Python dev crying for help over reading file into array

[jagged sinew]

How do I read a file into an array with Java using only the Scanner class? I'm not given the length of the file and am only allowed to use the Scanner class for this task, no more modern APIs or anything.

// load in file lines/content into array
    public static String[] loadFile(String fname) {
        Scanner fileIn = null;
        
        try {
            fileIn = new Scanner(new File(fname));
        } catch (FileNotFoundException e) {
            String[] emptyArr = new String[0];
            return emptyArr;
        }
        
        int lineCount = 0;
        
        while(fileIn.hasNextLine()) {
            lineCount++;
            fileIn.nextLine();
        }
        
        String[] fileContent = new String[lineCount];
        
        
        
        fileIn.close();
        return fileContent;
    }``` This is all I have so far, not sure if this is down the right path

[exotic lake]

Hey, @jagged sinew!
Please remember to /close this post once your question has been answered!

[sharp briar]

The idea would be to use an ArrayList, not an array

[jagged sinew]

yeah here's teh thing ive learned arraylists before but

school cs is stupid

and they wont let me use it until we cover it

@sharp briar im forced to use a normal array for school purposes

😭

bruh if i show my school teacher some ml/ai shit hes gonna know whos the boss

oh well

[sharp briar]

I don't know what to tell you. Store the file in an array of size 50000 or something

Then copy it over to an array of the exact right size

[jagged sinew]

he told us we couldnt do that 😦

yeah again school cs is new levels of stupid

[sharp briar]

Maybe they just want you to redo ArrayList

[jagged sinew]

not sure

[sharp briar]

Start with an array of size 1. If the array is ever too small, copy it over to a newly created array of double the size

[jagged sinew]

to copy a line i would just do arr[0] = fileIn.nextLine() right?

[sharp briar]

What? No you're finished reading the file

[jagged sinew]

right

but in the loop

i kinda dumb u see

[sharp briar]

Were you not a Python dev?

[jagged sinew]

i am but uhh id ont pay attention in class for java

[sharp briar]

It doesn't matter. Reading a file is reading a file

[jagged sinew]

alr

yeah i mean im assuming he doesnt want us to implement arraylist manually

since we shouldnt "know what that is"

[sharp briar]

But it's possible to be clever enough to realize that when an array isn't big enough, you could make a bigger array and copying over

[jagged sinew]

that's true

[sharp briar]

Anyway, I wasn't in your class so I can't guess what was the vibe of what is allowed, what isn't, and what they thought you could figure out

[jagged sinew]

gotcha

alr ill just do the large array trick

willing to sacrifice a bit of my grade for good code

even if the teacher doesnt agree

[vague maple]

well

you could just do it without a buffer

1. Read the entire file into one string variable
2. Split the var by your separator
3. Return the result

[woven kindle]

Kinda stupid

Arraylist literally better

[vague maple]

Arrays are always more efficient if you know the fixed size

Which you do when reading it all at once

[maiden karma]

Just use system.arraycopy