Object Storage Service:進捗バー

使用上の注意

• このトピックでは、中国 (杭州) リージョンのパブリックエンドポイントを使用します。 OSSと同じリージョンにある他のAlibaba CloudサービスからOSSにアクセスする場合は、内部エンドポイントを使用します。 OSSリージョンとエンドポイントの詳細については、「リージョン、エンドポイント、オープンポート」をご参照ください。

• このトピックでは、アクセス資格情報は環境変数から取得します。 アクセス資格情報の設定方法の詳細については、「アクセス資格情報の設定」をご参照ください。

• このトピックでは、OSSエンドポイントを使用してOSSClientインスタンスを作成します。 カスタムドメイン名またはSecurity Token Service (STS) を使用してOSSClientインスタンスを作成する場合は、「OSSClientインスタンスの作成」をご参照ください。

サンプルコード

次のコードでは、ossClient.putObjectメソッドを使用してオブジェクトをアップロードするときに進行状況バーを使用する方法の例を示します。

import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import com.aliyun.oss.event.ProgressEvent;
import com.aliyun.oss.event.ProgressEventType;
import com.aliyun.oss.event.ProgressListener;
import com.aliyun.oss.model.PutObjectRequest;
import java.io.File;

// Use the ProgressListener method to use the progress bar.
public class PutObjectProgressListenerDemo implements ProgressListener {
    private long bytesWritten = 0;
    private long totalBytes = -1;
    private boolean succeed = false;

    public static void main(String[] args) throws Exception {
        // In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint. 
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket. Example: examplebucket. 
        String bucketName = "examplebucket";
        // Specify the full path of the object. Do not include the bucket name in the full path. Example: exampledir\exampleobject.txt. 
        String objectName = "exampledir/exampleobject.txt";
        // Specify the full path of the local file. Example: D:\\localpath\\examplefile.txt. 
        String pathName = "D:\\localpath\\examplefile.txt";
        // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
        String region = "cn-hangzhou";

        // Create an OSSClient instance. 
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {
            // Specify the parameters of the progress bar when you upload the object. In this example, PutObjectProgressListenerDemo specifies the name of the class that you want to call. Replace it with an actual class name. 
            ossClient.putObject(new PutObjectRequest(bucketName,objectName, new File(pathName)).
                    <PutObjectRequest>withProgressListener(new PutObjectProgressListenerDemo()));
            // Specify the parameters of the progress bar when you download the object. In this example, GetObjectProgressListenerDemo specifies the name of the class that you want to call. Replace it with an actual class name. 
//            ossClient.getObject(new GetObjectRequest(bucketName,objectName).
//                    <GetObjectRequest>withProgressListener(new GetObjectProgressListenerDemo()));

        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }

    public boolean isSucceed() {
        return succeed;
    }

    // Rewrite the callback method to use the progress bar. The following sample code provides an example: 
    @Override
    public void progressChanged(ProgressEvent progressEvent) {
        long bytes = progressEvent.getBytes();
        ProgressEventType eventType = progressEvent.getEventType();
        switch (eventType) {
            case TRANSFER_STARTED_EVENT:
                System.out.println("Start to upload......");
                break;
            case REQUEST_CONTENT_LENGTH_EVENT:
                this.totalBytes = bytes;
                System.out.println(this.totalBytes + " bytes in total will be uploaded to OSS");
                break;
            case REQUEST_BYTE_TRANSFER_EVENT:
                this.bytesWritten += bytes;
                if (this.totalBytes != -1) {
                    int percent = (int)(this.bytesWritten * 100.0 / this.totalBytes);
                    System.out.println(bytes + " bytes have been written at this time, upload progress: " + percent + "%(" + this.bytesWritten + "/" + this.totalBytes + ")");
                } else {
                    System.out.println(bytes + " bytes have been written at this time, upload ratio: unknown" + "(" + this.bytesWritten + "/...)");
                }
                break;
            case TRANSFER_COMPLETED_EVENT:
                this.succeed = true;
                System.out.println("Succeed to upload, " + this.bytesWritten + " bytes have been transferred in total");
                break;
            case TRANSFER_FAILED_EVENT:
                System.out.println("Failed to upload, " + this.bytesWritten + " bytes have been transferred");
                break;
            default:
                break;
        }
    }
}

関連ドキュメント

オブジェクトアップロードのプログレスバーの完全なサンプルコードの詳細については、GitHubをご覧ください。