Switch statement in Java - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a switch statement used for in Java?

A switch statement lets you choose between many options based on the value of a variable. It helps make decisions by matching the variable to different cases.

beginner

How do you write a basic switch statement in Java?

You write switch(variable) { case value1: //code break; case value2: //code break; default: //code }. The variable is checked against each case value, and the matching case runs.

intermediate

What happens if you forget to put break; in a switch case?

Without break;, Java continues running the next cases even if they don't match. This is called "fall-through" and can cause unexpected results.

intermediate

Can a switch statement handle strings in Java?

Yes! Since Java 7, switch statements can use strings as the variable to compare against case values.

beginner

What is the purpose of the default case in a switch statement?

The default case runs if none of the other cases match. It's like an 'else' to catch all other values.

What keyword stops execution from falling through to the next case in a switch statement?

A break

B continue

C stop

D exit

The break keyword stops the switch from running the next cases after a match.

Which of these types can be used in a switch statement in Java?

A int, String, enum

B double, float, long

C boolean, char, byte

D Object, Array, List

Switch supports int, String, and enum types, but not floating-point types or complex objects.

What happens if no case matches and there is no default case?

A It runs the first case anyway

B The program crashes

C It asks the user for input

D The switch does nothing and moves on

If no case matches and no default is provided, the switch block is skipped.

Which Java version introduced support for String in switch statements?

A Java 5

B Java 8

C Java 7

D Java 6

Java 7 added the ability to use Strings in switch statements.

What is the role of the case keyword in a switch statement?

A Ends the switch statement

B Defines a possible value to match

C Declares a variable

D Starts a loop

case defines a value that the switch variable is compared against.

Explain how a switch statement works and why you might use it instead of multiple if-else statements.

Think about choosing between many options based on one value.

Describe what happens if you omit the break statement in a switch case and give an example of when this might be useful.

Sometimes you want multiple cases to run the same code.