public void upgrade()
{
outputHandler.output("Upgrading " + sstable);
AbstractCompactionIterable ci = new CompactionIterable(compactionType, strategy.getScanners(this.toUpgrade), controller);
CloseableIterator<AbstractCompactedRow> iter = ci.iterator();
Collection<SSTableReader> sstables = new ArrayList<SSTableReader>();
Collection<SSTableWriter> writers = new ArrayList<SSTableWriter>();
try