internal const int RESERVED_INDEX = 12; // 12-31 /** * 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 */ internal DBFHeader(java.io.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 = (int)(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()); } }
/** * Reading a column definition from file<br> * @param ff file handle (correctly positioned) * @param iCol index starts with 1 * @param locn offset to the current column * @return struct with column info */ internal static TsColumn readColdef(java.io.RandomAccessFile ff, String tableName, int iCol, int locn) //throws tinySQLException { try { // seek the position of the field definition data. // This information appears after the first 32 byte // table information, and lives in 32 byte chunks. // ff.seek((iCol - 1) * 32 + 32); // get the column name into a byte array // byte[] b = new byte[11]; ff.readFully(b); // convert the byte array to a String // Seek first 0x00 occurence and strip array after that // // some C-implementations do not set the remaining bytes // after the name to 0x00, so we have to correct this. //bool clear = false; int i = 0; while ((i < 11) && (b[i] != 0)) { i++; } while (i < 11) { b[i] = 0; i++; } String colName = (new java.lang.StringJ(b, Utils.encode)).trim(); // read in the column type which follows the 11 byte column name // byte[] c = new byte[1]; c[0] = ff.readByte(); String ftyp = new java.lang.StringJ(c, Utils.encode); // skip four bytes // ff.skipBytes(4); // get field length and precision which are in the two bytes following // the column type. // short flen = Utils.fixByte(ff.readByte()); // 16 short fdec = Utils.fixByte(ff.readByte()); // 17 if (ftyp.equals("N") & fdec == 0) { ftyp = "I"; } // bytes 18 - 31 are reserved // create a new tsColumn object and assign it the // attributes of the current field // if (TinySQLGlobals.DEBUG) { java.lang.SystemJ.outJ.println("Try and create tsColumn for " + colName); } TsColumn column = new TsColumn(colName); /* * The column type is now given as java.sql.Types constant */ column.type = typeToSQLType(ftyp); column.size = flen; column.decimalPlaces = fdec; column.position = locn + 1; // set the field position to the current column.tableName = tableName; return(column); } catch (Exception e) { throw new TinySQLException(e.getMessage()); } }