I'm out of ideas

Question about the task

Prices 2

Java Core, Level 8, Lesson 11

Under discussion

The code works on my pc but it always fails the validaton. Any idea where could be the mistake?

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

The program runs with one of the following sets of arguments:
-u id productName price quantity
-d id

Argument values:
where id is 8 characters
productName is 30 characters
price is 8 characters
quantity is 4 characters
-u updates the data for the product with the specified id
-d performs the physical deletion of the product with the specified id (all data related to the passed id)

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

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.
When you run the program without arguments, the product list must remain unchanged.
When the program is started with the arguments "-u id productName price quantity", the product information in the file should be updated.
When the program is started with the arguments "-d id", the line for the product with the specified id should be removed from the file.
The file streams must be closed.

package com.codegym.task.task18.task1828; /* Prices 2 */ import java.io.*; import java.util.ArrayList; public class Solution { public static void main(String[] args) { try { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String fileName = reader.readLine(); if(args.length == 0) return; if(args[0].equals("-u")) { String id = args[1]; String productName = args[2]; String price = args[3]; String quantity = args[4]; ArrayList<String> list = new ArrayList<>(); String line; BufferedReader fileReader = new BufferedReader(new FileReader(fileName)); while((line = fileReader.readLine()) != null) list.add(line); fileReader.close(); for(int i = 0; i < list.size(); i++) { if(list.get(i).substring(0,8).trim().equals(id)){ line = String.format("%-8s%-30s%-8s%-4s", id, productName, price, quantity); list.set(i, line); } } BufferedWriter fileWriter = new BufferedWriter(new FileWriter(fileName)); for(int i = 0; i < list.size(); i++) { fileWriter.write(list.get(i)); if(i < (list.size() -1)) fileWriter.newLine(); } fileWriter.close(); } if(args[0].equals("-d")) { String id = args[1]; ArrayList<String> list = new ArrayList<>(); String line; BufferedReader fileReader = new BufferedReader(new FileReader(fileName)); while((line = fileReader.readLine()) != null) list.add(line); fileReader.close(); BufferedWriter fileWriter = new BufferedWriter(new FileWriter(fileName)); for(int i = 0; i < list.size(); i++) { if(list.get(i).substring(0, 8).trim().equals(id)) continue; fileWriter.write(list.get(i)); if(i < (list.size()) -1) fileWriter.newLine(); } fileWriter.close(); } } catch (IOException e) { } } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

12 January 2022, 16:42

My guess would be where the conditions say: "Argument values: where id is 8 characters productName is 30 characters price is 8 characters quantity is 4 characters" If the argument is 8 characters then line 32 and 58, after trimming the id in the list, would not equal the id from arguments. Example: The String "42 " does not equal the String "42"

Rho366

Level 20 , Guatemala City, Guatemala

20 January 2022, 15:44

Thanks for the answer, i updated the program to trim both the id in the list and the id in the arguments but i still unable to pass the test. I'm trying to rewrite the program with another solution.

Guadalupe Gagnon

Level 37 , Tampa, United States

20 January 2022, 16:33

The logic that I would use for this task: - read lines from file and save to list - find the item in the list that has the same id from args[1] and remove that item - if args[0] is "-u" then put the new line in with the rest of the args at the same spot the line was removed - write all the items in list back to the file reading all the lines and saving them, removing the line with the same id, and writing all the lines back to the file will need to happen in the program regardless of what args[0] is. The only thing that changes in this task is that it should add the new line back into the list if args[0] is "-u". You can simplify the program quite a bit by not repeating the same logic in different "if - else if" blocks.

Guadalupe Gagnon

Level 37 , Tampa, United States

20 January 2022, 17:04

(unless, of course, that the args array is empty or args[0] isn't "-u" or "-d")