Is there an easier/shorter code for switch case in this case?

Question

I have to sort a list of objects by the date provided in them. My initial thought was to use a switch case. But that means a maximum of 31 cases. Here is the code im using:

if (e.getSource() == btnSalesPerDay)
        {
            //int i =0;
            SalesTextArea.setText("");

            Object[] possibilities = {"1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13", "14", "15", "16", "17", "18", "19", "20", "21", "22", "23", "24", "25", "26", "27", "28", "29", "30", "31"};
            String dayOption = (String)JOptionPane.showInputDialog(frame,"Pick a day you wish to display the records for : ", "Catagory pick", JOptionPane.PLAIN_MESSAGE, null, possibilities,"ham");

            switch(dayOption)
            {
            case 1:
                if(salesdata[i].day == 1)
                {
                    int i =0;
                    while (salesdata != null)
                    {
                        SalesTextArea.insert("\t" + salesdata[i].totalPrice, 0);
                        SalesTextArea.insert("\t" + salesdata[i].year, 0);
                        SalesTextArea.insert("\t" + salesdata[i].month, 0);
                        SalesTextArea.insert("\t" + salesdata[i].day, 0);
                        SalesTextArea.insert("\t" + salesdata[i].customerName, 0);
                        SalesTextArea.insert("\t" + salesdata[i].salesNo, 0);
                        SalesTextArea.insert("\n", 0);
                        i++;
                    }
                }
                break;
case 2:
                if(salesdata[i].day == 2)
                {
                    int i =0;
                    while (salesdata != null)
                    {
                        SalesTextArea.insert("\t" + salesdata[i].totalPrice, 0);
                        SalesTextArea.insert("\t" + salesdata[i].year, 0);
                        SalesTextArea.insert("\t" + salesdata[i].month, 0);
                        SalesTextArea.insert("\t" + salesdata[i].day, 0);
                        SalesTextArea.insert("\t" + salesdata[i].customerName, 0);
                        SalesTextArea.insert("\t" + salesdata[i].salesNo, 0);
                        SalesTextArea.insert("\n", 0);
                        i++;
                    }
                }
                break;

It goes on up to the 31 cases.. My question is.. is there a simpler way? Whats the most efficient way to go about this?

Thanks :)

Answer 1

You just need a single loop:

String dayOption = (String)JOptionPane.showInputDialog(frame,"Pick a day you wish to display the records for : ", "Catagory pick", JOptionPane.PLAIN_MESSAGE, null, possibilities,"ham");

int chosenDay = Integer.parseInt(dayOption);
for (SalesData item : array) {
    if (item.day == chosenDay) {
        // ...
    }
}