| 0,0 → 1,57 |
|---|
| // WARNING: This program uses the Assertion class. When it is run, |
| // assertions must be turned on. For example, under Linux, use: |
| // java -ea Genfile |
| |
| /** Generate a data file. The size is a multiple of 4096 bytes. |
| The records are short ints, with each record having a value |
| less than 30,000. |
| */ |
| |
| import java.io.*; |
| import java.util.*; |
| import java.math.*; |
| |
| public class Genfile2 { |
| |
| static final int BlockSize = 4096; |
| static final int NumRecs = 2048; // Because they are short ints |
| |
| /** Initialize the random variable */ |
| static private Random value = new Random(); // Hold the Random class object |
| |
| static int random(int n) { |
| return Math.abs(value.nextInt()) % n; |
| } |
| |
| public static void main(String args[]) throws IOException { |
| |
| assert (args.length == 3) && (args[0].charAt(0) == '-') : |
| "\nUsage: Genfile <option> <filename> <size>" + |
| "\nOptions ust be '-a' for ASCII, or '-b' for binary." + |
| "\nSize is measured in blocks of 4096 bytes"; |
| |
| int filesize = Integer.parseInt(args[2]); // Size of file in blocks |
| DataOutputStream file = new DataOutputStream( |
| new BufferedOutputStream(new FileOutputStream(args[1]))); |
| |
| int recs = NumRecs * filesize; |
| |
| if (args[0].charAt(1) == 'b') // Write out random numbers |
| for (int i=0; i<filesize; i++) |
| for (int j=0; j<NumRecs; j++) { |
| short val = (short)(random(29999) + 1); |
| file.writeShort(val); |
| } |
| else if (args[0].charAt(1) == 'a') // Write out ASCII-readable values |
| for (int i=0; i<filesize; i++) |
| for (int j=0; j<NumRecs; j++) { |
| short val = (short)((8224 << 16) + random(26) + 0x2041); |
| file.writeShort(val); |
| } |
| else assert false : "Bad parameters"; |
| |
| file.flush(); |
| file.close(); |
| } |
| |
| } |