# Lecture for February 8th

## Switch Statements

Another way to perform multiway branching. Comparing a variable and constant values (`String`, `int`, `char`)

Switch statements cannot be used with `boolean`, `double`, or `float`s

### Syntax

    switch (variable) {
      case value1:
        // Do something
        break;
      case value2:
        // Do something else
        break;
      //...
      default:
        // If all else fails do this
        break;
    }

`case` is a reserved word that means "when our variable in consideration is equal to..."

If you forget the `break` keyword, then the program will keep doing the work of all the statements until it hits a `break` keyword.

### Example Switch Syntax

    switch (birthday) {
      case 1:
        birthstone = "garnet";
        break;
      case 2:
        birthstone = "amethyst";
        break;
      // ....
      default:
        System.out.println("Not valid");
        break;
    }

## Comparing Strings Relationally

Comparing strings are based on the ASCII value of characters

Sorting strings will result in strings being in alphabetical or reverse alphabetical order. The values of the strings are compared character by character from the left with each ASCII value.

To compare strings use the `compareTo()` method. Here is the format of the call

    str1.compareTo(str2)

This returns a negative number when `str1` is less than `str2`

This returns `0` when `str1` is equal to `str1`

This returns a positive number when `str1` is greater than `str2`

### Example

    String a = "apple";
    String b = "banana";

    int x = a.compareTo(b); // x = -1

    int y = b.compareTo(a); // y = 1

## Ternary Operator

With a ternary operator, you can shorten statements where a value is determined by an if statement

    String output = "";
    if (movieRating > 4) {
      output = "Fan favorite";
    } else {
      output = "Alright";
    }

Is equivalent to

    String output = "";
    output = (movieRating > 4)? "Fan favorite": "Alright";

### Another Example

    double shipping;
    if (isPrimeMember) {
      shipping = 0;
    } else {
      shipping = 3.99;
    }

Is equivalent to

    double shipping = (isPrimeMember)? 0: 3.99;