/**
* Return an array containing hostnames, offset and size of portions of the given file. For a
* nonexistent file or regions, null will be returned.
*
* <p>This call is most helpful with DFS, where it returns hostnames of machines that contain the
* given file.
*
* <p>The FileSystem will simply return an elt containing 'localhost'.
*/
@Override
public BlockLocation[] getFileBlockLocations(FileStatus file, long start, long len)
throws IOException {
// Check if requested file in Swift is more than 5Gb. In this case
// each block has its own location -which may be determinable
// from the Swift client API, depending on the remote server
final FileStatus[] listOfFileBlocks = store.listSubPaths(file.getPath());
List<URI> locations = new ArrayList<URI>();
if (listOfFileBlocks.length > 1) {
for (FileStatus fileStatus : listOfFileBlocks) {
if (SwiftObjectPath.fromPath(uri, fileStatus.getPath())
.equals(SwiftObjectPath.fromPath(uri, file.getPath()))) {
continue;
}
if (fileStatus.getPath() != null) {
locations.addAll(store.getObjectLocation(fileStatus.getPath()));
}
}
} else {
locations = store.getObjectLocation(file.getPath());
}
final String[] names = new String[locations.size()];
final String[] hosts = new String[locations.size()];
int i = 0;
for (URI location : locations) {
hosts[i] = location.getHost();
names[i] = location.getAuthority();
i++;
}
return new BlockLocation[] {new BlockLocation(names, hosts, 0, file.getLen())};
}
