Object Storage Service：Java進度條

注意事項

• 本文以華東1（杭州）外網Endpoint為例。如果您希望通過與OSS同地區的其他阿里雲產品訪問OSS，請使用內網Endpoint。關於OSS支援的Region與Endpoint的對應關係，請參見訪問網域名稱和資料中心。

• 本文以從環境變數讀取存取憑證為例。如何配置訪問憑證，請參見Java配置訪問憑證。

• 本文以OSS網域名稱建立OSSClient為例。如果您希望通過自訂網域名、STS等方式建立OSSClient，請參見建立OSSClient。

範例程式碼

以下代碼用於示範通過ossClient.putObject上傳檔案時使用進度條的方法：

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;

// 使用進度條，需要實現ProgressListener方法
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 {
        // Endpoint以華東1（杭州）為例，其它Region請按實際情況填寫。
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // 從環境變數中擷取訪問憑證。運行本程式碼範例之前，請確保已設定環境變數OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // 填寫Bucket名稱，例如examplebucket。
        String bucketName = "examplebucket";
        // 填寫Object完整路徑，完整路徑中不能包含Bucket名稱。例如exampledir/exampleobject.txt。
        String objectName = "exampledir/exampleobject.txt";
        // 填寫本地檔案的完整路徑，例如D:\\localpath\\examplefile.txt。
        String pathName = "D:\\localpath\\examplefile.txt";

        // 建立OSSClient執行個體。
        OSS ossClient = new OSSClientBuilder().build(endpoint, credentialsProvider);

        try {
            // 上傳檔案的同時指定進度條參數。此處PutObjectProgressListenerDemo為調用類的類名，請在實際使用時替換為相應的類名。
            ossClient.putObject(new PutObjectRequest(bucketName,objectName, new File(pathName)).
                    <PutObjectRequest>withProgressListener(new PutObjectProgressListenerDemo()));
            // 下載檔案的同時指定進度條參數。此處GetObjectProgressListenerDemo為調用類的類名，請在實際使用時替換為相應的類名。
//            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;
    }

    // 使用進度條需要您重寫回調方法，以下僅為參考樣本。
    @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;
        }
    }
}

相關文檔

關於上傳檔案時進度條使用方法的完整範例程式碼，請參見GitHub。