/**
* Constructs a DBFHeader, read the data from file <br>
* You need to supply an open file handle to read from
*
* @param ff open file handle for read access
*/
DBFHeader(RandomAccessFile ff) throws tinySQLException {
try {
ff.seek(FLAG_INDEX);
file_type = Utils.fixByte(ff.readByte());
// get the last update date
file_update_year = Utils.fixByte(ff.readByte());
file_update_month = Utils.fixByte(ff.readByte());
file_update_day = Utils.fixByte(ff.readByte());
// a byte array to hold little-endian long data
//
byte[] b = new byte[4];
// read that baby in...
//
ff.readFully(b);
// convert the byte array into a long (really a double)
// 4-7 number of records
numRecords = (int) Utils.vax_to_long(b);
// a byte array to hold little-endian short data
//
b = new byte[2];
// get the data position (where it starts in the file)
// 8-9 Length of header
ff.readFully(b);
headerLength = Utils.vax_to_short(b);
// find out the length of the data portion
// 10-11 Length of Record
ff.readFully(b);
recordLength = Utils.vax_to_short(b);
// calculate the number of fields
//
numFields = (headerLength - 33) / 32;
// skip the next 20 bytes - looks like this is not needed...
// ff.skipBytes(20);
// 12-31 reserved
Utils.log("HEADER=" + this.toString());
} catch (Exception e) {
throw new tinySQLException(e.getMessage());
}
}
