Files, take out the products in alphabetical order and the most sold in capital letters

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Files, take out the products in alphabetical order and the most sold in capital letters

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#1 by (1 votes)

1

Good, I have the following problem: Given the following file: ventas.txt

platanos 5
fresas 8
fresas 3
arandanos 10
peras 2
platanos 1

Remove the products in alphabetical order, accumulated and the best sellers in capital letters. Example of execution:

arandanos 10
FRESAS 11
peras 2
platanos 6

I've tried this but it does not come anywhere near me.

public static void main(String[] args)
{
    File f = new File("/home/unknow/Documentos/ventas.txt");

    try
    {
        Scanner sc = new Scanner(f);

        int recolector;
        int mayor = Integer.MIN_VALUE;
        String palabra;
        String palabraMayor;
        while(sc.hasNext())
        {
            recolector = sc.nextInt();
            palabra = sc.nextLine();
            if(recolector > mayor)
            {
                mayor = recolector;
                palabraMayor = palabra.toUpperCase();
            }

        }
    }
    catch(IOException e)
    {
        System.out.println("Fichero no encontrado.");
    }


}

I do not know how to do it so that I select only the numbers of each line apart from the names.

java archivo

asked by AlejandroB 13.06.2018 в 21:20

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1 answer

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score 1 · Accepted Answer

I am going to help you with a part of your problem, which is not another one of separate what you receive per console in String and in an integer 'int' , and thus be able to work with those variables. I also help you when ordering alphabetically 'with an update that I've done' .

For this we are going to work with the split() method which divides a string of the matches of a regular expression passed as a parameter 'a blank space in this case'.

1) First I create an array of type Object[] to be able to store what comes to us through the console ..

Before entering the while () .. Object[] renglon;
And within the while .. renglon = sc.nextLine().split(" ");

2) Now we separate in 2 variables and store on the one hand the fruit of type String , and on the other hand the number of pieces in an integer int .

String fruta = (String) renglon[0];
int numero = Integer.parseInt((String)renglon[1]);

3) And now we print by console what each of these variables returns to us ..

System.out.println("Fruta: "+ fruta + " y he vendido "+numero+" piezas");

Result:

The complete example:

public static void main(String[] args) {
        File f = new File("C:\Development\ficheros\ventas.txt");

        try {
            Scanner sc = new Scanner(f);
            Object[] renglon;
            while (sc.hasNext()) {
                renglon = sc.nextLine().split(" ");
                String fruta = (String) renglon[0];
                int numero = Integer.parseInt((String) renglon[1]);

                System.out.println("Fruta: " + fruta + " y he vendido " + numero + " piezas");

            }
        } catch (IOException e) {
            System.out.println("Fichero no encontrado.");
        }
    }

Edit or Update ..

To make an order and compare values and others, I would create a POJO class apart ..

class MiFruta {
    String fruta;
    int pieza;

    public MiFruta(String fruta, int pieza){
        this.fruta = fruta;
        this.pieza = pieza;
    }

    public String getFruta() {
        return fruta;
    }

    public void setFruta(String fruta) {
        this.fruta = fruta;
    }

    public int getPieza() {
        return pieza;
    }

    public void setPieza(int pieza) {
        this.pieza = pieza;
    }

}

In the class where we extract from the file it would create a list to keep the fruits with the respective pieces.

List<MiFruta> lasFrutas = new ArrayList<>();

Inside the while we initialize each of the objects of the MyFruit class

MiFruta frutasVarias = new MiFruta(fruta, numero);

And we add them to our list

lasFrutas.add(frutasVarias);

And out of the while we could make the comparisons and print them in alphabetical order for example ..

System.out.println("----------Despues de ordenar nuestras frutas---------");
Collections.sort(lasFrutas, Comparator.comparing(MiFruta::getFruta));
for (MiFruta mf : lasFrutas){
    System.out.print("MiFruta "+ mf.getFruta());
    System.out.println("..Piezas "+ mf.getPieza());
}

And it would throw us as a result ..