Question

Java

Write an application using the FileInputStream that OPENS a file which contains the name of the user's favorite book and then DISPLAYS it to the user. IF the file does not exist, PROMPT the user for the book's title, and then WRITE it to the file by using a FileOutputStream. Save the file as BookApplication.java.

Answer 1

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Scanner;

public class BookApplication {

   public static void main(String[] args) {
       // TODO Auto-generated method stub
       Scanner sc=new Scanner(System.in);
       try{
               File f = new File("book.txt");//to check if file exists or not
               if(!f.exists()){//if file doesn't exist create a new one and ask user for book name and write to it
                   f.createNewFile();
       OutputStream outputStream = new FileOutputStream("book.txt");
               System.out.println("Enter favorite book");
               String bookname=sc.nextLine();
               outputStream.write(bookname.getBytes());
               }else{//if file exists read book name from the file and display to user
           InputStream inputStream = new FileInputStream("book.txt");
           int ch;
           while((ch=inputStream.read())!=-1)
           System.out.print((char)ch);
               }
      
      
       } catch (IOException ex) {
       ex.printStackTrace();
       }

   }

}

Expected output:

when file doesn't exist the output will be

After writing data to file when file exists output will be