limit = FIRST_RECORD_POSITION;
out.putLong(LIMIT_POSITION,limit);
out.putLong(EARLIEST_POSITION,earliestTimestamp);
out.putLong(LATEST_POSITION,latestTimestamp);
out.position(FIRST_RECORD_POSITION);
bostr = new ByteBufferOutputStream(out);
output = new Output(bostr);
} else {
memoryMappedFile = new RandomAccessFile(file,"r");
fileSize = (int)file.length();
MappedByteBuffer bb = memoryMappedFile.getChannel().map(MapMode.READ_ONLY, 0, HEADER_END);