How to append new line in an existing file?

Question

How am I supposed to append a new line after I finish adding what I am supposed to. I have the following code:

        try{
            String textToAppend = question+userInput+","+typeOfAnswer;
            Files.write(Paths.get("save.txt"), textToAppend.getBytes(), StandardOpenOption.APPEND);
        }
        catch (NoSuchFileException e){

        }
        catch(IOException e){

        }

Example: question: By what initials was Franklin Roosevelt better known? userInput: RED typeOfAnswer will be wrong: wrong

I get my question and real answer from a file, then I compare the real answer with the userInput and see whether the typeOfAnswer si wrong/right. I want to output the question, userInput and typeOfAnswer in a File but I have multiple questions, hence I want to output the final results each on a new line.

@EmreSavcı I'm not getting any exceptions but if I try let's say to create the textToAppend like this: `textToAppend = "\n"+question+userInput+","+typeOfAnswer` I won't get the new information in a new line. — Ryk, Nov 28 '18 at 20:28
@Andreas tried..i have the same problem..i get sth like this: `By what initials was Franklin Roosevelt better known?RED,wrongWhich number president was Franklin Roosevelt?RED,wrong`. There is no separation between wrong and Which — Ryk, Nov 28 '18 at 20:30
@Ryk Are you on Windows, using Notepad to show file content? If so, then be aware that Notepad doesn't recognize `\n` as an end-of-line marker. Only `\r\n`. — Andreas, Nov 28 '18 at 20:31
@GBlodgett That's not my problem tho' :)...it is not a duplication. Read again. — Ryk, Nov 28 '18 at 20:31
What your variables question, userInput and typeOfAnswer contains? — Emre Savcı, Nov 28 '18 at 20:32
Please provide [Minimal, Complete, and Verifiable example](https://stackoverflow.com/help/mcve), because simply adding `System.lineSeparator()` at the of text before writing it should work. — Andreas, Nov 28 '18 at 20:32

score 3 · Accepted Answer · answered Nov 28 '18 at 20:38

As commented:

textToAppend += System.lineSeparator();

Proof

import java.nio.file.*;

public class Test {
    public static void main(String[] args) throws Exception {
        save("By what initials was Franklin Roosevelt better known?", "RED", "wrong");
        save("Which number president was Franklin Roosevelt?", "RED", "wrong");
    }
    public static void save(String question, String userInput, String typeOfAnswer) throws Exception {
        String textToAppend = question + userInput + "," + typeOfAnswer;
        textToAppend += System.lineSeparator();
        Files.write(Paths.get("save.txt"), textToAppend.getBytes(), StandardOpenOption.APPEND, StandardOpenOption.CREATE);
    }
}

File Content

By what initials was Franklin Roosevelt better known?RED,wrong
Which number president was Franklin Roosevelt?RED,wrong

File Content after running program 3 times

By what initials was Franklin Roosevelt better known?RED,wrong
Which number president was Franklin Roosevelt?RED,wrong
By what initials was Franklin Roosevelt better known?RED,wrong
Which number president was Franklin Roosevelt?RED,wrong
By what initials was Franklin Roosevelt better known?RED,wrong
Which number president was Franklin Roosevelt?RED,wrong

What if my file already exists? Do I have to put StandardOpenOption.Create? — Ryk, Nov 28 '18 at 20:40
`StandardOpenOption.CREATE` means that it will create the file *if* it doesn't exist. — Andreas, Nov 28 '18 at 20:42

How to append new line in an existing file?

1 Answers1