Task verification throwing error

Question about the task

Prices

Java Core, Level 8, Lesson 11

Under discussion

CrUD for a table inside a file.
Read a file name for CrUD operations from the console.

The program is started with the following arguments:
-c productName price quantity

Argument values:
where id is 8 characters.
productName is 30 characters.
price is 8 characters.
quantity is 4 characters.
-c adds the product with the specified parameters to the end of the file, and generates an id by incrementing the maximum id found in the file.

The file data is stored in the following order (without separating spaces):
id productName price quantity

Each data field is padded with spaces up to its length.

Before adding a new line, re-write all of its contents to the file.

Example:
19847 Swim trunks, blue 159.00 12 198479 Swim trunks, black with printe173.00 17 19847983Snowboard jacket with reflecti10173.991234

Requirements:

The program should read a file name for CrUD operations from the console.
The Solution class should not use static variables.
When you run the program without arguments, the product list must remain unchanged.
When the program is run with the arguments "-c productName price quantity", a new line with the corresponding product should be added to the end of the file.
The product must have the next id after the maximum id found in the file.
The format of the new product line must precisely match that format specified in the task.
The file streams must be closed.

package com.codegym.task.task18.task1827; /* Prices */ import java.util.Scanner; import java.io.*; public class Solution { public static void main(String[] args) throws Exception { Scanner scan = new Scanner(System.in); String fileName = scan.nextLine(); FileInputStream inputStream = new FileInputStream(fileName); InputStreamReader in = new InputStreamReader(inputStream); BufferedReader reader = new BufferedReader(in); int id = 0; String currentline = ""; while ((currentline = reader.readLine()) != null) { String[] temp = currentline.split(" "); int d = Integer.parseInt(temp[0]); if (d > id) id = d; } reader.close(); inputStream.close(); //String insert = ""; if(args[0].equals("-c")) { id = id + 1; String productName = args[1]; double price = Double.parseDouble(args[2]); int quantity = Integer.parseInt(args[3]); //String insert = id + " " + productName + " " + price + " " + quantity; String insert = String.format("%-8s%-30s%-8s%-4s",id,productName,price,quantity); // FileOutputStream outputStream = new FileOutputStream(fileName); //outputStream.write(buffer); //outputStream.write('\n'); //outputStream.write(insert.getBytes()); PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter(fileName, true))); out.println(insert); out.close(); //outputStream.close(); } } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

17 October 2019, 19:33

The big problem that I see is the way that you are getting the max id:

while ((currentline = reader.readLine()) != null) {
            String[] temp = currentline.split(" "); // this line in particular
            int d = Integer.parseInt(temp[0]);
            if (d > id)
                id = d;
        }

You are attempting to split the line read in and assume that the String at index 0 is the ID. The problem is that if the id is a full 8 digits then then it won't split until the first split in the product description. For example: this line: 19847983Snowboard jacket with reflecti10173.991234 would split like this: [{19847983Snowboard}, {jacket}, {with}, {reflecti10173.991234}] and if you tried to parse the first index it would throw an error. You didn't close the InputStreamReader (in) either.