1) Magic Cookie: I am hardcoding the magic cookie value to 259 since the give data file has that value. Everytime I read the header file, I am checking that cook is 259. If the value is not 259, I throw new IOException(). Is that right?
2) 1 byte flag. 00 implies valid record, 0xFF implies deleted record. When I read the file, that field has 0 value not 00. what is 0xFF? Is it a hexadecimal number? Am a storing hex when the record gets deleted. Right now, I have flag as type byte in my data object. I am not sure if I just make this field string and store "0xff" as a string value.