/**
* Factory method to create {@link StorageDir}
*
* <p>It will load meta data of existing committed blocks in the dirPath specified. Only files
* with directory depth 1 under dirPath and whose file name can be parsed into {@code long} will
* be considered as existing committed blocks, these files will be preserved, others files or
* directories will be deleted.
*
* @param tier the {@link StorageTier} this dir belongs to
* @param dirIndex the index of this dir in its tier
* @param capacityBytes the initial capacity of this dir, can not be modified later
* @param dirPath filesystem path of this dir for actual storage
* @return the new created StorageDir
* @throws IOException when meta data of existing committed blocks can not be loaded
*/
public static StorageDir newStorageDir(
StorageTier tier, int dirIndex, long capacityBytes, String dirPath) throws IOException {
StorageDir dir = new StorageDir(tier, dirIndex, capacityBytes, dirPath);
dir.initializeMeta();
return dir;
}
