Interactive Coffee Vending Machine¶

Goal¶

In this lab, we'll take coffee orders from the keyboard in the terminal/console using the Java I/O classes and then display the order with its price.

JavaDoc Reference Links¶

Docs for Scanner: https://docs.oracle.com/javase/8/docs/api/index.html?java/util/Scanner.html

You can also look at the FAQ wiki for Scanner on Reddit: https://www.reddit.com/r/javahelp/wiki/scanner

Docs for String: https://docs.oracle.com/javase/8/docs/api/index.html?java/lang/String.html

Reference Example¶

Here's an example of using the Scanner class to get input from the terminal and display it:

  // create a new Scanner to read from the terminal console
  Scanner scanner = new Scanner(System.in);

  // display a prompt
  System.out.println("Name? ");

  // get some text
  String name = scanner.nextLine();
  System.out.println("Hi, " + name + ", nice to meet you.");

  // display an empty line
  System.out.println();

  // display the next prompt
  System.out.println("How many bagels?");

  // get the input as an int
  int qty = scanner.nextInt();
  System.out.println("OK, " + qty + " bagels coming up!");

Step 1: Create a Scanner Instance¶

In your application's main() method, create an instance of Scanner:

Scanner scanner = new Scanner(System.in);

Scanner's Package

The Scanner class is located in the java.util.Scanner package.

Step 2: Display a prompt and get the Coffee Size¶

Display a prompt (use System.out.println()) to ask for the coffee size by its first letter: S, M, or L.
Get a line of text from the user, using the nextLine() method that's on the scanner object.
```
String input = scanner.nextLine();
```
Take the string that's returned and convert it into the appropriate Size enum.
Use this Size to instantiate a CoffeeOrder and the display the full order.
Try it out before continuing.

Step 3: Creamer & Sweetener¶

Do the same thing as you did in Step 2 to ask for options for Creamer and Sweetener.

To make it easier on the user, only require the first letter or two for the choices.
- For the creamer, allow "m" for milk, "n" for none, and "h" for half-n-half.
- For the sweetener, allow "n" for none, "su" for sugar, and "sp" for Splenda.
Use the choices made to instantiate a CoffeeOrder and the display the full order using the display() method on the CoffeeOrder.
Try it out before continuing.

Step 4: Use While Loop¶

Surround your code with a while loop so you continue to ask for orders until the user exits.

while loops

Documentation for the while loop with break can be found here: https://books.trinket.io/thinkjava/chapter7.html#sec88

Questions:

How will you know when to exit the loop based on user input?
What code will you write to exit the loop?

Once you've completed the above steps, check in with the instructor to review your code.