switch statement in java
A switch statement allows a variable to be tested for equality against a list of values. Each value is called a case, and the variable being switched on is checked for each case.
Syntax
The syntax of enhanced for loop is −
switch(expression) { case value : // Statements break; // optional case value : // Statements break; // optional // You can have any number of case statements. default : // Optional // Statements }
The following rules apply to a switch statement −
The variable used in a switch statement can only be integers, convertable integers (byte, short, char), strings and enums.
You can have any number of case statements within a switch. Each case is followed by the value to be compared to and a colon.
The value for a case must be the same data type as the variable in the switch and it must be a constant or a literal.
When the variable being switched on is equal to a case, the statements following that case will execute until a break statement is reached.
When a break statement is reached, the switch terminates, and the flow of control jumps to the next line following the switch statement.
Not every case needs to contain a break. If no break appears, the flow of control will fall through to subsequent cases until a break is reached.
A switch statement can have an optional default case, which must appear at the end of the switch. The default case can be used for performing a task when none of the cases is true. No break is needed in the default case.
Flow Diagram
Example
Live Demopublic class Test { public static void main(String args[]) { // char grade = args[0].charAt(0); char grade = 'C'; switch(grade) { case 'A' : System.out.println("Excellent!"); break; case 'B' : case 'C' : System.out.println("Well done"); break; case 'D' : System.out.println("You passed"); case 'F' : System.out.println("Better try again"); break; default : System.out.println("Invalid grade"); } System.out.println("Your grade is " + grade); } }
Compile and run the above program using various command line arguments. This will produce the following result −
Output
Well done Your grade is C