Performing a Partial Download

If you have any questions during development, post them on the Issues page of GitHub. For details about parameters and usage of each API, see the .

When only partial data of an object is required, you can download data falling within a specific range. If the specified range is from 0 to 1,000, data from byte 0 to byte 1,000, 1,001 bytes in total, are returned. If the specified range is invalid, data of the whole object will be returned. Sample code is as follows:

// Hard-coded or plaintext AK/SK are risky. For security purposes, encrypt your AK/SK and store them in the configuration file or environment variables. In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, configure environment variables ACCESS_KEY_ID and SECRET_ACCESS_KEY_ID.
// Obtain an AK/SK pair on the management console. For details, see https://support.huaweicloud.com/eu/usermanual-ca/ca_01_0003.html.
String ak = System.getenv("ACCESS_KEY_ID");
String sk = System.getenv("SECRET_ACCESS_KEY_ID");
String endPoint = "https://your-endpoint";

// Create an ObsClient instance.
final ObsClient obsClient = new ObsClient(ak, sk, endPoint);

GetObjectRequest request = new GetObjectRequest("bucketname", "objectname");
// Set the start position and end position for downloading.
request.setRangeStart(0l);
request.setRangeEnd(1000l);
ObsObject obsObject = obsClient.getObject(request);

// Obtain data.
byte[] buf = new byte[1024];
InputStream in = obsObject.getObjectContent();
for (int n = 0; n != -1; ) {
    n = in.read(buf, 0, buf.length);
}

in.close();

• If the specified range is invalid (because the start or end position is set to a negative integer or the range is larger than the object length), data of the whole object will be returned.
• Due to HTTP coding restrictions, non-ASCII characters cannot be sent. The SDK uses a URL to decode the information in the response header. For example, if content-disposition in your metadata is set to attachment; filename="%E4%B8%AD%E6%96%87.txt", the result obtained by the SDK is attachment; filename="Chinese characters.txt".
• If you do not need the SDK to decode for you, call GetObjectRequest.setIsEncodeHeaders(false) to disable auto decoding.
• You can also call obsObject.getMetadata().getOriginalHeaders() to obtain information about all original response headers.