/**
* Rename a snapshot
*
* @param path The directory path where the snapshot was taken. Used for generating exception
* message.
* @param oldName Old name of the snapshot
* @param newName New name the snapshot will be renamed to
* @throws SnapshotException Throw SnapshotException when either the snapshot with the old name
* does not exist or a snapshot with the new name already exists
*/
public void renameSnapshot(String path, String oldName, String newName) throws SnapshotException {
if (newName.equals(oldName)) {
return;
}
final int indexOfOld = searchSnapshot(DFSUtil.string2Bytes(oldName));
if (indexOfOld < 0) {
throw new SnapshotException(
"The snapshot " + oldName + " does not exist for directory " + path);
} else {
final byte[] newNameBytes = DFSUtil.string2Bytes(newName);
int indexOfNew = searchSnapshot(newNameBytes);
if (indexOfNew > 0) {
throw new SnapshotException(
"The snapshot " + newName + " already exists for directory " + path);
}
// remove the one with old name from snapshotsByNames
Snapshot snapshot = snapshotsByNames.remove(indexOfOld);
final INodeDirectory ssRoot = snapshot.getRoot();
ssRoot.setLocalName(newNameBytes);
indexOfNew = -indexOfNew - 1;
if (indexOfNew <= indexOfOld) {
snapshotsByNames.add(indexOfNew, snapshot);
} else { // indexOfNew > indexOfOld
snapshotsByNames.add(indexOfNew - 1, snapshot);
}
}
}
