Output seems fine when testing.. can't seem to pass

Question about the task

Rounding numbers

Java Core, Level 8, Lesson 11

Under discussion

I've had a really good look through other solutions. A number of variations that I can't wrap my head around.

Read 2 file names from the console.
The first file contains real (fractional) numbers, separated by spaces. For example, 3.1415.
Round the numbers to integers and write them, separated by spaces, to the second file.
Close the streams.

The rounding should work like this:
3.49 => 3
3.50 => 4
3.51 => 4
-3.49 => -3
-3.50 => -3
-3.51 => -4

Requirements:

The program should read a file name twice from the console.
Create an input stream for the first file. Create an output stream for the second file.
Read the numbers from the first file, round them, and write them to the second file, separated by spaces.
The rounding must be performed as indicated in the task.
The file streams must be closed.

package com.codegym.task.task18.task1820; /* Rounding numbers */ import java.io.*; import java.sql.SQLOutput; import java.util.ArrayList; import java.util.Scanner; import java.util.jar.JarOutputStream; public class Solution { public static void main(String[] args) throws IOException { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String filename1 = reader.readLine(); String filename2 = reader.readLine(); FileInputStream inputStream = new FileInputStream(filename1); FileOutputStream outputStream = new FileOutputStream(filename2); //FileInputStream inputStream = new FileInputStream("C:\\Users\\Angus\\Desktop\\Temp\\data.txt"); //FileOutputStream outputStream = new FileOutputStream("C:\\Users\\Angus\\Desktop\\Temp\\result.txt"); // convert inputStream to array byte[] buffer = new byte[inputStream.available()]; inputStream.read(buffer); // convert byte array to string String str = new String(buffer); // System.out.println(str); // remove spaces from string and convert to array String[] strArray = str.split(" "); // Convert strArray values to doubles. ArrayList<Byte> dubs = new ArrayList<>(); for (String s : strArray) { dubs.add((byte) Math.round(Double.parseDouble(s))); } // convert arraylist to byte array for writing to file. byte[] b = dubs.toString().getBytes(); outputStream.write(b); reader.close(); inputStream.close(); outputStream.close(); } }

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Juan Ma

Level 41 , Arauca, Colombia

14 June 2020, 06:36

The problem is that you are writing a list in file2. Your output: [#, #, #, #] Required output: # # # # The shortest change in your code could be the use of replaceAll on line 44, erasing the characters "[" "]" "," using regex. Example: byte[] b = dubs.toString().replaceAll("[\\[\\]\\,]","").getBytes();

Angus McDonald

Level 5 , Sydney, Australia

Expert

15 June 2020, 09:58

Thanks Juan. If the problem is in file2 (did you mean byte[] b ?) then I think I should go back to line 31 where I have created the String and re-write everything below. I've tried the below.. which again outputs the correctly rounded numbers and writes them to file.. however it's not passing.. Is it because I'm using a PrintStream not an OutputStream?

public static void main(String[] args) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        String filename1 = reader.readLine();
        String filename2 = reader.readLine();

        FileInputStream inputStream = new FileInputStream(filename1);
        PrintStream outputStream = new PrintStream(filename2);

        //FileInputStream inputStream = new FileInputStream("C:\\Users\\Angus\\Desktop\\Temp\\data.txt");
        //PrintStream outputStream = new PrintStream("C:\\Users\\Angus\\Desktop\\Temp\\result.txt");

        // convert inputStream to array
        byte[] buffer = new byte[inputStream.available()];
        inputStream.read(buffer);

        // convert byte array to string
        String str = new String(buffer);

        // split string values into a String array
        String[] results = str.split("\\n");

        // convert strings array into rounded int array
        Integer[] ints = new Integer[results.length];
        for (int i = 0; i < results.length; i++) {
            ints[i] = Math.toIntExact(Math.round(Double.parseDouble(results[i])));
            outputStream.printf(ints[i] + " ");
        }

        reader.close();
        inputStream.close();
        outputStream.close();
    }

Juan Ma

Level 41 , Arauca, Colombia

16 June 2020, 09:23

Hi Angus, I meant "dubs", it is an ArrayList whose format, as string, is what I wrote you above: [#, #, #, #], so you are writing an ArrayList in file2(file to copy) . With replaceAll you can remove characters "[" "]" "," Just change the line 44 to: byte[] b = dubs.toString().replaceAll("[\\[\\]\\,]","").getBytes();

KIN SOCHEAT

Level 34 , Phnom Penh, Cambogia

11 June 2020, 01:41

ArrayList<Byte> dubs = new ArrayList<>(); for (String s : strArray) { dubs.add((byte) Math.round(Double.parseDouble(s))); } ------------ String st; for (String s : strArray) { st =((byte) Math.round(Double.parseDouble(s))) + " "; } -----------also-------- /* BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String filename1 = reader.readLine(); String filename2 = reader.readLine(); FileInputStream inputStream = new FileInputStream(filename1); FileOutputStream outputStream = new FileOutputStream(filename2); */ FileInputStream inputStream = new FileInputStream("C:\\Users\\Angus\\Desktop\\Temp\\data.txt"); FileOutputStream outputStream = new FileOutputStream("C:\\Users\\Angus\\Desktop\\Temp\\result.txt"); ---- I remember have one ex they write ready from consul but real not...so first try this...

Angus McDonald

Level 5 , Sydney, Australia

Expert

11 June 2020, 07:58

Thanks for the help Kin. I've had a quick look however could quite get it. I'm now getting an exception throw which I don't have the patience to work through. I'll revisit this at a later date. Thanks again!

KIN SOCHEAT

Level 34 , Phnom Penh, Cambogia

9 June 2020, 13:09

[3, 4, 4, -3, -3, -4] your result 3 4 4 -3 -3 -4 try use string instate of array

Angus McDonald

Level 5 , Sydney, Australia

Expert

10 June 2020, 08:30

Right ok. I'm not sure how to..which seems silly because I've worked with strings a lot in this course. At which step in my code should I convert to string and write to file?