The code seems to be working fine when I test it, and I get a weird validation error : "The file output stream was not closed", while I'm quite sure I properly closed it. Does anyone understand ?

Question about the task

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Hello everyone, I think the code is working properly (at least I think my testing went fine according to the specs in condition.tcs, however the task is to being validated and I get the following error : The file streams must be closed. (Recommendation from your mentor : the file output stream was not closed), while I close it at line 80. Does anyone understand what I'm doing wrong here ? Thanks in advance, Earil

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.*; import java.io.*; public class Solution { public static void main(String[] args) throws Exception { //Reading file name and opening input and output streams BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String fileName = reader.readLine(); Scanner scanner = new Scanner(new FileInputStream(fileName)); BufferedOutputStream outputStream = new BufferedOutputStream(new FileOutputStream(fileName, true)); reader.close(); if(args[0].equals("-c")){ //find the maximum ID in the file int maxID = 0; while(scanner.hasNext()){ String line = scanner.nextLine(); String id = line.substring(0, 8); id = id.substring(0, id.indexOf(" ")); int intID = Integer.parseInt(id); if(intID > maxID){ maxID = intID; } } //increment it to get the ID of the new product maxID++; //turn it into a string and add spaces to get to 8 characters String newID = maxID + ""; while(newID.length() < 8){ newID += " "; } //Make the other arguments the correct number of characters String productName = args[1]; String price = args[2]; String quantity = args[3]; while(productName.length() < 30){ productName += " "; } while (price.length() < 8){ price += " "; } while (quantity.length() < 4) { quantity += " "; } //Append the new line to the file outputStream.write(System.lineSeparator().getBytes()); outputStream.write(newID.getBytes()); outputStream.write(productName.getBytes()); outputStream.write(price.getBytes()); outputStream.write(quantity.getBytes()); } //Close the streams scanner.close(); outputStream.close(); } }

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BTu4-man

Level 1

2 July 2019, 21:00

solution

Hi there. There are many reasons for getting such error message "file stream is not closed", and one of them, abnormal closing of the program with an exception (without using try with resources block). So program shut down in emergency, and #80 line just not happens to be executed. I run your program, and it throws exceptions:

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: begin 0, end -1, length 8

for line 30

id = id.substring(0, id.indexOf(" "));

I guess because of 3rd line:

19847   Swim trunks, blue             159.00  12
198479  Swim trunks, black with printe173.00  17
19847983Snowboard jacket with reflecti10173.99

Also, look at this condition: When you run the program without arguments, the product list must remain unchanged. When I tried to run, again got Exception, because of next line:

if(args[0].equals("-c")){

So please read conditions carefully once more, and give your code good testing.

Earil

Level 25 , Paris, France

4 July 2019, 13:32

Thanks you so much for your help ! I was able to add minimal changes to the code that made it work properly !!! I had absolutely not seen the problem with my id.substring and I had not idea it would cause an exception. My bad for not properly testing all the cases, I will pay more careful attention to that in the future. Again, thanks a lot for your help and your consideration.