You can use a progress bar to indicate the progress of an object that is being uploaded or downloaded. This topic describes how to use a progress bar when you use the ossClient.getObject method to download an object.

Sample code

The following code provides an example on how to use a progress bar when you use the ossClient.getObject method to download an object.

Note The following methods support the progress bar feature: ossClient.putObject, ossClient.getObject, ossClient.uploadPart, ossClient.uploadFile, and ossClient.downloadFile. The procedure to apply progress bars to these methods is the same as that of the ossClient.putObject method.
import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
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.GetObjectRequest;

public class GetObjectProgressListener implements ProgressListener {
    private long bytesRead = 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 the actual endpoint. 
        String endpoint = "";
        // The AccessKey pair of an Alibaba Cloud account has permissions on all API operations. Using these credentials to perform operations in OSS is a high-risk operation. We recommend that you use a RAM user to call API operations or perform routine O&M. To create a RAM user, log on to the RAM console. 
        String accessKeyId = "yourAccessKeyId";
        String accessKeySecret = "yourAccessKeySecret";
        // Specify the name of the bucket. Example: examplebucket. 
        String bucketName = "examplebucket";
        // Specify the full path of the object. The full path of the object cannot contain the bucket name. Example: testfolder/exampleobject.txt. 
        String objectName = "testfolder/exampleobject.txt";
        String pathName = "D:\\localpath\\examplefile.txt";

        // Create an OSSClient instance. 
        OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);

        try {
            // Specify the parameter of the progress bar while downloading the object. 
            ossClient.getObject(new GetObjectRequest(bucketName, objectName).
                            <GetObjectRequest>withProgressListener(new GetObjectProgressListener()),
                    new File(pathName));
        } 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) {

    public void progressChanged(ProgressEvent progressEvent) {
        long bytes = progressEvent.getBytes();
        ProgressEventType eventType = progressEvent.getEventType();
        switch (eventType) {
            case TRANSFER_STARTED_EVENT:
                System.out.println("Start to download......");
                this.totalBytes = bytes;
                System.out.println(this.totalBytes + " bytes in total will be downloaded to a local file");
                this.bytesRead += bytes;
                if (this.totalBytes != -1) {
                    int percent = (int)(this.bytesRead * 100.0 / this.totalBytes);
                    System.out.println(bytes + " bytes have been read at this time, download progress: " +
                            percent + "%(" + this.bytesRead + "/" + this.totalBytes + ")");
                } else {
                    System.out.println(bytes + " bytes have been read at this time, download ratio: unknown" +
                            "(" + this.bytesRead + "/...)");
                this.succeed = true;
                System.out.println("Succeed to download, " + this.bytesRead + " bytes have been transferred in total");
            case TRANSFER_FAILED_EVENT:
                System.out.println("Failed to download, " + this.bytesRead + " bytes have been transferred");
    public boolean isSucceed() {
        return succeed;


For the complete sample code of progress bars in object download, visit GitHub.