I need help with a Project for class

[deep ravine]

thats another check you can do, yeah

if(obj == this) {
    return true;
}```

although you shouldnt return false if its not

not something to worry about rn. all you need to worry about is the serials

[left tartan]

the this thing

before i had SRN there

would saying obj == this.SRN

[deep ravine]

nope

[left tartan]

no, its wrong

or no it won't be wrong?

[deep ravine]

that would be comparing the appliance itself to a serial number

rather than comparing 2 serial numbers

[left tartan]

oh

yeah ur right

[deep ravine]

the problem is, you cant access SRN from obj

obj.SRN does not work

otherwise you could just do this.SRN == obj.SRN (but using equals instead of ==)

[left tartan]

maybe i don't need to access it

[deep ravine]

you do

you want to access the serial from the object being compared

[left tartan]

then i don't know

[deep ravine]

thats the only way you'll be able to compare the serials

you need to introduce a new variable

remember Appliance o?

[left tartan]

yea

ok

so are u saying find a way to store the other serial number in o

[deep ravine]

we need to somehow access the serial number from obj

but the variable obj is Object

the actual value is Appliance, the variable obj will reference an Appliance object

but obj... its an Object

so, introduce a new variable, and assign obj to it

Appliance app = obj;```

Java wont let you do that directly, you gotta "cast"

[left tartan]

casting is just the parenthesis right

[deep ravine]

(Appliance) obj```

yup

[left tartan]

yup u just right that

no eqaul to?

Appliance app = (Appliance) obj ?

[deep ravine]

all this does is give you access to SRN

obj always had SRN. but since the variable datatype was Object, it wasnt visible

so you created a new variable, with the proper datatype

now you can access SRN

you still gotta check if the serials are equal

but now you have access to SRN, with your new variable

btw, once you're finished, make sure you look over this code like 20 times, make sure you understand every last drop

because these struggles are only temporary, if you take that route

otherwise, these struggles can last years

[left tartan]

 @Override
    public boolean equals(Object obj){
        if(obj instanceof Appliance){
            return true;
        }
            else{  
                return false;
            }
    
Appliance app = (Appliance) obj;
if(obj.equals(app))
return true;
}

[deep ravine]

so you just threw the code at the bottom of the method

[left tartan]

oh right the brackets

[deep ravine]

you need to think of the if, the branching thats going on

you should only compare if its an appliance

and you shouldnt just return true, you should only return true if the SRNs are equal

[left tartan]

oh i think i wrote it wrong

at least this part i need to know

Appliance app = (Appliance) obj;

did i properly cast it

[deep ravine]

yup

[left tartan]

ok so after i did that

i can use app to check with obj right

[deep ravine]

wait

[left tartan]

yea

[deep ravine]

you should only do that if obj is actually an appliance

show your current code

[left tartan]

right

 @Override
    public boolean equals(Object obj){
        if(obj instanceof Appliance){
            return true;
        }
            else{  
                return false;
            }
    
Appliance app = (Appliance) obj;
if(obj.equals(app))
return true;
}```

[kind path]

Detected code, here are some useful tools:

[left tartan]

its currently that rn

[deep ravine]

step through it

[left tartan]

if it returns true

it'll end?

before it reaches the other code

[deep ravine]

nah, step by step man, break it down, line by line

lets pretend someone calls this method. they pass in a Dog

first thing that happens? java if(obj instanceof Appliance)

[left tartan]

ok if obj in part of appliance, return true

[deep ravine]

but its a Dog being passed in

[left tartan]

then false

[deep ravine]

its not gonns return true, itll go to the else

correct

[left tartan]

wait

[deep ravine]

now, pretend an Appliance is passed in

[left tartan]

obj u said

can be anything

if it can be anything

it'll always be true

[deep ravine]

hm?

[left tartan]

no hold on i migth've mixed it up

[deep ravine]

line by line, think of it, don't jump to conclusions

[left tartan]

u said this

[deep ravine]

yes

[left tartan]

no but tis checking

that line isn't the problem

[deep ravine]

obj = new Dog(), it references a dog. what happens in your code? line by line

i know its not

your understanding is the problem

thats why we are stepping through

first thing that happens, first line

[left tartan]

ok if it gets dog

it'll go to else

like u said

[deep ravine]

yup, easy, method ends

[left tartan]

and then it ends

[deep ravine]

now, obj = new Appliance()

first thing that happens?

it gets checked, still

if(obj instanceof Appliance)```

but now its actually true

so what happens next?

[left tartan]

the idea is to make it go onto the rest of the code

[humble oasis]

Please press ctrl+a and then ctrl+i in your java files. It will format them for you

[deep ravine]

yeah, but what does the code say? what actually happens?

[deep ravine]

now this is true. what happens next?

what does the code say?

[left tartan]

i think it goes into that block of code

[deep ravine]

it does. what does that block do?

[left tartan]

make a new appliance

[deep ravine]

does it?

[left tartan]

appliance app

[deep ravine]

whats in the block?

if(obj instanceof Appliance) {
    // it is an appliance
}```

what does your code do if its an appliance?

[left tartan]

return true

[deep ravine]

yup, method ends

so if its a dog or something, it goes to else, returns false, method ends

if its actually an appliance, it returns true, method ends

[left tartan]

the method shouldn't end

doesn't that mean i should reverse it

[deep ravine]

it shouldnt return true right away

you're right

all the code thats at the bottom

[left tartan]

like this

if (!(obj instanceof Appliance)) {
return false;

[deep ravine]

thats what you want to run

nope

[left tartan]

else true

oh

[deep ravine]

the code that you want to be ran

all that stuff you put at the bottom

[left tartan]

if out of scope

[deep ravine]

instead of just returning true, you want that code to run

[left tartan]

u were trying to say it would never go in because its outa scope?

[deep ravine]

so put that code in the block

yes

right now, the code you put at the bottom, its unreachable

because if its not an appliance, it returns false

if it is, it returns true

theres no way for the code at the bottom to be reached

[left tartan]

 @Override
    public boolean equals(Object obj){
        if(obj instanceof Appliance){
            return true;
        Appliance app = (Appliance) obj;
        if(obj.equals(app))
        return true;
        }
            else{  
                return false;
            }
}```

[deep ravine]

when do you want the code on the bottom to run?

[left tartan]

when its tru so

i need to move it up there

[deep ravine]

yes

exactly

you also need to fix your braces

if(...) {

} else {

}```

you have ```java
if(...) {

else {

}```

[left tartan]

 @Override
    public boolean equals(Object obj){
        if(obj instanceof Appliance){
            return true;
        Appliance app = (Appliance) obj;
        if(obj.equals(app)){
        return true;
        }
            else{  
                return false;
            }
}```

[deep ravine]

you are closer

read it line by line, again

pretend obj is an appliance

what happens?

start at the very first line

"it checks ..."

[left tartan]

ok so i'm trying to to compare obj that is an appliance to another one

[deep ravine]

"then ..."

[left tartan]

app

[left tartan]

if its an applalince

[deep ravine]

crystal

line by line

[left tartan]

and it is

[left tartan]

cause this

so it returns true

[deep ravine]

yes, so obj instanceof Appliance is true

yup

it returns true, exits the method

[left tartan]

does its in the block of the if statment

so it should

what

[deep ravine]

thats what you wrote

if(obj instanceof Appliance) 
    return true;```

the code is going to do what you tell it. and thats what you told it

see the problem?

[left tartan]

ur gonna have to slap me

cause it's not clicking 😭

why won't it go to next code

[deep ravine]

because you told it to return

[left tartan]

oh yeah

without doing anything

i told it to return

[deep ravine]

exactly

[left tartan]

 @Override
    public boolean equals(Object obj){
        if(obj instanceof Appliance){
  Appliance app = (Appliance) obj;
        if(obj.equals(app)){
            return true;
         }
            else{  
                return false;
            }
}```

ok so if its an appliance

it'll do Appliance app = (Appliance) obj;

this

then check with it

or so if(obj.equals(app)){

i should if i wrote that right

[humble oasis]

Once you know obj is of type appliance why do you make app and then compare it to obj

[left tartan]

to see if it equal each other

[deep ravine]

you are so much closer now

question is, do you understand what your code is doing?

line by line

[left tartan]

alright can explain this one to make sure

Appliance app = (Appliance) obj;

this is casting to applaince

casting the obj

but i guess its going in app

so i'm comparing the wrong thing

am i just comparing the same thing

[deep ravine]

Object obj and Appliance app are variables

[left tartan]

but hasn't obj been cast

to appliance

does that not mean it becomes a appliance too through app?

[deep ravine]

its already an appliance. you gotta think of "data/values" and "variables" separately

Object app = new Appliance();
Object dog = new Dog();
Object tv = new TV();```

[left tartan]

so what ur saying is i'm comparing a vairble to a datatype?

[humble oasis]

In java, every class/object is considered of the type Object

You can pass a Double, String or whatever object you want into your equal function

But they will still have the type they originally had

It doesn't change

obj will remain the type you passed in, so all the methods will be the same

[deep ravine]

im saying obj is already an appliance. we just need to view it differently. instead of viewing it as an Object, you needed to view it as an Appliance

[humble oasis]

Once you know it's of type appliance, you already know it will have the same fields and methods

[left tartan]

okay

[deep ravine]

Object obj = new Appliance();
// cannot access Appliance things 

Appliance app = obj;
// same data, but now seen as an Appliance```

[left tartan]

but that makes it sound like

obj a

would be same thing as appliance a

[humble oasis]

It can be

All Appliance are Object but not all Object are Appliance

[deep ravine]

yeah, it is

they reference the same data

[left tartan]

but i can't just right obj a can i?

[deep ravine]

not sure what you mean

[left tartan]

Object obj = new Appliance();```

this thing

is this how u would write it

if u wanna declare a "appliance" varible

[deep ravine]

its abstraction

[left tartan]

ok

if i write

obj x.equals(appliance y)

that wouldn't be right would it?

if they can declare the same variles

But I’m asking I can’t just write obj x right?

Or can I

I understand it’s na appliance now

It can declare a appliance variable, a serial number

But it that how u would write it?

[left tartan]

btw i just realized u were talking about how this wasn't an appliance but in the second line it's seen as it now

[left tartan]

thxs btw

I'll continue this later I've really gotta go now since i got school tmw

I'll be back

[left tartan]

before i go though i was gonna say

after obj can now act like a appliance, it can make varibles like one, but appliance cant do that with object cause its not vice versa and sp since obj can make appliance varibles, u can decalre obj (some varible) and appliance (some varible) and see if they equal each other, just i'm not sure abotu the right syntex

[kind path]

@left tartan

Your question has been closed due to inactivity.

If it was not resolved yet, feel free to just post a message below
to reopen it, or create a new thread.

Note that usually the reason for nobody calling back is that your
question may have been not well asked and hence no one felt confident
enough answering.

When you reopen the thread, try to use your time to improve the quality
of the question by elaborating, providing details, context, all relevant code
snippets, any errors you are getting, concrete examples and perhaps also some
screenshots. Share your attempt, explain the expected results and compare
them to the current results.

Also try to make the information easily accessible by sharing code
or assignment descriptions directly on Discord, not behind a link or
PDF-file; provide some guidance for long code snippets and ensure
the code is well formatted and has syntax highlighting. Kindly read through
https://stackoverflow.com/help/how-to-ask for more.

With enough info, someone knows the answer for sure 👍

[uncut marsh]

what have you done until now?

do you still need help

[left tartan]

Yes I saw that for the equals, we could just use the code the professor provided for that part

This is what I have so far

btw

i got the sort thing fixed

it was just a cause of a simple curly bracket

now all the letters can be in order, just that now null prints in between 💀 so that might be cause of the mutple arrays

[kind path]

I uploaded your attachments as Gist.

[left tartan]

and this my appliance class

public class Appliance {


    private String SRN;


    public Appliance (String SRN) {
        this.SRN = SRN;

    }

    @Override
    public String toString() {
        return SRN;
    }

    public int compareTo (Appliance x) {
        return this.SRN.compareTo(x.SRN);

    }
    @Override
    public boolean equals(Object other){
        return other != null && getClass() == other.getClass() && SRN.equals(((Appliance) other).SRN);

    }


        public char convert(){
            return SRN.charAt(0);
        }

        public String getSRN() {
            return SRN;
        }

        public void setSRN(String SRN) {
            this.SRN = SRN;
        }


    }```

so far this is what i have

But i'm in class rn so i can't work on it atm so i'll be back once i'm home

oh right for the equals

lemme show the slide

[left tartan]

btw I think I might change the 3 separte arrays for each

cause i could maybe just check the letter in just one array and make that go in one the 3 collums in the gui somehow

or at least i hope i can

thats where i'm at now, i'll be back later

[uncut marsh]

@left tartan Do you know what are you doing here?:

Appliance twoDArr[][] = getTableArray();
for (var i: twoDArr) {
    for (var j: i) {
        System.out.println(j);
    }
}```

This is where you get nulls right? It's easy to know

[deep ravine]

please use descriptive names, too. short-hand names caused some confusion with your last problem, confusing o and y

descriptive names will make it easier to help, and also show us that you actually understand your code

[uncut marsh]

And make you able to understand your code if you didn't touch it for weeks or months

because it provides better context

[left tartan]

It was there to check how the whole array looked ye, I was explaining what I got up to in a hurry so I didn’t notice

[uncut marsh]

That happens because the 3 arrays are of size (all the serials), but it only includes the serial of one type, each one

[left tartan]

Ye it has the space of all of it together in each

[uncut marsh]

anyways, I don't think it matters a lot, because the assignment says it's ok to have partially filled arrays

[left tartan]

Oh yea

But if I’m to use the 2d array now to print that onto the gui

Actually maybe not

Cause if it checks just the letter

It should put it in one of the three boxes on there

[uncut marsh]

I don't understand

[left tartan]

And null just well disappears

Cause the gui is suppose to have three Collums separating each with their letter

[uncut marsh]

yes

[left tartan]

And so if I make it check

I can just tell it which text panel to go to

Or that’s the plan

[uncut marsh]

The table does that for you, you just have to set the column name

[left tartan]

Oh alright

Yeah I’ll see

[uncut marsh]

let's go to the constructor

[left tartan]

I’ll be back in a few hours man I have calc rn 😭

[uncut marsh]

ok

[left tartan]

Ye I shall be back

[uncut marsh]

I might made the getTableArray wrong, as I made, per column and not per row

ping me when you're ready

[uncut marsh]

@left tartan are you free?

[left tartan]

i have a class online rn

it ends at 8:30

actually that doesn't help if i say that cause diff timezones

bascially ends in an hour and 10 minutes from now

[uncut marsh]

ok

[left tartan]

alright i'm back

rn what i have legt to do is print the appliances onto the gui i believe

@uncut marsh

as of rn now this is what i got

[uncut marsh]

I'm a bit busy rn

but basically

You create a JScrollPane

add the table in the scroll pane

then add the scroll pane in the frame

I'll explain that later

[left tartan]

is that in the table one

    static Appliance[][] getTableArray() {
        SelectionSort();
        Appliance[] refrigerators = new Appliance[arr.length];
        Appliance[] dishwashers = new Appliance[arr.length];
        Appliance[] microwaves = new Appliance[arr.length];

        int r = 0, d = 0, m = 0;
        for(int i = 0; i < arr.length;i++){
            if (arr[i].convert() == 'R') {
                refrigerators[r] = arr[i];
                r++;
            }
            if (arr[i].convert() == 'D') {
                dishwashers[d] = arr[i];
                d++;
            }
            if (arr[i].convert() == 'M') {
                microwaves[m] = arr[i];
                m++;
            }
        }
        return new Appliance[][]{refrigerators, dishwashers, microwaves};
    }```

    public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setVisible(true);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    }

    public static void fillGUI() {
        


    }```

or should i put that in the empty method

I'll go and work on it then and see what i can do

[uncut marsh]

the table one is wrong:

what it does is to send an array of three arrays, each one with one type.

But the table will read as, "Ok. Let's take each array and convert it to a row!"

that will make it as a single row of refrigerators, a single row of microwaves, etc.

we will change it to modify the 2 dimensional array directly instead of adding the three arrays

[left tartan]

oh alright

[uncut marsh]

Ok I'm free now

[uncut marsh]

can you use setLocationRelativeTo(null)?

it will show in the center

[left tartan]

my prof only used the setLocation

[uncut marsh]

ok

I recommend putting setVisible last

[left tartan]

alright

[uncut marsh]

we will make fillGUI

there are two ways

[left tartan]

yea

[uncut marsh]

1. we make the frame a private static variable like arr

2. we pass frame to fillGUI

both work

[left tartan]

second one

mostly cause i already put frame in the parameters so mgiht as well

public static void fillGUI(JFrame body) {
        

}```

alright so

[uncut marsh]

call fillGUI before setVisible()

in makeGUI

then let's create a JTable

oh before that

create an array of Strings

for the column names

[left tartan]

can't i just append to make the column?

[uncut marsh]

how?

[left tartan]

i'm not too familiar i was trying to tell from the slides

i'll send what he sent

[uncut marsh]

Oh we aren't using containers 💀

[left tartan]

oh its not append

grid layout

[uncut marsh]

we create a String[]

[uncut marsh]

and in the JTable constructor, we use the 2d array and the column names

💀

[left tartan]

alright thats all i've got 💀

[uncut marsh]

that's a bit more complicated

your professor never told about JTable?

[left tartan]

no

[uncut marsh]

💀

[left tartan]

heard it from u the first time

[uncut marsh]

well we have to do that way 😭

[left tartan]

welp

alrighty

ok so

[uncut marsh]

we will have the 2D array as it is now

it works for this way

[left tartan]

ye

[uncut marsh]

make the layout thing with 3 columns

empty

and show your progress

we will fill it after

[left tartan]

is it just add?

and it creates another panel?

[uncut marsh]

this

GridLayout(1, 3)

[left tartan]

oh right i gotta do 1,3

[uncut marsh]

for 3 columns

[left tartan]

okay

    public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);

    }

    public static void fillGUI(JFrame body) {
        body.setLayout(new GridLayout(1,3);)
        


    }```

[uncut marsh]

you named it body

[left tartan]

oh right

[uncut marsh]

I think that is last

before we have to create the content panes

first

[left tartan]

okay

wait no

not this one

[left tartan]

gotta follow this

[uncut marsh]

so 3 text areas

one content pane

[left tartan]

actually it might've been that

cause that adding text

    public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);

    }

    public static void fillGUI(JFrame body) {
    Container myContentPane = gui.getContentPane();
    TextArea refeg = new TextArea();
    TextArea dishWash = new TextArea();
    TextArea micro = new TextArea();
    myContentPane.add(Refeg, BorderLayout.EAST);
    myContentPane.add(dishWash, BorderLayout.WEST);
    myContentPane.add(micro, BorderLayout.CENTER);



        body.setLayout(new GridLayout(1,3);)
        


    }```

[uncut marsh]

yeah then myContentPane.add() thing

3 times

[left tartan]

i thought gridlayout was the other alternative

[deep ravine]

theres a few things here

[left tartan]

this east west stuff

[deep ravine]

first, i would never recommend relying on the existing content pane. that exists for formality reasons

introduce your own panel, then set that panel as the content pane

otherwise you can wind up with some funky results, such as when using BoxLayout

[left tartan]

would changing the borderlayout to gridlayout be fine

wait i put it on the bottom

[deep ravine]

if you need gridlayout instead of borderlayout, sure

just make sure you understand what they do

[left tartan]

they do the same thing right?

[deep ravine]

not even close lmao

they are completely different layouts

[left tartan]

but they both give u mutiple panels

[deep ravine]

yeah, so do 99% of layouts

so does FlowLayout

[left tartan]

oh there is more

its not just those two

[deep ravine]

so does GridBagLayout

[left tartan]

well of course

[deep ravine]

there are tons

[left tartan]

java got alot of stuff

[deep ravine]

https://docs.oracle.com/javase/tutorial/uiswing///layout/

[left tartan]

and so i think i'd better use gridlayout

seemed more simple maybe

[uncut marsh]

It says grid layout

[deep ravine]

tons of layouts

[uncut marsh]

in your assignment

[left tartan]

but i would only need to say it once right

[left tartan]

ah

[deep ravine]

if your assignment says GridLayout, use GridLayout

read your assignment 😂

[left tartan]

indeed it does 💀

i thoght he was saying that generally

[deep ravine]

if you cant handle requirements from a school assignment, you will fail with real-world assignments

[left tartan]

so i just misread it

[deep ravine]

time to put more priority on that

[left tartan]

yea

ok so with gridlayout

i just need to say it once so thats means i just write java body.setLayout(new GridLayout(1,3);)

instead of contentpane border

    public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);

    }

    public static void fillGUI(JFrame body) {
    Container myContentPane = gui.getContentPane();
    TextArea refeg = new TextArea();
    TextArea dishWash = new TextArea();
    TextArea micro = new TextArea();
    body.setLayout(new GridLayout(1,3);)
    myContentPane.add(refeg);
    myContentPane.add(dishWash);
    myContentPane.add(micro);    

    }```

ok so now i do the adding

[uncut marsh]

setLayout should be last

i think

I never used that

[left tartan]

the gridlayout?

maybe

i can't tell either

[uncut marsh]

nah lets continue

if something is wrong we will fix it

[left tartan]

czuse they have it like this

[left tartan]

right

    public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);

    }

    public static void fillGUI(JFrame body) {
    Container myContentPane = gui.getContentPane();
    TextArea refeg = new TextArea();
    TextArea dishWash = new TextArea();
    TextArea micro = new TextArea();
    body.setLayout(new GridLayout(1,3);)
    myContentPane.add(refeg);
    myContentPane.add(dishWash);
    myContentPane.add(micro);    
    for(int i =0;i < arr.length;i++){


    }```

ok so now since we have the different panels

[uncut marsh]

before adding

[left tartan]

yea

[uncut marsh]

we have to append

there are two ways

[left tartan]

ok what does append do

put words in a box?

[uncut marsh]

let say you have this text area:

you append "A": A

[left tartan]

oh yea so it puts words in the textarea right

[uncut marsh]

you append "B" : AB

yeah

[left tartan]

okie dokie

[uncut marsh]

there are two ways

1. we use the the if arr[i].convert() == 'R' logic there and delete the getTableArray
2. we use the getTableArray

[left tartan]

wait is that jtable thing

[uncut marsh]

since your professor don't want you to use the JTable we won't need the table array

[left tartan]

if he didn't ever mention in to us, i assume we can't use it

ah ye

so first option it is

[uncut marsh]

so make a for loop that iterates from 0 to arr.length

again

[left tartan]

    public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);

    }

    public static void fillGUI(JFrame body) {
    Container myContentPane = gui.getContentPane();
    TextArea refeg = new TextArea();
    TextArea dishWash = new TextArea();
    TextArea micro = new TextArea();
    body.setLayout(new GridLayout(1,3);)
    for(int i =0;i < arr.length;i++){

    if ( (arr[i].convert() == 'R')){

    }
    if ( (arr[i].convert() == 'D')){

    }
    if ((arr[i].convert() == 'M') ){

    }

    }
    myContentPane.add(refeg);
    myContentPane.add(dishWash);
    myContentPane.add(micro);    


    }```

[uncut marsh]

should be before the myContentPane.add()

[left tartan]

oh yeah

[uncut marsh]

there we use the logic that we applied in the getTableArray function

if (arr[i].convert() ==

etc

[left tartan]

static Appliance[][] getTableArray() {
        SelectionSort();
        Appliance[] refrigerators = new Appliance[arr.length];
        Appliance[] dishwashers = new Appliance[arr.length];
        Appliance[] microwaves = new Appliance[arr.length];

        int r = 0, d = 0, m = 0;
        for(int i = 0; i < arr.length;i++){
            if (arr[i].convert() == 'R') {
                refrigerators[r] = arr[i];
                r++;
            }
            if (arr[i].convert() == 'D') {
                dishwashers[d] = arr[i];
                d++;
            }
            if (arr[i].convert() == 'M') {
                microwaves[m] = arr[i];
                m++;
            }
        }
        return new Appliance[][]{refrigerators, dishwashers, microwaves};
    }```

so the if there

[uncut marsh]

yeah

[left tartan]

3 ifs then

[uncut marsh]

we will change the content of the ifs

[uncut marsh]

yes

empty ifs

nono

[left tartan]

empty

right

[uncut marsh]

if (arr[i].convert() == 'R') {}

if without the body, but with the statement

@left tartan

[left tartan]

    public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);

    }

    public static void fillGUI(JFrame body) {
    Container myContentPane = gui.getContentPane();
    TextArea refeg = new TextArea();
    TextArea dishWash = new TextArea();
    TextArea micro = new TextArea();
    body.setLayout(new GridLayout(1,3);)
    for(int i =0;i < arr.length;i++){

    if ((arr[i].convert() == 'R')){
    refeg.append();
    }
    if ((arr[i].convert() == 'D')){
    dishWash.append();
    }
    if ((arr[i].convert() == 'M') ){
    mircro.append();
    }

    }
    myContentPane.add(refeg);
    myContentPane.add(dishWash);
    myContentPane.add(micro);    


    }```

[uncut marsh]

good

depending if its R D or M

we will use .append

[left tartan]

it'll place it in a certain pane

[uncut marsh]

yes

[left tartan]

what is concat mean

[uncut marsh]

refer.concat(arr[i]+"\n")

it will add it to the textArea

wait

let me check the presentation

[left tartan]

u mean this part?

[uncut marsh]

oh yeah

.append

[kind path]

Looks like you attempted to use a command? Please note that we only use slash-commands on this server 🙂

Try starting your message with a forward-slash / and Discord should open a popup showing you all available commands.
A command might then look like /foo 👍

[left tartan]

or this was the other one

[uncut marsh]

I mean .append not .concat

[left tartan]

oh ye

[uncut marsh]

my bad

[left tartan]

alright so

in the ifs

once it does the condition

the textarea.append

textarea being the names

[uncut marsh]

the column yes

each textarea is a column

if its a 'R', we add it to the refeg column

you put .append()

but .append() what

[left tartan]

yeah append the serieal number

so i gotta put that in there

wait its text

[uncut marsh]

yes

[left tartan]

i gotta use the array somehow

[uncut marsh]

*use

"I gotta sue the array somehow" sounds funny

[left tartan]

lol

ok but in the table thingy we had it return a 2d array

hold on

our 3 separte arrasy we made

that still stays there or no?

[uncut marsh]

we can delete the table thingy

we won't use it

[left tartan]

everything?

static Appliance[][] getTableArray() {
        SelectionSort();
        Appliance[] refrigerators = new Appliance[arr.length];
        Appliance[] dishwashers = new Appliance[arr.length];
        Appliance[] microwaves = new Appliance[arr.length];

        int r = 0, d = 0, m = 0;
        for(int i = 0; i < arr.length;i++){
            if (arr[i].convert() == 'R') {
                refrigerators[r] = arr[i];
                r++;
            }
            if (arr[i].convert() == 'D') {
                dishwashers[d] = arr[i];
                d++;
            }
            if (arr[i].convert() == 'M') {
                microwaves[m] = arr[i];
                m++;
            }
        }
        return new Appliance[][]{refrigerators, dishwashers, microwaves};
    }```

[uncut marsh]

the function getTableArray yes

[left tartan]

alright

[uncut marsh]

so you have

if ((arr[i].convert() == 'R')){
    refeg.append();
}```

refeg.append()

[left tartan]

   public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);

    }

    public static void fillGUI(JFrame body) {
    Container myContentPane = gui.getContentPane();
    TextArea refeg = new TextArea();
    TextArea dishWash = new TextArea();
    TextArea micro = new TextArea();
    body.setLayout(new GridLayout(1,3);)
    for(int i =0;i < arr.length;i++){

    if ((arr[i].convert() == 'R')){
    refeg.append(arr[i].toString());
    }
    if ((arr[i].convert() == 'D')){
    dishWash.append(arr[i].toString());
    }
    if ((arr[i].convert() == 'M') ){
    mircro.append(arr[i].toString());
    }

    }
    myContentPane.add(refeg);
    myContentPane.add(dishWash);
    myContentPane.add(micro);    


    }```

[uncut marsh]

you need to append something

[left tartan]

yeah

right

the srn in the array

    public static void main (String[] args) {
        readfile();
        SelectionSort();

        for (int i =0; i < arr.length; i++) {
            Appliance a = arr[i];
            System.out.println(a);
        }    

        Appliance twoDArr[][] = getTableArray();
        for (var i: twoDArr) {
            for (var j: i) {
                System.out.println(j);
            }
        }

        makeGUI();


    }```

so the twoDArr

[uncut marsh]

remember we used arr[i].convert()

[left tartan]

oh

[uncut marsh]

it appends the array element

we already have toString so I think its fine

[left tartan]

    @Override
    public String toString() {
        return SRN;
    }

    public int compareTo (Appliance x) {
        return this.SRN.compareTo(x.SRN);

    }
    @Override
    public boolean equals(Object other){
        return other != null && getClass() == other.getClass() && SRN.equals(((Appliance) other).SRN);
    }


    public char convert(){
        return SRN.charAt(0);
    }```

[uncut marsh]

yeh

[left tartan]

oh so the convert

i need to ask because i wanna be sure

we gotta append the serieal number in the panel

[uncut marsh]

yes

[left tartan]

that serial number will go through convert and gime the first letter

and in the if statement we cheek what letter it is

but that whole serial number

how do we retrive it

[uncut marsh]

arr[i].toString()

[left tartan]

ohhh

ok that actaully makes sense

   public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gui.setVisible(true);

    }

    public static void fillGUI(JFrame body) {
    Container myContentPane = gui.getContentPane();
    TextArea refeg = new TextArea();
    TextArea dishWash = new TextArea();
    TextArea micro = new TextArea();
    body.setLayout(new GridLayout(1,3);)
    for(int i =0;i < arr.length;i++){

    if ((arr[i].convert() == 'R')){
    refeg.append(arr[i].toString());
    }
    if ((arr[i].convert() == 'D')){
    dishWash.append(arr[i].toString());
    }
    if ((arr[i].convert() == 'M') ){
    mircro.append(arr[i].toString());
    }

    }
    myContentPane.add(refeg);
    myContentPane.add(dishWash);
    myContentPane.add(micro);    


    }```

[uncut marsh]

let's check if its working

run the code

[left tartan]

its red

[uncut marsh]

what

[left tartan]

what did i write wrong

[uncut marsh]

import

also

[left tartan]

ok lemme check what to import

[uncut marsh]

it's body not gui

[left tartan]

wait

isn't this in Jframe?

[uncut marsh]

what

[uncut marsh]

what you mean

with this

[left tartan]

the stuff like container or text area

or grid layout

[uncut marsh]

they are part of swing

and they're added to a JFrame

[left tartan]

this thing right

[uncut marsh]

yes

[left tartan]

but i have it

[uncut marsh]

wait

they're actually part of awt

[left tartan]

maybe if i remove extends JFrame

oh

[uncut marsh]

import java.awt.GridLayout;
import java.awt.TextArea;```

[uncut marsh]

we don't need the extends JFrame

[uncut marsh]

the semicolon

you named JFrame body

and you're using gui

[left tartan]

alright all colorful

[uncut marsh]

try it

[left tartan]

only this shows up

i thought the words would show up

[uncut marsh]

let's see

[left tartan]

are we not up to it yet?

lemme send the hwole code

[uncut marsh]

It could be the content pane or the JFrame

that isnt saving

[left tartan]

damn

[uncut marsh]

I see what's the issue

the name

not body

change it to gui

and the issue magically disappears

[left tartan]

but

[uncut marsh]

change every body to gui

[left tartan]

ok

even in the parameters?

[uncut marsh]

yes

[left tartan]

ok

re

alrigth lets se

😭

u know what

does that mean anything

[uncut marsh]

strange

[left tartan]

it shwos up everytime

i run

[uncut marsh]

Eclipse being ass

continue

[left tartan]

oh alright 😭

still blank sadly

[uncut marsh]

can you restart eclipse

[left tartan]

alright

[uncut marsh]

to see if the problem fixes

[left tartan]

even though i know i saved it

incase

casue im stupid

[kind path]

I uploaded your attachments as Gist.

[left tartan]

public class Appliance {

    private String SRN;

    public Appliance (String SRN) {
        this.SRN = SRN;

    }

    @Override
    public String toString() {
        return SRN;
    }

    public int compareTo (Appliance x) {
        return this.SRN.compareTo(x.SRN);

    }
    @Override
    public boolean equals(Object other){
        return other != null && getClass() == other.getClass() && SRN.equals(((Appliance) other).SRN);
    }


    public char convert(){
        return SRN.charAt(0);
    }

    public String getSRN() {
        return SRN;
    }

    public void setSRN(String SRN) {
        this.SRN = SRN;
    }
}```

ok lemme restart

ok i ran it again

[uncut marsh]

wait

[left tartan]

after opening eclipse again

ye

[uncut marsh]

I now checked your code

you didn't call fillGUI

you have to call it before setVisible

@left tartan

does it work now

[left tartan]

oh

[uncut marsh]

not there

[left tartan]

in makegui

[uncut marsh]

yes

[uncut marsh]

you have to pass the JFrame 💀

[left tartan]

ok

the gui right

[uncut marsh]

yes

[left tartan]

woah

now to make it vertical

damn thats cool

[uncut marsh]

just add a new line character

in the append

you have

arr[i].toString()

to add it

use +

to add strings

[left tartan]

in each of the ifs?

[uncut marsh]

yes

-or-

well not really, yes in the ifs

[left tartan]

wait is it inside the toString(+)

not the plus sign but

[uncut marsh]

no

in the append

arr[i].toString() + '\n'

[left tartan]

    public static void fillGUI(JFrame gui) {
        Container myContentPane = gui.getContentPane();
        TextArea refeg = new TextArea();
        TextArea dishWash = new TextArea();
        TextArea micro = new TextArea();
        gui.setLayout(new GridLayout(1,3));
        for(int i =0;i < arr.length;i++){

            if ((arr[i].convert() == 'R')){
                refeg.append(arr[i].toString()+ "\n");
            }
            if ((arr[i].convert() == 'D')){
                dishWash.append(arr[i].toString() + "\n");
            }
            if ((arr[i].convert() == 'M') ){
                micro.append(arr[i].toString()+ "\n");
            }

        }
        myContentPane.add(refeg);
        myContentPane.add(dishWash);
        myContentPane.add(micro);
    }```

[kind path]

Detected code, here are some useful tools:

[left tartan]

like that?

[uncut marsh]

instead of spaces

its

\n

[left tartan]

oh right new line

we can type in it too

[uncut marsh]

another thing

[left tartan]

ye

[uncut marsh]

add a safety check in the convert() method

let's say

oh we got a line

the line being

""

let's try to access the first element

StringIndexOutOfBoundsException

[left tartan]

oh that sounds familar

[uncut marsh]

check if the SRN length is 0

[left tartan]

this thing right

[uncut marsh]

before trying to access charAt(0)

[uncut marsh]

so we are in the convert() method

[left tartan]

public char convert(){
if (SRN.length() == 0) return X;
        return SRN.charAt(0);
    }```

[uncut marsh]

check first if its length is 0

before returning

[left tartan]

with an if?

[uncut marsh]

if (SRN.length() == 0)

[left tartan]

like that

[uncut marsh]

yes

lets return a character that we will use as "lol not found"

it could be space

X

N

etc

[left tartan]

X then

[uncut marsh]

yeah return 'X'

[left tartan]

like literally?

public char convert(){
if ((SRN.isEmpty()) return X;
        return SRN.charAt(0);
    }```

[uncut marsh]

yes

that works

[left tartan]

interesting

[uncut marsh]

I think it's done

[left tartan]

ok if it equals 0, that means the string isn't a word?

could u explain this line again

[uncut marsh]

yeah

an empty String

we can also use

.isEmpty()

[left tartan]

ohh

we haven't learned that

so i guess i'll just type x

[uncut marsh]

literally does the same thing

[left tartan]

should i write it then

[left tartan]

oh its separte

[uncut marsh]

yeah you can change it

[left tartan]

does that still go in covnert

[uncut marsh]

you can use

if (SRN.isEmpty())

or the one before

choose the one you prefer

[left tartan]

the second

its more understandable for me

[uncut marsh]

well then use it

[left tartan]

does this go in its own method

public char convert(){
if ((SRN.isEmpty()) return X;
        return SRN.charAt(0);
    }```

or its ok like that

[uncut marsh]

its ok

isEmpty() is part of String

SRN is a String

[left tartan]

alright

won't just writing x

gimme a problem

[uncut marsh]

check the fillGUI function

it doesn't have a case for X

so it won't add it to any column

it will be in the array though

[left tartan]

yeah but

i meant cause it shows this

[uncut marsh]

remember the syntax

String str = "X";
char chr = 'X';```

you're returning a char, not a String

so it needs simple quotes

[left tartan]

alright

ok good

but now one more problem

i can edit this panel

i don't think i'm supose to be able to do that

what do i do about that

[uncut marsh]

The assignment doesn't explicitly say you can't edit it ¯_(ツ)_/¯

lol

[left tartan]

thats true lol

but i doubt he'd be okay with a file that isn't protected or something

i was trying to do

.setEditable(false);

[uncut marsh]

refeg.setEditable(false);

yes

with the three

[left tartan]

but its just red 💀

the three?

oh the panels

i put it there

public static void makeGUI() {
        JFrame gui = new JFrame();
        gui.setEditable(false);
        gui.setTitle("Appliances");
        gui.setSize(640, 480);
        gui.setLocation(100,100);
        gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        fillGUI(gui);
        gui.setVisible(true);

    }```

[uncut marsh]

in fillGUI

after the for loop

[left tartan]

there?

[uncut marsh]

do you know in what belongs setEditable?

[left tartan]

wdym

isn't that saying make the gui not editable?

the box that pops up

[uncut marsh]

gui is a JFrame 😭

its just the empty frame

[left tartan]

wait really

gui is empty?

[uncut marsh]

it doesn't belong there

[left tartan]

ohh

[uncut marsh]

gui has a container

[left tartan]

we tell gui what to have

in the other method

before that

its empty

[uncut marsh]

yes

but

setEditable

is not a JFrame method

[left tartan]

no wonder it wasn't in this presentation

[uncut marsh]

how did you found out about setEditable

[left tartan]

asked classmates jsut now

they said thats what they used

[uncut marsh]

yes but

set editable is a TextArea method

not JFrame

or Container

[left tartan]

oh

wait but how would that work

textarea

[uncut marsh]

refeg.setEditable(false);
dishWash.setEditable(false);
micro.setEditable(false);``` 😭

[left tartan]

ok right those applainces are ebing printed

is only makes sense to write don't edit after u put them in a panel

or while u put them there

[uncut marsh]

yes

[left tartan]

and because those were made from the datatype textarea

doign .not edit and stuff

since tis part of it

works

ok

ok i shouldn't write that when they are being declared right

while they are being added?

