Could someone explain to me the following?

Question about the task

Under discussion

I understand what the task requires, however, I am not clear in the steps I should follow to convert the byte data to find the id and display the required information - as you can see from my code. For example, int data = inputStream.read(); is going to give me bytes. It does not give me lines, characters, strings or integers. So should I turn the inputStream as a string? Break it into lines (what would be character that denotes the end of the line)? So how do I get an inputStream into lines and how it knows it is a line? Does it have at the end of each line a return carriage? One thing I can do is to change the int id into a byte, find it as a byte, but how do I display the rest of the elements in that line? I hope you understand my confusion. Thanks for your help!

Read a file name from the console.
Search the file for information related to the specified id. Display it in the format used in the file.
The program is started with one argument: id (an int).
Close the streams.

The file data is separated by spaces and stored in the following order:
id productName price quantity
where id is an int
productName is a String — it can contain spaces
price is a double
quantity is an int

The information for each product is stored on a separate line.

Requirements:

The program should read a file name from the console.
Create an input stream for the file.
The program should search the file and display information related to the specified id passed as the first argument.
The stream used to read the file must be closed.

package com.codegym.task.task18.task1822; /* Finding data inside a file */ import java.io.BufferedReader; import java.io.FileInputStream; import java.io.InputStreamReader; public class Solution { public static void main(String[] args) { int id = Integer.parseInt(args[0]); try { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String fileName = reader.readLine(); FileInputStream inputStream = new FileInputStream(fileName); while(inputStream.available()>0){ int data = inputStream.read(); if(data == id){ System.out.println(data); } } inputStream.close(); }catch(Exception e){ e.printStackTrace(); } } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

15 November 2019, 14:45

public static void main(String[] args) {
  int id = Integer.parseInt(args[0]);

  try {
    BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
    String fileName = reader.readLine();

    FileInputStream inputStream = new FileInputStream(fileName);

    // create a buffer. setting it to IS.available() will set it to the exact length of total bytes
    byte[] data = new byte[inputStream.available()];

    // use the buffer. This will fill the buffer with bytes until full or all bytes have been read
    inputStream.read(data);

    // This converts all those bytes into a readable string. It will include
    String fileData = new String(data);

    System.out.println(fileData);

    // finish the task below ↓↓↓

    inputStream.close();
  }catch(Exception e){
    e.printStackTrace();
  }

}