Initialization

Updated at：2025-11-03

Quick Start

Initialize a BosClient using STS authentication.

A BosClient is the interface to the BOS service. All BOS operations in the BOS Android SDK are executed through the BosClient.

Example code:

                Java
                
                BosClientConfiguration config = new BosClientConfiguration(); ////Initialize a BosClient with STS authentication
 config.setCredentials(new DefaultBceSessionCredentials(<AccessKeyID>, <SecretAccessKey>, <Token>); //Temporary AK/SK and Token returned by STS
 config.setEndpoint(<EndPoint>); //Pass in the domain name of the region where the bucket is located
BosClient client = new BosClient(config);

Create a bucket.

A bucket is a namespace in BOS that serves as a container for data and can hold multiple data entities (objects). You must create a bucket before uploading data.

Example code:
Java
```
1BosClient client = new BosClient(config);    //Create a BOSClient instance
2 client.createBucket(<BucketName>);     //Create a bucket and specify the bucket name
```

Upload an object.

An object is the basic data unit in BOS. You can think of an object as a file. For simple object uploads, BOS provides four methods: file upload, data stream upload, binary string upload, and string upload.

Example code:

                Java
                
            

                // Get specified file
 File file = new File(<FilePath>);     //Specify the file path
 // Upload object as a file
PutObjectResponse putObjectFromFileResponse = client.putObject(<BucketName>, <ObjectKey>, file);
 // Obtain data stream
InputStream inputStream = new FileInputStream(<FilePath>);
 // Upload an object in the form of a data stream
PutObjectResponse putObjectResponseFromInputStream = client.putObject(<BucketName>, <ObjectKey>, inputStream);
 // Upload object as binary string
PutObjectResponse putObjectResponseFromByte = client.putObject(<BucketName>, <ObjectKey>, <byte>);
 // Upload object in string form
PutObjectResponse putObjectResponseFromString = client.putObject(<BucketName>, <ObjectKey>, <string>);
 // Print ETag
System.out.println(putObjectFromFileResponse.getETag());
            

View the list of objects within a bucket.

Once you've finished uploading a series of files, use the following code to list all objects within the bucket.

Example code:

                Java
                
            

                // Obtain all object information under the specified bucket
ListObjectsResponse listing = client.listObjects(<BucketName>);
 // Traverse all objects
for (BosObjectSummary objectSummary : listing.getContents()) {
  System.out.println("ObjectKey: " + objectSummary.getKey());
  }
            

Get the specified object.

Refer to the code below to fetch one or multiple objects.

Example code:

                Java
                
            

                //Obtain the object, with returned result BosObject object
BosObject object = client.getObject(<BucketName>, <ObjectKey>);
 // Retrieve ObjectMeta
ObjectMetadata meta = object.getObjectMetadata();
 //Obtain the object's input stream
InputStream objectContent = object.getObjectContent();
 // Process object
...
 // Close stream
objectContent.close();
            

Complete example

                Java
                
            

                import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import android.os.Bundle;
import com.baidubce.BceClientException;
import com.baidubce.BceServiceException;
import com.baidubce.auth.DefaultBceCredentials;
import com.baidubce.development.AppSettings;
import com.baidubce.development.BaseActivity;
import com.baidubce.development.R;
import com.baidubce.services.bos.BosClient;
import com.baidubce.services.bos.BosClientConfiguration;
import com.baidubce.services.bos.model.BosObject;
import com.baidubce.services.bos.model.BosObjectSummary;
import com.baidubce.services.bos.model.CreateBucketResponse;
import com.baidubce.services.bos.model.ListObjectsResponse;
import com.baidubce.services.bos.model.ObjectMetadata;
import com.baidubce.services.bos.model.PutObjectResponse;
import com.baidubce.util.BLog;
public class ExampleActivity extends BaseActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 //Enable BOS SDK runtime logs
        BLog.enableLog();
        
 BosClientConfiguration config = new BosClientConfiguration(); ////Initialize a BosClient with STS authentication
 config.setCredentials(new DefaultBceSessionCredentials(<AccessKeyID>, <SecretAccessKey>, <Token>); //Temporary AK/SK and Token returned by STS
 config.setEndpoint(<EndPoint>);   //the region where the bucket is located
        final BosClient client = new BosClient(config);
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
 //Create Bucket
 CreateBucketResponse response = client.createBucket(<BucketName>);   //Create a bucket and specify the bucket name
                    System.out.println(response.getLocation());
                    System.out.println(response.getName());
 //Upload Object
 File file = new File(<Path>);//Directory of the uploaded file
                    PutObjectResponse putObjectFromFileResponse = client.putObject(<BucketName>, <ObjectKey>, file);
                    System.out.println(putObjectFromFileResponse.getETag());
 // View Object
                    ListObjectsResponse list = client.listObjects(<BucketName>);
                    for (BosObjectSummary objectSummary : list.getContents()) {
                        System.out.println("ObjectKey: " + objectSummary.getKey());
                    }
 // Get Object
                    BosObject object = client.getObject(<BucketName>, <ObjectKey>);
 // Retrieve ObjectMeta
                    ObjectMetadata meta = object.getObjectMetadata();
 //Obtain the object's input stream
                    InputStream objectContent = object.getObjectContent();
 // Process object
 FileOutputStream fos=new FileOutputStream(<Path>);//Directory/filename of the downloaded file
                    byte[] buffer=new byte[2048];
                    int count=0;
                    while ((count=objectContent.read(buffer))>=0) {
                        fos.write(buffer,0,count);
                    }
 // Close stream
                    objectContent.close();
                    fos.close();
                    System.out.println(meta.getETag());
                    System.out.println(meta.getContentLength());
                }catch (BceServiceException e) {
                    System.out.println("Error ErrorCode: " + e.getErrorCode());
                    System.out.println("Error RequestId: " + e.getRequestId());
                    System.out.println("Error StatusCode: " + e.getStatusCode());
                    System.out.println("Error Message: " + e.getMessage());
                    System.out.println("Error ErrorType: " + e.getErrorType());
                } catch (BceClientException e) {
                    System.out.println("Error Message: " + e.getMessage());
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }).start();
    }
}
            

Create a new BosClient with STS authentication

BosClient acts as the client for BOS services, offering developers numerous methods to interact with BOS. Before using the SDK to send requests to BOS, ensure you initialize a BosClient instance and configure the required settings.

