Overview

This document provides an overview of APIs and SDK code samples related to listing objects.

SDK API Reference

For the parameters and method descriptions of all the APIs in the SDK, please see SDK API Reference.

Querying an Object List

Feature description

This API is used to query some or all objects in a bucket.

Sample 1. Getting the first page of data

String bucketName = "examplebucket-1250000000"; // Format: BucketName-APPID
final GetBucketRequest getBucketRequest = new GetBucketRequest(bucketName);

// Prefix match, which is used to specify the address prefix of the returned objects
getBucketRequest.setPrefix("dir/");

// Maximum number of entries returned at a time. Default value: 1,000
getBucketRequest.setMaxKeys(100);

cosXmlService.getBucketAsync(getBucketRequest, new CosXmlResultListener() {
    @Override
    public void onSuccess(CosXmlRequest request, CosXmlResult result) {
        GetBucketResult getBucketResult = (GetBucketResult) result;
        if (getBucketResult.listBucket.isTruncated) {
            // The data is truncated, and the next page of data needs to be pulled
            prevPageResult = getBucketResult;
        }
    }

    @Override
    public void onFail(CosXmlRequest cosXmlRequest,
                       CosXmlClientException clientException,
                       CosXmlServiceException serviceException) {
        if (clientException != null) {
            clientException.printStackTrace();
        } else {
            serviceException.printStackTrace();
        }
    }
});

Note：

For more samples, please visit GitHub.

Sample 2. Requesting the next page of data

String bucketName = "examplebucket-1250000000"; // Format: BucketName-APPID


GetBucketRequest getBucketRequest = new GetBucketRequest(bucketName);

// Prefix match, which is used to specify the address prefix of the returned objects
getBucketRequest.setPrefix("dir/");

// `prevPageResult` is the result returned on the previous page, where `nextMarker` indicates the starting point of the next page
String nextMarker = prevPageResult.listBucket.nextMarker;
getBucketRequest.setMarker(nextMarker);

// Maximum number of entries returned at a time. Default value: 1,000
getBucketRequest.setMaxKeys(100);

cosXmlService.getBucketAsync(getBucketRequest, new CosXmlResultListener() {
    @Override
    public void onSuccess(CosXmlRequest request, CosXmlResult result) {
        GetBucketResult getBucketResult = (GetBucketResult) result;
        if (getBucketResult.listBucket.isTruncated) {
            // The data is truncated, and the next page of data needs to be pulled
        }
    }

    @Override
    public void onFail(CosXmlRequest cosXmlRequest,
                       CosXmlClientException clientException,
                       CosXmlServiceException serviceException) {
        if (clientException != null) {
            clientException.printStackTrace();
        } else {
            serviceException.printStackTrace();
        }
    }
});

Note：

For more samples, please visit GitHub.

Sample 3. Getting an object list and subdirectories

String bucketName = "examplebucket-1250000000"; // Format: BucketName-APPID
GetBucketRequest getBucketRequest = new GetBucketRequest(bucketName);

// Prefix match, which is used to specify the address prefix of the returned objects
getBucketRequest.setPrefix("dir/");

// Maximum number of entries returned at a time. Default value: 1,000
getBucketRequest.setMaxKeys(100);

// The delimiter is a symbol. If the prefix exists,
// identical paths between the prefix and delimiter will be grouped as together and defined as a common prefix,
// and then all common prefixes will be listed; otherwise, the listing will start from the beginning of the path
getBucketRequest.setDelimiter("/");

cosXmlService.getBucketAsync(getBucketRequest, new CosXmlResultListener() {
    @Override
    public void onSuccess(CosXmlRequest request, CosXmlResult result) {
        GetBucketResult getBucketResult = (GetBucketResult) result;
    }

    @Override
    public void onFail(CosXmlRequest cosXmlRequest,
                       CosXmlClientException clientException,
                       CosXmlServiceException serviceException) {
        if (clientException != null) {
            clientException.printStackTrace();
        } else {
            serviceException.printStackTrace();
        }
    }
});

Note：

For more samples, please visit GitHub.

Querying an Object Version List

Feature description

This API is used to query some or all objects in a versioning-enabled bucket.

Sample 1. Getting the object version list’s first page of data

String bucketName = "examplebucket-1250000000"; // Format: BucketName-APPID
final GetBucketObjectVersionsRequest getBucketRequest =
        new GetBucketObjectVersionsRequest(bucketName);

// Prefix match, which is used to specify the address prefix of the returned objects
getBucketRequest.setPrefix("dir/");

// Maximum number of entries returned at a time. Default value: 1,000
getBucketRequest.setMaxKeys(100);

cosXmlService.getBucketObjectVersionsAsync(getBucketRequest,
        new CosXmlResultListener() {
    @Override
    public void onSuccess(CosXmlRequest request, CosXmlResult result) {
        GetBucketObjectVersionsResult getBucketResult =
                (GetBucketObjectVersionsResult) result;
        if (getBucketResult.listVersionResult.isTruncated) {
            // The data is truncated, and the next page of data needs to be pulled
            prevPageResult = getBucketResult;
        }
    }

    @Override
    public void onFail(CosXmlRequest cosXmlRequest,
                       CosXmlClientException clientException,
                       CosXmlServiceException serviceException) {
        if (clientException != null) {
            clientException.printStackTrace();
        } else {
            serviceException.printStackTrace();
        }
    }
});

Note：

For more samples, please visit GitHub .

Sample 2. Getting the object version list’s next page of data

String bucketName = "examplebucket-1250000000"; // Format: BucketName-APPID
final GetBucketObjectVersionsRequest getBucketRequest =
        new GetBucketObjectVersionsRequest(bucketName);

// Prefix match, which is used to specify the address prefix of the returned objects
getBucketRequest.setPrefix("dir/");

// Maximum number of entries returned at a time. Default value: 1,000
getBucketRequest.setMaxKeys(100);

// `prevPageResult` is the result returned on the previous page, where `nextMarker` and `nextVersionIdMarker`
// indicate the starting point of the next page
getBucketRequest.setKeyMarker(prevPageResult.listVersionResult
        .nextKeyMarker);
getBucketRequest.setVersionIdMarker(prevPageResult.listVersionResult
        .nextVersionIdMarker);

cosXmlService.getBucketObjectVersionsAsync(getBucketRequest,
        new CosXmlResultListener() {
    @Override
    public void onSuccess(CosXmlRequest request, CosXmlResult result) {
        GetBucketObjectVersionsResult getBucketResult =
                (GetBucketObjectVersionsResult) result;
        if (getBucketResult.listVersionResult.isTruncated) {
            // The data is truncated, and the next page of data needs to be pulled
            prevPageResult = getBucketResult;
        }
    }

    @Override
    public void onFail(CosXmlRequest cosXmlRequest,
                       CosXmlClientException clientException,
                       CosXmlServiceException serviceException) {
        if (clientException != null) {
            clientException.printStackTrace();
        } else {
            serviceException.printStackTrace();
        }
    }
});

Note：

For more samples, please visit GitHub.