Question

Write a program to perform the following actions: the language is Java

– Open an output file named “Assign14Numbers.txt”

– Using a do-while loop, prompt the user for and input a count of the number of random integers to produce, make sure the value is between 35 and 150, inclusive.

– After obtaining a good count, use a for-loop to generate the random integers in the range 0 ... 99, inclusive, and output each to the file as it is generated with one integer per line (no extra spaces, tabs, or lines).

– Close output file – open and view it in the IDE editor if desired.

– In program, add code to reopen the same file for input.

– Using an EOF while-loop to detect the end of data, input and display all data items from the file formatted as stated in the next instruction – do NOT use a counting loop to input the data!

– Display the random integers from the file to the console with 15 numbers per line formatted with right-alignment in columns that are exactly 4 positions wide, there must be exactly 1 blank line above and below the numbers displayed on the console.

– Close the input file.

Answer 1

Complete code in java:-

import java.util.*;
import java.io.*;

class random {
   public static void main(String ... args) {
       // Creating scanner object to take input from an input stream.
       Scanner sc = new Scanner(System.in);
       // Creating Random object to generate random numbers.
       Random rand = new Random();
       int count;
       // Opening file to write into.
       try {
           FileWriter fw = new FileWriter("Assign14Numbers.txt");
           // Taking number of numbers that will be printed intot he opened file.
           do {
               System.out.print("Enter a number in range 35-150 (inclusive) : ");
               count = sc.nextInt();
           }while(count < 35 || count > 150);
           // Generating random numbers and writting them into file.
           for(int i = 0; i < count; i++) {
               int num = rand.nextInt(100);
               fw.write(num+"\n");
           }
           // Closing file.
           fw.close();
       } catch (IOException e) {
           System.out.println("IO Error has occured, try again...");
       }
       // Again opening file into read mode, to read from
       try {
           // Creating Input stream object for file.
           FileInputStream fr = new FileInputStream("Assign14Numbers.txt");
           // Creating scanner object to read from file stream stream
           sc = new Scanner(fr);
           // Count will keep track the number of numbers to be printed in a line, specified 15.
           count = 0;
           // Printing formatted data.
           System.out.println();
           String output = "";
           // Readin from file until end of file (EOF).
           while(sc.hasNextLine()) {
               if(count == 15) {
                   System.out.printf("%s\n", output);
                   output = "";
                   count = 0;
               }
               // I am using tab "\t" to make columns 4 position wide,
               // because "\t" is equal to 4 spaces.
               output += ("\t"+sc.nextLine());
               count++;
           }
           System.out.printf("%s\n\n", output);
           sc.close();
       } catch (IOException e) {
           System.out.println("IO Error has occured try again...");
       }
   }
}

Screenshot of output:-