Note: Android SDK is primarily used for mobile development scenarios. Mobile an untrusted environment, and there is a high risk of directly saving AccessKeyId and SecretAccessKey in the terminal for signing requests. Therefore, it is recommended to use the STS authentication mode. For detailed introduction to STS, please refer to [Temporary Authorization Access](BOS/API Reference/Access control.md#Temporary authorized access).

When using the STS method, you need to first create a BOSClient with STS to execute when calling the API. Currently, BOS STS only supports API calls in the following methods:

DeleteObject
PutObject
ListParts
GetObject
DoesBucketExist
CompleteMultipartUpload
AbortMultipartUpload
InitiateMultipartUpload
UploadPart

Example code: Users may refer to the following code to create a BosClient with STS authentication:

                Java
                
                BosClientConfiguration config = new BosClientConfiguration(); ////Initialize a BosClient with STS authentication
 config.setCredentials(new DefaultBceSessionCredentials(<AccessKeyID>, <SecretAccessKey>, <Token>); //Temporary AK/SK and Token returned by STS
 config.setEndpoint(<EndPoint>); //Pass in the domain name of the region where the bucket is located. EndPoint refers to the domain name address of the BOS service in various regions, e.g., Beijing's domain name is bj.bcebos.com
  BosClient client = new BosClient(config);

Plain Text

1  > **Note:**`EndPoint`parameter must use region-specific domains. Baidu AI Cloud currently supports multiple regions. Please refer to[Region Selection Guide](Reference/Region Selection Instructions/Region.md).
2  >
3  > Currently, the supported regions include "North China-Beijing," "South China-Guangzhou" and "East China-Suzhou." Beijing region: `http://bj.bcebos.com`, Guangzhou region: `http://gz.bcebos.com`, Suzhou region: `http://su.bcebos.com`.

Configure HTTPS access to BOS

BOS supports HTTPS transport protocol. You can use HTTPS to access the BOS service in the BOS Android SDK in the following two ways:

Specify HTTPS in the endpoint:

Plain Text

1```java
2String endpoint = "https://bj.bcebos.com";
3String ak = "ak";
4String sk = "sk";
5BosClientConfiguration config = new BosClientConfigration();
6config.setEndpoint(endpoint);  
7config.setCredentials(new DefaultBceCredentials(ak, sk));
8BosClient client = new BosClient(config);
9```

Configure HTTPS by calling setProtocol:

Plain Text

1```java
2String endpoint = "bj.bcebos.com"; // endpoint without protocol
3String ak = "ak";
4String sk = "sk";
5BosClientConfiguration config = new BosClientConfigration();
6config.setEndpoint(endpoint);  
7config.setCredentials(new DefaultBceCredentials(ak, sk));
8 config.setProtocol(Protocol.HTTPS); // Defaults to HTTP if unspecified
9BosClient client = new BosClient(config);
10```
11    > **Note**: If the endpoint already includes a protocol, the one in endpoint takes effect, and the setProtocol() method will be ignored.
12
13```java
14String endpoint = "http://bj.bcebos.com";
15String ak = "ak";
16String sk = "sk";
17BosClientConfiguration config = new BosClientConfigration();
18config.setEndpoint(endpoint);
19config.setCredentials(new DefaultBceCredentials(ak, sk));
20 config.setProtocol(Protocol.HTTPS); // Invalid operation if specified in endpoint, applicable to HTTP cases
21BosClient client = new BosClient(config);
22```

Configure BosClient

To configure specific parameters for BosClient, pass a BosClientConfiguration object during its construction. BosClientConfiguration serves as the configuration class for BOS services, allowing you to set fundamental network parameters.

Set network parameters

Use BosClientConfiguration to define key network parameters.

Example code

Plain Text

1```java
2BosClientConfiguration config = new BosClientConfiguration();
3 // Set maximum number of HTTP connections to 10
4config.setMaxConnections(10);
5 // Set TCP connection timeout to 5,000 milliseconds
6config.setConnectionTimeout(5000);
7 // Set timeout for Socket data transmission to 2,000 milliseconds
8config.setSocketTimeout(2000);
9```

Parameter description

The following parameters can be configured via BosClientConfiguration:

Parameters	Description
UserAgent	User agent, refers to HTTP’s User-Agent header
Protocol	Connection protocol type, default value HTTP protocol
LocalAddress	Local address
ConnectionTimeoutInMillis	Timeout duration for establishing connections (unit: ms), with a default value of 30000
SocketTimeoutInMillis	Timeout duration for data transmission through the opened connections (unit: ms), with a default value of 30000
MaxConnections	Maximum allowable HTTP connections, with a default value of 5
RetryPolicy	Retry policy for connections
SocketBufferSizeInBytes	Buffer size for socket operations
StreamBufferSize	Stream file buffer size
Ipv4Priority	IPv4 preferred, default value false

Version Change Records

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