class GroupedRandomAccessSource implements RandomAccessSource {

	public int get(long position) throws IOException {
		SourceEntry entry = getSourceEntryForOffset(position);
		
        if (entry == null) // we have run out of data to read from
        	return -1;
        
        return entry.source.get(entry.offsetN(position));

	}

	public  GroupedRandomAccessSource(RandomAccessSource[] sources);

}