Switch Case

Syntax : Switch Case in Java Programming

1. It is alternative to else-if ladder.
2. Switch Case Syntax is similar to – C/C++  Switch.
3. Switch allows you to choose a block of statements to run from a selection of code, based on the return value of an expression.
4. The expression used in the switch statement must return an int, a String, or an enumerated value.

switch (selection) {  // value
case value1 :         // checking value 1
     statement(s);
     break;           // use to break switch flow if condition match
case value2 :         // checking value 2
     statement(s);
     break;
 .
 .
case value_n :
     statement(s);
     break;
default:
     statement(s);
}

Different Ways of Using Switch Case :

Switch Case Using Integer Case

int i=3; 

switch (i) {
case 1 :
     System.out.println("One player is playing this game.");
     break;
case 2 :
     System.out.println("Two players are playing this game.");
     break;
case 3 :
     System.out.println("Three players are playing this game.");
     break;
default:
     System.out.println("You did not enter a valid value.");
}

OutPut :

Three players are playing this game.

Switch Using String

String name = "Zubair";

switch (name) {

case "ALI" :
     System.out.println("ALI is playing this game.");
     break;

case "Zubair" :
     System.out.println("Zubair is playing this game.");
     break;

case "Ubaid" :
     System.out.println("Ubaid is playing this game.");
     break;

default:
     System.out.println("You did not enter a valid name.");
}

OutPut :

Zubair is playing this game.

• If you are coming from C/C++ then you must understand this concept that – Java Supports String Inside Case Label.
• Above program if used in C/C++ then it will give us compile time error.

How Switch Case Statement is different in java from c programming

1. In C Programming we were unable to write Case label of data type  ‘String’. In java we can have String inside “Switch”.

Example  : Choose Day of the Week

class SwitchDate{
  public static void main(String[] args){
  int week = 3;
  switch (week){
      case 1:
            System.out.println("monday");
            break;
      case 2:
            System.out.println("tuesday");
            break;
      case 3:
            System.out.println("wednesday");
            break;
      case 4:
            System.out.println("thursday");
            break;
      case 5:
            System.out.println("friday");
            break;
      case 6:
            System.out.println("saturday");
            break;
      case 7:
            System.out.println("sunday");
            break;
      default:
            System.out.println("Invalid week");
            break;
      }
  }
}

Output :

wednesday