Java “Loop” Program?

Tag: java,terminal,command-prompt

It's been a while since I've done some Java coding but here is a simple program, I did to calculate markup for my retail store. How would I be able to make the program loop until I close it myself? Right now, I run this program in my terminal/command prompt and each time I enter a value it ends, so I am forced to execute it again which takes some time (about .05 seconds or less) however I need all the time I can get with this task I am doing. So the point is to keep it running until I close it myself.

import static java.lang.System.out;
import java.util.Scanner;

public class ProductMarkup {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner myScanner = new Scanner(System.in);

        out.print("What is the quantity?");
        int quantity = myScanner.nextInt();
        out.print("What is the wholesale price?");
        double wsprice = myScanner.nextDouble();


        if (quantity == 1) {
            double math = (int) (wsprice * .70);
            double retail = math + wsprice;
            out.println(retail + 5);
        } else if (quantity == 2) {
            double math = wsprice * 2;
            double retail = math + 10;
            out.println(retail);
        } else if (quantity == 3) {
            double math = wsprice * 2.5;
            double retail = math + 5.75;
            out.println(retail);
        } else if (quantity == 4) {
            double math = wsprice * 2.80;
            double retail = math + 3.75;
            out.println(retail);
        }
    }

}

Best How To :

In Java, You can use one of the following three loops:

while Loop

A while loop is a control structure that allows you to repeat a task a certain number of times.

Syntax: The syntax of a while loop is:

while(Boolean_expression)
{
   //Statements
}

When executing, if the boolean_expression result is true, then the actions inside the loop will be executed. This will continue as long as the expression result is true.

do...while Loop

Syntax: The syntax of a do...while loop is:

do
{
   //Statements
}while(Boolean_expression);

Notice that the Boolean expression appears at the end of the loop, so the statements in the loop execute once before the Boolean is tested.

If the Boolean expression is true, the flow of control jumps back up to do, and the statements in the loop execute again. This process repeats until the Boolean expression is false.

for Loop

A for loop is a repetition control structure that allows you to efficiently write a loop that needs to execute a specific number of times.

A for loop is useful when you know how many times a task is to be repeated.

Syntax: The syntax of a for loop is:

for(initialization; Boolean_expression; update)
{
   //Statements
}

In the for loop case, you can use as follows if you want to repeat your processes for ever.

for(;;){
   whatever process you have
}

Hope from what I provide you can solve your problem.

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