S9P2

Write a program which generates random integers and stores them in a file named “rand.dat”. The program then reads the integers from the file and displays on the screen.

Code:

 import java.io.*;  
 import java.util.*;  
 class S9P2_Random  
 {  
      public static void main(String args[])  
      {  
           FileWriter FW = null;  
           BufferedWriter bfwr = null;  
           File inFile = new File("rand.dat");  
           try  
           {  
                int rand_int;  
                FW = new FileWriter(inFile);  
                bfwr = new BufferedWriter(FW);  
                Random generate_rand = new Random();  
                System.out.println("\nGenerating & Storing Random integers from 0 to 99..\n");  
                for(int i=0; i<10; i++)  
                {  
                     rand_int = generate_rand.nextInt(100);  
                     System.out.print(rand_int+"\t");  
                     bfwr.write(rand_int+"\r\n");  
                }  
           }  
           catch(IOException e)  
           {  
                System.out.println(e.getMessage());  
           }  
           finally  
           {  
                try  
                {  
                     bfwr.close();  
                }  
                catch(IOException e){ }  
           }  
           try  
           {  
                System.out.println("\nRetrieving Random integers stored in file 'rand.dat'..");  
                Scanner scanner = new Scanner(inFile);  
                while(scanner.hasNextInt())  
                {  
                     System.out.println(scanner.nextInt()+"\t");  
                }  
           }  
           catch(NullPointerException e)  
           {  
                System.out.println(e.getMessage());  
           }  
           catch(FileNotFoundException e)  
           {  
                System.out.println(e.getMessage());  
           }            
      }  
 }  

Output: