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Anyone have knowledge about Java?
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Anyone have knowledge about Java?Posted:

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Trying to figure out how I can create a method that will allow the user to input the details of an object using the the scanner and add it to an ArrayList.

Basically doing a project where two products are stored and there's a customer menu and a staff menu and the staff menu needs to be able to add new stock items and adjust stock levels
#2. Posted:
5FDP_Jekyll
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There are numerous different ways it can be achieved, however, unless we know the variable types you're using not much can really be done. Posting those might help a little. Actually posting your source would be the most beneficial way that I could you.
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Guess this is kinda bad with me being at the end of my first year of information systems
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From what I can gather from that, you're not really giving any information to the scanner to tell it to change the stock amount. Also, with that route, in order to update the stock, you would have to delete and re-add the stock every time you change a value. This is because in order for their not to be a type mismatch, the entire list gets turned into a String, I believe anyways. So instead of the list being read as a "String, Double, Int, String", instead it gets read as a simple String. To be honest, I myself would go with variables rather than ArrayLists just because they'd be a bit easier to use.

Now I could be wrong myself in my explanation, after all, I myself am not too experienced in Java.
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5FDP_Jekyll wrote From what I can gather from that, you're not really giving any information to the scanner to tell it to change the stock amount. Also, with that route, in order to update the stock, you would have to delete and re-add the stock every time you change a value. This is because in order for their not to be a type mismatch, the entire list gets turned into a String, I believe anyways. So instead of the list being read as a "String, Double, Int, String", instead it gets read as a simple String. To be honest, I myself would go with variables rather than ArrayLists just because they'd be a bit easier to use.

Now I could be wrong myself in my explanation, after all, I myself am not too experienced in Java.

Thanks for the input unfortunately ArrayLists are required as part of the assignment spec
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-Raw wrote
5FDP_Jekyll wrote From what I can gather from that, you're not really giving any information to the scanner to tell it to change the stock amount. Also, with that route, in order to update the stock, you would have to delete and re-add the stock every time you change a value. This is because in order for their not to be a type mismatch, the entire list gets turned into a String, I believe anyways. So instead of the list being read as a "String, Double, Int, String", instead it gets read as a simple String. To be honest, I myself would go with variables rather than ArrayLists just because they'd be a bit easier to use.

Now I could be wrong myself in my explanation, after all, I myself am not too experienced in Java.

Thanks for the input unfortunately ArrayLists are required as part of the assignment spec
I had a feeling that was the case, if you search up ArrayList and how to use them, there's probably tons of topics on StackOverflow that you might find helpful, it's generally where I find my answers to my Java questions.
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Adding to an ArrayList is simple, you need to just use the .add() method.
Obviously depending on what you need to add to the ArrayList, you can get multiple inputs and capture each of them as part of your object to add to the ArrayList.


Scanner scanner = new Scanner(System.in);
ArrayList myArrayList = new ArrayList<>();

public static void main(String[] args) {
   String userInput = scanner.nextLine();
   int userInput2 = scanner.nextInt();
   MyClass myClass = new MyClass(userInput, userInput2);
   myArrayList.add(myClass);
}

public class MyClass {
   private String myString;
   private int myInt;
   
   public MyClass(String sIn, int iIn) {
      myString = sIn;
      myInt = iIn;
   }
   
   public void setString(String sIn) { myString = sIn; }
   public void setInt(int iIn) { myInt = iIn; }
   public String getString() { return myString; }
   public int getInt() { return myInt; }
}
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 public void addStockB()
    {
        //local variables
        String brand, type;
        double price;
        int stock;

        Scanner scan = new Scanner(System.in);
        Bass aBass;

        for (int i = 0; i < numberInstruments; i++)
        {
            //1. Input details from user
            System.out.println("\n Input Details Instrument " + (i + 1));
            System.out.print("Enter brand name : ");
            brand = scan.nextLine();
            System.out.print("Enter price : ");
            price = scan.nextDouble();
            System.out.print("Enter Stock level : ");
            stock = scan.nextInt();
            scan.nextLine();
            aBass = new Bass(brand, price, stock);           
            list.add(aBass);         
            {
                String fileName;
                ObjectOutputStream fileOut;
                try{
                    fileOut = new ObjectOutputStream(new FileOutputStream("shop.dat"));
                    for (Instruments inst : list)
                    {
                        fileOut.writeObject(inst);
                    }
                    fileOut.close();
                    System.out.println("Stock content saved");
                }
                catch (IOException e)
                {
                    System.out.println("error");
                }
            }
        }
    }


Thanks

Yeah I spent some time on it this morning and came out with this thought it worked but can't get the items to display when I run it
#9. Posted:
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Try making your own print() method in your Bass class.

Something like this:

public String toString() {
    String msg = brand; // String = brand name
    msg += " " + String.ValueOf(this.price); // msg = "Brand Price"
    msg += " " + String.ValueOf(this.stock); // msg = "Brand Price Stock"
    return msg;
}

main method {
    System.out.println(inst.toString());
}
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Cheers thanks for all the help
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