Example usage for com.amazonaws.services.s3.model ListObjectsV2Result getCommonPrefixes

Introduction

In this page you can find the example usage for com.amazonaws.services.s3.model ListObjectsV2Result getCommonPrefixes.

Prototype

public List<String> getCommonPrefixes() 

Source Link

Document

Gets the common prefixes included in this object listing.

Usage

From source file:alluxio.underfs.s3a.S3AUnderFileSystem.java

License:Apache License

/**
 * Lists the files in the given path, the paths will be their logical names and not contain the
 * folder suffix. Note that, the list results are unsorted.
 *
 * @param path the key to list//from w  w  w. jav  a 2 s  .c o  m
 * @param recursive if true will list children directories as well
 * @return an array of the file and folder names in this directory
 * @throws IOException if an I/O error occurs
 */
private String[] listInternal(String path, boolean recursive) throws IOException {
    path = stripPrefixIfPresent(path);
    path = PathUtils.normalizePath(path, PATH_SEPARATOR);
    path = path.equals(PATH_SEPARATOR) ? "" : path;
    String delimiter = recursive ? "" : PATH_SEPARATOR;
    Set<String> children = new HashSet<>();
    try {
        ListObjectsV2Request request = new ListObjectsV2Request().withBucketName(mBucketName).withPrefix(path)
                .withDelimiter(delimiter).withMaxKeys(LISTING_LENGTH);
        ListObjectsV2Result result = null;
        while (result == null || result.isTruncated()) {
            // Query S3 for the next batch of objects
            result = mClient.listObjectsV2(request);
            // Advance the request continuation token to the next set of objects
            request.setContinuationToken(result.getNextContinuationToken());

            // Directories in S3 UFS can be possibly encoded in two different ways:
            // (1) as file objects with FOLDER_SUFFIX for directories created through Alluxio or
            // (2) as "common prefixes" of other files objects for directories not created through
            // Alluxio
            //
            // Case (1) (and file objects) is accounted for by iterating over chunk.getObjects() while
            // case (2) is accounted for by iterating over chunk.getCommonPrefixes().
            //
            // An example, with prefix="ufs" and delimiter="/" and LISTING_LENGTH=5
            // - objects.key = ufs/, child =
            // - objects.key = ufs/dir1_$folder$, child = dir1
            // - objects.key = ufs/file, child = file
            // - commonPrefix = ufs/dir1/, child = dir1
            // - commonPrefix = ufs/dir2/, child = dir2

            // Handle case (1)
            for (S3ObjectSummary obj : result.getObjectSummaries()) {
                // Remove parent portion of the key
                String child = getChildName(obj.getKey(), path);
                // Prune the special folder suffix
                child = CommonUtils.stripSuffixIfPresent(child, FOLDER_SUFFIX);
                // Only add if the path is not empty (removes results equal to the path)
                if (!child.isEmpty()) {
                    children.add(child);
                }
            }
            // Handle case (2)
            for (String commonPrefix : result.getCommonPrefixes()) {
                // Remove parent portion of the key
                String child = getChildName(commonPrefix, path);
                // Remove any portion after the last path delimiter
                int childNameIndex = child.lastIndexOf(PATH_SEPARATOR);
                child = childNameIndex != -1 ? child.substring(0, childNameIndex) : child;
                if (!child.isEmpty() && !children.contains(child)) {
                    // This directory has not been created through Alluxio.
                    mkdirsInternal(commonPrefix);
                    children.add(child);
                }
            }
        }
        return children.toArray(new String[children.size()]);
    } catch (AmazonClientException e) {
        LOG.error("Failed to list path {}", path, e);
        return null;
    }
}

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From source file:org.exem.flamingo.web.filesystem.s3.S3BrowserController.java

License:Apache License

@RequestMapping(value = "listFolders", method = RequestMethod.GET)
@ResponseStatus(HttpStatus.OK)//from w ww  .  j av a 2s  .c  om
public Response listFolders(@RequestParam(required = false) String bucketName,
        @RequestParam(required = false) String prefix,
        @RequestParam(required = false) String continuationToken) {

    // Get bucket list
    if (StringUtils.isEmpty(bucketName)) {
        Response response = new Response();
        response.getList().addAll(getBucketList());
        response.setSuccess(true);
        return response;
    }

    // Get folder list
    ListObjectsV2Result result = s3BrowserService.listObjects(bucketName, prefix, continuationToken);

    List<S3ObjectInfo> list = new ArrayList<>();
    List<String> commonPrefixes = result.getCommonPrefixes();
    for (String key : commonPrefixes) {
        S3ObjectInfo object = new S3ObjectInfo();
        object.setKey(key);
        object.setName(getName(key));
        object.setBucketName(bucketName);
        object.setFolder(true);
        list.add(object);
    }

    Map<String, String> map = new HashMap<>();
    map.put(S3Constansts.CONTINUATIONTOKEN, result.getNextContinuationToken());
    map.put(S3Constansts.ISTRUNCATED, BooleanUtils.toStringTrueFalse(result.isTruncated()));

    Response response = new Response();
    response.getList().addAll(list);
    response.getMap().putAll(map);
    response.setSuccess(true);
    return response;
}

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From source file:org.exem.flamingo.web.filesystem.s3.S3BrowserController.java

License:Apache License

@RequestMapping(value = "listObjects", method = RequestMethod.GET)
@ResponseStatus(HttpStatus.OK)//from w ww.j  a  va2 s  .  c o m
public Response listObjects(@RequestParam(required = false) String bucketName,
        @RequestParam(required = false) String prefix,
        @RequestParam(required = false) String continuationToken) {
    // Get bucket list
    if (StringUtils.isEmpty(bucketName)) {
        Response response = new Response();
        response.getList().addAll(getBucketList());
        response.setSuccess(true);
        return response;
    }

    // Get folder & bucket list
    ListObjectsV2Result result = s3BrowserService.listObjects(bucketName, prefix, continuationToken);

    List<S3ObjectInfo> list = new ArrayList<>();
    List<String> commonPrefixes = result.getCommonPrefixes();
    for (String key : commonPrefixes) {
        S3ObjectInfo object = new S3ObjectInfo();
        object.setBucketName(bucketName);
        object.setKey(key);
        object.setName(getName(key));
        object.setFolder(true);
        list.add(object);
    }

    List<S3ObjectSummary> objectSummaries = result.getObjectSummaries();

    if (!StringUtils.endsWith(prefix, S3Constansts.DELIMITER)) {
        prefix = prefix + S3Constansts.DELIMITER;
    }
    for (S3ObjectSummary s3Object : objectSummaries) {
        String key = s3Object.getKey();
        if (prefix.equals(key)) {
            continue;
        }
        S3ObjectInfo object = new S3ObjectInfo();
        object.setBucketName(bucketName);
        object.setPrefix(prefix);
        object.setKey(key);
        object.setName(getName(key));
        object.setObject(true);
        object.setSize(s3Object.getSize());
        object.setLastModified(s3Object.getLastModified());
        object.setStorageClass(s3Object.getStorageClass());
        list.add(object);
    }

    Map<String, String> map = new HashMap<>();
    map.put(S3Constansts.CONTINUATIONTOKEN, result.getNextContinuationToken());
    map.put(S3Constansts.ISTRUNCATED, BooleanUtils.toStringTrueFalse(result.isTruncated()));

    Response response = new Response();
    response.getList().addAll(list);
    response.getMap().putAll(map);
    response.setSuccess(true);
    return response;
}

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