  public static void fillGUI(JFrame gui) {
        Container myContentPane = gui.getContentPane();
        TextArea refeg = new TextArea();
        TextArea dishWash = new TextArea();
        TextArea micro = new TextArea();
        gui.setLayout(new GridLayout(1,3));
        for(int i =0;i < arr.length;i++){

            if ((arr[i].convert() == 'R')){
                refeg.append(arr[i].toString()+ "\n");
            }
            if ((arr[i].convert() == 'D')){
                dishWash.append(arr[i].toString() + "\n");
            }
            if ((arr[i].convert() == 'M') ){
                micro.append(arr[i].toString()+ "\n");
            }

        }
        myContentPane.add(refeg.setEditable(false))
        myContentPane.add(dishWash.setEditable(false));
        myContentPane.add(micro.setEditable(false));
    }```

[uncut marsh]

why

@left tartan setEditable is a void method

you can't add nothing to the pane

they should be outside

[left tartan]

doesn't that mean

i just the names

and then put dont edit

after everything in that method

[uncut marsh]

refeg.setEditable(false);
dishWash.setEditable(false);
micro.setEditable(false);
myContentPane.add(refeg);
myContentPane.add(dishWash);
myContentPane.add(micro);```

[left tartan]

yeah its green

so it was that

and u say it before

[deep ravine]

these swing things can get confusing. Nemux seems to be on a good track

you guys lmk if you need extra input

[left tartan]

cause the thing prints after

yay it's edit proof

[uncut marsh]

now it's done right

[left tartan]

i beleive so

[uncut marsh]

A question

[left tartan]

no edit, all of them printed

and sorted

yea

[uncut marsh]

does your prof ask you how you do that x in class?

[left tartan]

no

wait what x

[uncut marsh]

anyways you have to understand

[left tartan]

u mean the one in the panel?

isn't that the close thigny

[uncut marsh]

x can be anything

[left tartan]

gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);```

[left tartan]

oh u meant the other one

public char convert(){
        if ((SRN.isEmpty())) return 'X';
        return SRN.charAt(0);
    }```

[uncut marsh]

anyways I meant

that you have to understand what you doing here so that you can apply your knowledge later

e.g if you have an exam

[left tartan]

yea

[uncut marsh]

ask me any questions about your code

[left tartan]

ok lemme put it all here again

[uncut marsh]

if you don't understand what its doing or how

[left tartan]

and look

[kind path]

I uploaded your attachments as Gist.

[left tartan]

public class Appliance {

    private String SRN;

    public Appliance (String SRN) {
        this.SRN = SRN;

    }

    @Override
    public String toString() {
        return SRN;
    }

    public int compareTo (Appliance x) {
        return this.SRN.compareTo(x.SRN);

    }
    @Override
    public boolean equals(Object other){
        return other != null && getClass() == other.getClass() && SRN.equals(((Appliance) other).SRN);
    }


    public char convert(){
        if ((SRN.isEmpty())) return 'X';
        return SRN.charAt(0);
    }

    public String getSRN() {
        return SRN;
    }

    public void setSRN(String SRN) {
        this.SRN = SRN;
    }
}```

[kind path]

Detected code, here are some useful tools:

[left tartan]

gimme a minu

i ma read it all

ok so

starting with the main

    public static void main (String[] args) {
        readfile();
        SelectionSort();

        for (int i =0; i < arr.length; i++) {
            Appliance a = arr[i];
            System.out.println(a);
        }    

        makeGUI();
    }```

its reading the file to get the serial numbers

putting them in array

[uncut marsh]

yes

[left tartan]

the selectionsort sorts in the array in chronological order

after thats done

[uncut marsh]

*Alphabetical

[left tartan]

right yeah

hmm

selectionsort only sorts them in that order

there is still checking the letter

and put them in each panel

so

actaully lemme check where

in fillgui

which is called in makegui

and thats called

in the main

after the for loop

[uncut marsh]

yes

[left tartan]

this may be a stupid question but

the print is before the makegui

[uncut marsh]

yes, it prints to the console

before creating the gui

[left tartan]

doesnt the forloop print

ohhh

[uncut marsh]

so you don't actually need it

[left tartan]

so thats why it still printed the numbers there

[uncut marsh]

in your assignment

it was just to check if the array was ordered

[left tartan]

oh alright

[uncut marsh]

before we created the gui

you can delete it if you want

[left tartan]

can i keep it there

yea

ok cool

i guess lets go over the count part again

public static void readfile (){
        String filename = "Project1.txt";
        TextFileInput in = new TextFileInput(filename);
        String line;
        int count = 0;
        while ((line = in.readLine()) != null){ 
            count++; 
        }
        in = new TextFileInput(filename);
        arr = new Appliance[count];
        while ((line = in.readLine()) != null){ 
            count --; 
            arr[count] = new Appliance(line);
        }

        in.close();
    }```

ok so

first we have something filename that has a link or holds the txt file

the TextFileInput helps looks into the whole file

its reading all of it

and now line

is gonna have a single line in the file

it reads line by line

and since its in the whileloop

it'll keep reading line by line until it reaches the end of the file

and once it does

a counter we made

will iterate to the number of lines we passed

or read

ok now

we use in again to read the whole thing?

[uncut marsh]

the first loop

[left tartan]

why are we reading the whole thing again?

[uncut marsh]

counts the amount of lines

[left tartan]

right

[uncut marsh]

by iterating it

then we create the array with the length of the lines we read before

[left tartan]

oh wait cause we reached the end right

we need to go back into the begining

[uncut marsh]

yes

thats why you create a new TextFileInput

to "reset" the counter it has

[left tartan]

right the arr = new Appliance[count]

[uncut marsh]

creates a new array with the size of the lines

initializes the static variable

so we can use it

but it starts as everythin null

so we have to fill it

in the next loop

[left tartan]

reset the counter?

wdym

[uncut marsh]

not our counter

[left tartan]

oh

the line counter

[uncut marsh]

the counter BufferedReader has

[uncut marsh]

yes