Switch Statement in Java

Suppose you are building a small program that needs to perform different actions depending on a particular value.

For example, imagine you have a person's age and you want to show a specific message when their age is 18 or 60.

You could write this using an if-else ladder:

int age = 18;

if (age == 18) {
    System.out.println("Go and apply for driving license");
} else if (age == 60) {
    System.out.println("It's time to retire");
} else {
    System.out.println("I have nothing to say about you");
}

This works perfectly fine. But when we have multiple fixed values that we want to compare against the same variable, a switch statement can make the code easier to read.

The basic idea is simple:

Take one value and check which case matches that value.

Basic Switch Syntax

The traditional syntax of a switch statement looks like this:

switch (expression) {

    case value:
        // code
        break;

    case value:
        // code
        break;

    default:
        // code
        break;
}

Here, the expression is the value that Java will check.

For example:

int age = 18;

switch (age) {

    case 18:
        System.out.println("Go and apply for driving license");
        break;

    case 60:
        System.out.println("It's time to retire");
        break;

    default:
        System.out.println("I have nothing to say about you");
        break;
}

Here, age is passed to the switch.

Java then checks the cases one by one.

If age contains 18, this case matches:

case 18:

So Java executes:

System.out.println("Go and apply for driving license");

If age contains 60, then this case matches instead:

case 60:

and Java prints:

It's time to retire

What Is default?

You can think of default as the final option when none of the cases match.

For example, what happens if:

int age = 21;

There is no:

case 21:

So Java won't execute either case 18 or case 60.

Instead, it reaches:

default:
    System.out.println("I have nothing to say about you");

The output will be:

I have nothing to say about you

So, in a simple way:

• case handles a particular value.

• default handles the situation when no case matches.

Why Do We Need break?

This is one of the most important things to understand about the traditional switch statement.

Suppose we have:

int age = 60;

switch (age) {

    case 18:
        System.out.println("Go and apply for driving license");
        break;

    case 60:
        System.out.println("It's time to retire");

    case 45:
        System.out.println("You have covered your half life");
        break;

    default:
        System.out.println("I have nothing to say about you");
        break;
}

The value of age is 60.

So Java finds:

case 60:

and executes:

System.out.println("It's time to retire");

But without a break, Java can continue executing the statements in the following cases.

So you may also see:

It's time to retire
You have covered your half life

This behavior is called fall-through.

To stop execution after the matching case, we use:

break;

So we should write:

case 60:
    System.out.println("It's time to retire");
    break;

Now, as soon as Java executes break, it exits the switch statement.

Real-World Example

Imagine a manufacturing machine with different status codes.

You could have:

int status = 2;

switch (status) {

    case 1:
        System.out.println("Machine is starting");
        break;

    case 2:
        System.out.println("Machine is running");
        break;

    case 3:
        System.out.println("Machine needs maintenance");
        break;

    default:
        System.out.println("Unknown machine status");
        break;
}

If the status is 2, Java finds case 2 and prints:

Machine is running

The break then stops Java from moving into the next case.

This is the kind of situation where a switch statement becomes quite readable. You have one value, and that value can represent different fixed options.

Switch Statement vs Else-If Ladder

The same age example could be written using an else-if ladder:

if (age == 18) {
    System.out.println("Go and apply for driving license");
} else if (age == 60) {
    System.out.println("It's time to retire");
} else {
    System.out.println("I have nothing to say about you");
}

Or using a traditional switch:

switch (age) {

    case 18:
        System.out.println("Go and apply for driving license");
        break;

    case 60:
        System.out.println("It's time to retire");
        break;

    default:
        System.out.println("I have nothing to say about you");
        break;
}

Both can solve this type of problem.

When there are many fixed cases, a switch statement can make the structure easier to read compared with a large else-if ladder.

Key Takeaway

The traditional switch statement allows us to compare one expression against multiple cases.

The important parts are:

switch → value being checked
case → possible matching value
default → no case matched
break → exit the switch

This is the traditional or old-school switch syntax discussed in the video. Modern Java also provides another way of writing switch logic that doesn't require break, which we'll look at next.