BlockCommand getInvalidateBlocks ( int maxblocks ) { Block [ ] deleteList = null ; synchronized ( invalidateBlocks ) { deleteList = invalidateBlocks . pollToArray ( new Block [ Math . min ( invalidateBlocks . size ( ) , maxblocks ) ] ) ; } return ( deleteList == null || deleteList . length == 0 ) ? null : new BlockCommand ( DatanodeProtocol . DNA_INVALIDATE , deleteList ) ; }
Remove the specified number of blocks to be invalidated