/* * Creates 20 random integers (1-50) then writes them to a file. * Then it reads the file, and outputs them. */import java.util.*;import java.io.*;public class Program8{ public static void main(String[] args) { // Create a RNG, and an byte array. Random gen = new Random(); byte[] matrix = new byte[20]; // Creates a file, then has it setup to be removed on exit // and creates the actual file. File f = new File("data.bin"); try { f.deleteOnExit(); f.createNewFile(); } catch(IOException e) { System.out.println(e.getMessage()); } try { // create a file output stream for File f FileOutputStream out = new FileOutputStream(f); System.out.println("WRITING DATA TO FILE ("+ f.getName() +"):"); for (int x=0; x<20; x++) { // store each integer as a byte // then display byte as integer matrix[x] = (byte)(1+gen.nextInt(50)); System.out.print((int)matrix[x] + " "); } try { // write out the byte information to the file for (int x=0; x<matrix.length;x++) { out.write(matrix[x]); } } catch(IOException e) { System.out.println(e.getMessage()); } } catch(FileNotFoundException e) { System.out.println(e.getMessage()); } System.out.println(); try { // create a file input stream for File f FileInputStream in = new FileInputStream(f); System.out.println("READING DATA FROM FILE ("+ f.getName() +"):"); try { for (int x=0;x<20;x++) { // read in one byte from file // then display each as integer System.out.print((int)(in.read()) + " "); } } catch(IOException e) { System.out.println(e.getMessage()); } } catch(FileNotFoundException e) { System.out.println(e.getMessage()); } }}