Switch Statement in Java

25 Jun, 2022
The switch statement is a multi-way branch statement. In simple words, the Java switch statement executes one statement from multiple conditions. It is like an if-else-if ladder statement. It provides an easy way to dispatch execution to different parts of code based on the value of the expression. Basically, the expression can be a byte, short, char, and int primitive data types. It basically tests the equality of variables against multiple values.
Note: Java switch expression must be of byte, short, int, long(with its Wrapper type), enums and string. Beginning with JDK7, it also works with enumerated types (Enums in java), the String class, and Wrapper classes.
There can be any number of cases just imposing condition check but remember duplicate case/s values are not allowed.The value for a case must be of the same data type as the variable in the switch.The value for a case must be constant or literal. Variables are not allowed.The break statement is used inside the switch to terminate a statement sequence.The break statement is optional. If omitted, execution will continue on into the next case.The default statement is optional and can appear anywhere inside the switch block. In case, if it is not at the end, then a break statement must be kept after the default statement to omit the execution of the next case statement.
There can be any number of cases just imposing condition check but remember duplicate case/s values are not allowed.
The value for a case must be of the same data type as the variable in the switch.
The value for a case must be constant or literal. Variables are not allowed.
The break statement is used inside the switch to terminate a statement sequence.
The break statement is optional. If omitted, execution will continue on into the next case.
The default statement is optional and can appear anywhere inside the switch block. In case, if it is not at the end, then a break statement must be kept after the default statement to omit the execution of the next case statement.
Syntax: Switch-case 
// switch statement 
switch(expression)
{
   // case statements
   // values must be of same type of expression
   case value1 :
      // Statements
      break; // break is optional
   
   case value2 :
      // Statements
      break; // break is optional
   
   // We can have any number of case statements
   // below is default statement, used when none of the cases is true. 
   // No break is needed in the default case.
   default : 
      // Statements
}
Note: Java switch statement is a fall through statement that means it executes all statements if break keyword is not used, so it is highly essential to use break keyword inside each case.  
Chapters
descriptions off, selected
captions settings, opens captions settings dialog
captions off, selected
English
This is a modal window.
Beginning of dialog window. Escape will cancel and close the window.
End of dialog window.
Example: Consider the following java program, it declares an int named day whose value represents a day(1-7). The code displays the name of the day, based on the value of the day, using the switch statement.
Java
// Java program to Demonstrate Switch Case// with Primitive(int) Data Type  // Classpublic class GFG {      // Main driver method    public static void main(String[] args)    {        int day = 5;        String dayString;          // Switch statement with int data type        switch (day) {          // Case        case 1:            dayString = "Monday";            break;          // Case        case 2:            dayString = "Tuesday";            break;              // Case        case 3:            dayString = "Wednesday";            break;              // Case        case 4:            dayString = "Thursday";            break;          // Case        case 5:            dayString = "Friday";            break;              // Case        case 6:            dayString = "Saturday";            break;              // Case        case 7:            dayString = "Sunday";            break;          // Default case        default:            dayString = "Invalid day";        }        System.out.println(dayString);    }}
Friday
A break statement is optional. If we omit the break, execution will continue on into the next case. It is sometimes desirable to have multiple cases without break statements between them. For instance, let us consider the updated version of the above program, it also displays whether a day is a weekday or a weekend day.
Example:
Java
// Java Program to Demonstrate Switch Case// with Multiple Cases Without Break Statements  // Classpublic class GFG {      // main driver method    public static void main(String[] args)    {        int day = 2;        String dayType;        String dayString;          // Switch case        switch (day) {          // Case        case 1:            dayString = "Monday";            break;          // Case        case 2:            dayString = "Tuesday";            break;              // Case        case 3:            dayString = "Wednesday";            break;        case 4:            dayString = "Thursday";            break;        case 5:            dayString = "Friday";            break;        case 6:            dayString = "Saturday";            break;        case 7:            dayString = "Sunday";            break;        default:            dayString = "Invalid day";        }          switch (day) {            // Multiple cases without break statements          case 1:        case 2:        case 3:        case 4:        case 5:            dayType = "Weekday";            break;        case 6:        case 7:            dayType = "Weekend";            break;          default:            dayType = "Invalid daytype";        }          System.out.println(dayString + " is a " + dayType);    }}
Tuesday is a Weekday
We can use a switch as part of the statement sequence of an outer switch. This is called a nested switch. Since a switch statement defines its own block, no conflicts arise between the case constants in the inner switch and those in the outer switch.
Example:
Java
// Java Program to Demonstrate// Nested Switch Case Statement  // Classpublic class GFG {      // Main driver method    public static void main(String[] args)    {        // Custom input string        String Branch = "CSE";        int year = 2;          // Switch case        switch (year) {          // Case        case 1:            System.out.println(                "elective courses : Advance english, Algebra");              // Break statement to hault execution here            // itself if case is matched            break;              // Case        case 2:              // Switch inside a switch            // Nested Switch            switch (Branch) {              // Nested case            case "CSE":            case "CCE":                System.out.println(                    "elective courses : Machine Learning, Big Data");                break;              // Case            case "ECE":                System.out.println(                    "elective courses : Antenna Engineering");                break;                  // default case                // It will execute if above cases does not                // execute            default:                  // Print statement                System.out.println(                    "Elective courses : Optimization");            }        }    }}
elective courses : Machine Learning, Big Data
Example:
Java
// Java Program to Illustrate Use of Enum// in Switch Statement  // Classpublic class GFG {      // Enum    public enum Day { Sun, Mon, Tue, Wed, Thu, Fri, Sat }      // Main driver method    public static void main(String args[])    {          // Enum        Day[] DayNow = Day.values();          // Iterating using for each loop        for (Day Now : DayNow) {              // Switch case            switch (Now) {              // Case 1            case Sun:                System.out.println("Sunday");                  // break statement that hault further                // execution once case is satisfied                break;              // Case 2            case Mon:                System.out.println("Monday");                break;              // Case 3            case Tue:                System.out.println("Tuesday");                break;              // Case 4            case Wed:                System.out.println("Wednesday");                break;              // Case 5            case Thu:                System.out.println("Thursday");                break;              // Case 6            case Fri:                System.out.println("Friday");                break;              // Case 7            case Sat:                System.out.println("Saturday");                break;            }        }    }}
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
This article is contributed by Gaurav Miglani. If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to review-team@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.
harikesh409
Akanksha_Rai
vrk-19
sahilkansal09
nishkarshgandhi
solankimayank
java-basics
Java
School Programming
Java
Writing code in comment?
Please use ide.geeksforgeeks.org,
generate link and share the link here.
Split() String method in Java with examples
Arrays.sort() in Java with examples
Reverse a string in Java
Object Oriented Programming (OOPs) Concept in Java
How to iterate any Map in Java
Python Dictionary
Reverse a string in Java
Arrays in C/C++
Introduction To PYTHON
Inheritance in C++