Question

Write a Java Program that reads the following:

Ask the user for a balance. From the accounts.dat file, display all the accounts that have a balance of at least what the user entered.

accounts.dat is a binary file. Each entry contains a credit card number (long), a balance (double), and a cash back flag (boolean).

Question 1 10 points Ask the user for a balance. From the accounts.dat file.display all the accounts that have a balance of at least what the user entered. accounts.dat is a binary file. Each entry contains a credit card number (long), a balance (double), and a cash back flag (boolean). View required output Test Case 1 Standard Input Files in the same directory Seee • accounts.dat Enter a balance Accounts with a balance of at least $9000.00\n Card Number Balance Cash Back? 201715141501700 9135.90 Yes 4508271490627227 9890.51 No 3573877643495486 9985.21 No 5100172198301454 9315.15 3551244602153760 9409.97 Yes 4405942746261912 9869.27 Non 305261106120159866.30 Non 7 results in NO Test Case 2

Answer 1

Idea is long =8byte in length
double is 8 byte in length
boolean is 1bit in length

package HomeworkLib.job;
import javax.xml.transform.stream.StreamSource;
import java.io.*;
import java.util.Arrays;
import java.util.Scanner;

public class BinaryFile {
    private static final int BUFFER_SIZE = 16; // 4KB

    public static void main(String[] args){
        double balance;
        System.out.println("Enter a balance");
        Scanner in;
        in = new Scanner(System.in);
        balance =in.nextDouble();
        try (
                ObjectInputStream inputStream = new ObjectInputStream(new FileInputStream(inputFile);
        ) {

            int byteRead;
            String creditCardNumber;
            double cardBalance;
            boolean cashbackFlag;
            byte[] buffer = new byte[BUFFER_SIZE];
            while (inputStream.read(buffer) != -1) {
                creditCardNumber =new String(buffer, 0, 8);
                cardBalance =Double.parseDouble(new String(buffer, 8, 8));
                cashbackFlag =inputStream.readBoolean();
                if(cardBalance>=balance){
                    String flag =cashbackFlag?"Yes":"No";
                    System.out.println(creditCardNumber +"\t"+cardBalance +"\t "+flag);
                }
            }

        } catch (IOException ex) {
            ex.printStackTrace();
        }

    }
}