Java Conditional Statements

Java, like all other programming languages, is equipped with specific statements that allow us to check a condition and execute certain parts of code depending on whether the condition is true or false. Such statements are called conditional and are a form of a composite statement.

The Java if statement is used to test the condition. It checks the boolean condition: true or false. There are various types of if statements in Java.

• if statement
• if-else statement
• if-else-if ladder
• nested if statement

Java supports the usual logical conditions from mathematics:

• Less than: a < b
• Less than or equal to: a <= b
• Greater than: a > b
• Greater than or equal to: a >= b
• Equal to a == b
• Not Equal to: a != b

1. Java if Statement

The Java if statement tests the condition. It executes the if block if the condition is true.

Syntax:

1.   if(condition){  

2.   //code to be executed  

3.   }  

Example Code:

1.   //Java Program to demonstrate the use of if statement.  

2.   public class Example {  

3.   public static void main(String[] args) {  

4.       //defining an 'age' variable  

5.       int age=30;  

6.       //checking the age  

7.       if(age>19){  

8.           System.out.print("Age is greater than 19");  

9.       }  

10. }  

11. }  

2. Java if-else Statement

The Java if-else statement also tests the condition. It executes the if block if condition is true otherwise else block is executed.

Syntax:

1.   if(condition){  

2.   //code if condition is true  

3.   }else{  

4.   //code if condition is false  

5.   }  

Example Code:

1.   /A Java Program to demonstrate the use of if-else statement.  

2.   //It is a program of odd and even number.  

3.   public class IfElseExample {  

4.   public static void main(String[] args) {  

5.       //defining a variable  

6.       int number=13;  

7.       //Check if the number is divisible by 2 or not  

8.       if(number%2==0){  

9.           System.out.println("even number");  

10.     }else{  

11.         System.out.println("odd number");  

12.     }  

13. }  

14. }  

3. Java if-else-if ladder Statement

The if-else-if ladder statement executes one condition from multiple statements.

Syntax:

1.   if(condition1){  

2.   //code to be executed if condition1 is true  

3.   }else if(condition2){  

4.   //code to be executed if condition2 is true  

5.   }  

6.   else if(condition3){  

7.   //code to be executed if condition3 is true  

8.   }  

9.   ...  

10. else{  

11. //code to be executed if all the conditions are false  

12. }  

Example Code:

1.   //Java Program to demonstrate the use of If else-if ladder.  

2.   //It is a program of grading system for fail, D grade, C grade, B grade, A grade and A+.  

3.   public class IfElseIfExample {  

4.   public static void main(String[] args) {  

5.       int marks=65;  

6.         

7.       if(marks<50){  

8.           System.out.println("fail");  

9.       }  

10.     else if(marks>=50 && marks<60){  

11.         System.out.println("D grade");  

12.     }  

13.     else if(marks>=60 && marks<70){  

14.         System.out.println("C grade");  

15.     }  

16.     else if(marks>=70 && marks<80){  

17.         System.out.println("B grade");  

18.     }  

19.     else if(marks>=80 && marks<90){  

20.         System.out.println("A grade");  

21.     }else if(marks>=90 && marks<100){  

22.         System.out.println("A+ grade");  

23.     }else{  

24.         System.out.println("Invalid!");  

25.     }  

26. }  

27. }  

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Vaneesh Behl

Passionately writing and working in Tech Space for more than a decade.