code: @Override
  	protected void extendStoreFiles(int oldBlockCount, int newBlockCount) throws DataStoreException
      {
          try
          {
              // Update allocation table
              allocationTableRandomAccessFile.setLength(AT_HEADER_SIZE+(long)newBlockCount*AT_BLOCK_SIZE);
              for (int n = oldBlockCount ; n < newBlockCount ; n++)
                  writeAllocationBlock(n);
              allocationTableRandomAccessFile.seek(AT_HEADER_BLOCKCOUNT_OFFSET);
              allocationTableRandomAccessFile.writeInt(newBlockCount);
              
              // Update data file
              dataRandomAccessFile.setLength((long)blockSize*newBlockCount);
          }
          catch (IOException e)
          {
              throw new DataStoreException("Could not extends store to "+newBlockCount+" blocks : "+dataFile.getAbsolutePath(),e);
          }
      }
docs: /* (non-Javadoc)
  @see net.timewalker.ffmq4.storage.data.impl.AbstractBlockBasedDataStore#extendStoreFiles(int, int)