Switch as else if in Java 20

In Java, the switch statement can be used as an alternative to multiple 'else if' statements. The syntax of the switch statement is as follows:

switch(expression) {
   case value1 :
      // code to be executed if expression is equal to value1
      break;
   case value2 :
      // code to be executed if expression is equal to value2
      break;
   case value3 :
      // code to be executed if expression is equal to value3
      break;
   .
   .
   .
   default :
      // code to be executed if expression doesn't match any case
}

Here's an example that uses switch statement to replicate else-if ladder:

int day = 3;
String dayString;
switch (day) {

    case 1:

        dayString = "Monday";

        break;

    case 2:

        dayString = "Tuesday";

        break;

    case 3:

        dayString = "Wednesday";

        break;

    case 4:

        dayString = "Thursday";

        break;

    case 5:

        dayString = "Friday";

        break;

    case 6:

        dayString = "Saturday";

        break;

    case 7:

        dayString = "Sunday";

        break;

    default:

        dayString = "Invalid day";

        break;

}
System.out.println(dayString);

In the above example, we have a variable day which is assigned a value of 3. The switch statement then evaluates the day variable and executes the corresponding code block based on its value. Since the value of day is 3, the code block for case 3 will be executed and the output will be "Wednesday".

Here's another example, this time using switch to check the grade of a student:

char grade = 'B';
String message;
switch (grade) {

    case 'A':

        message = "Excellent!";

        break;

    case 'B':

        message = "Good job!";

        break;

    case 'C':

        message = "You can do better";

        break;

    case 'D':

        message = "You need improvement";

        break;

    case 'F':

        message = "Fail";

        break;

    default:

        message = "Invalid grade";

        break;

}
System.out.println(message);

In the above example, we have a variable grade which is assigned a value of 'B'. The switch statement then evaluates the grade variable and executes the corresponding code block based on its value. Since the value of grade is 'B', the code block for case 'B' will be executed and the output will be "Good job!".