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 will decode the information in response headers using URL decoding rules.
- 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.