crc64 =str(c64(object_body))

# Initialize the multipart upload
response = client.create_multipart_upload(
    Bucket='examplebucket-1250000000',  #Replace with your own bucket name and APPID
    Key='exampleobject',              # Replace with the key value of your uploaded object
    StorageClass='STANDARD',            # Storage class of the object
)
#Get the UploadId of the multipart upload
upload_id = response['UploadId']

#Upload an object in parts where the size of each part is OBJECT_PART_SIZE except the last part which may be smaller
part_list = list()
position = 0 
left_size = OBJECT_TOTAL_SIZE
part_number = 0 
while left_size > 0:
    part_number += 1
    if left_size >= OBJECT_PART_SIZE:
        body = object_body[position:position+OBJECT_PART_SIZE]
    else:
        body = object_body[position:]
    position += OBJECT_PART_SIZE
    left_size -= OBJECT_PART_SIZE
    local_part_crc_64 = c64(body)#Calculate CRC64 locally

    response = client.upload_part(
        Bucket='examplebucket-1250000000',
        Key='exampleobject',
        Body=body,
        PartNumber=part_number,
        UploadId=upload_id,
    )   
    part_crc_64 = response['x-cos-hash-crc64ecma']# CRC64 returned by the server
    if local_part_crc64 != part_crc_64:# Data Check
        print 'crc64 check FAIL'
        exit(-1)
    etag = response['ETag']
    part_list.append({'ETag' : etag, 'PartNumber' : part_number})

#Complete the multipart upload
response = client.complete_multipart_upload(
    Bucket='examplebucket-1250000000',  #Replace with your own bucket name and APPID
    Key=‘exampleobject’,             #Key value of the object
    UploadId=upload_id,
    MultipartUpload={       #Require one-to-one correspondence between ETag and PartNumber for each part
        'Part' : part_list    
    },
)
crc64ecma = response['x-cos-hash-crc64ecma']
if crc64ecma != local_crc64:# Data Check
    print 'check crc64 Failed'
    exit(-1)

String calculateCrc64(File localFile) throws IOException {
    CRC64 crc64 = new CRC64();

    try (FileInputStream stream = new FileInputStream(localFile)) {
        byte[] b = new byte[1024 * 1024];
        while (true) {
            final int read = stream.read(b);
            if (read <= 0) {
                break;
            }
            crc64.update(b, read);
        }
    }

    return Long.toUnsignedString(crc64.getValue());
}

// For more information about how to create COSClient, see [Getting Started](https://www.tencentcloud.com/document/product/436/10199).
ObjectMetadata cosMeta = COSClient().getObjectMetadata(bucketName, cosFilePath); 
String cosCrc64 = cosMeta.getCrc64Ecma();
String localCrc64 = calculateCrc64(localFile);

if (cosCrc64.equals(localCrc64)) {
    System.out.println("ok");
} else {
    System.out.println("fail");
}