Java switch Keyword

The Java switch keyword is used to execute one of many code statements. It can be considered as group of If-else statements.

Syntax

switch (expression){
  case 1:
     statement 1;
     break;
  case 2:
     statement 2;
     break;
     ...
     ...
     ...
  case N:
     statement N;
     break;
  default:
     default statement;
}

The Switch expression is evaluated and matched with the cases. When Case matches, the following block of code is executed.

Flow Diagram:

public class MyClass {
  public static void main(String[] args) {
    int i = 2;
    switch(i){
      case 1: 
         System.out.println("Red");
         break; 
      case 2: 
         System.out.println("Blue");
         break;
      case 3: 
         System.out.println("Green");
         break;
    }  
  }
}

The output of the above code will be:

Blue

Default case and break statement are optional here.

Default Case: Default Statement is executed when there is no match between switch expression and test cases.
Break Statement: Break statement is used to get out of the Switch statement after a match is found.

public class MyClass {
  public static void main(String[] args) {
    int i = 10;
    switch(i){
      case 1: 
         System.out.println("Red");
         break; 
      case 2: 
         System.out.println("Blue");
         break;
      case 3: 
         System.out.println("Green");
         break;
      default:
         System.out.println("There is no match in the switch statement.");
    }  
  }
}

The output of the above code will be:

There is no match in the switch statement.

❮ Java Keywords