Java Boolean

In Java, the boolean data type represents one of two possible values: true or false. It is a fundamental data type used to represent binary values or logical states, and is often used in conditional expressions, loops, and to control program flow based on conditions.

Notes:

1. The boolean type does not have a specific size defined by the language. However, it is typically stored using one bit of memory.
2. The default value of a boolean is false.

Basic Declaration and Initialization

You can declare a boolean variable and assign it either true or false:

public class BooleanExample {
    public static void main(String[] args) {
        boolean isCMotherLanguage= true;  // Declare and initialize boolean variable
        boolean isJavaOnlyFrontendLanguage = false;

        System.out.println("Is C Mother Language of Programming? " + isCMotherLanguage);  // true
        System.out.println("Is Java Frontend Language? " + isJavaOnlyFrontendLanguage );  // false
    }
}

Boolean use in Conditional Statements

boolean values are often used in conditional statements to decide the flow of execution.

public class BooleanExample {
    public static void main(String[] args) {
        boolean isAdmin = true;

        if (isAdmin) {
            System.out.println("You are admin.");
        } else {
            System.out.println("You are not admin.");
        }
    }
}

Output:

Boolean use with Comparison Operators

You can use comparison operators (like ==, !=, <, >, etc.) to generate boolean values based on conditions.

public class BooleanComparisonExample {
    public static void main(String[] args) {
        int a = 20;
        int b = 10;
        
        boolean result1 = a > b;    // true because 20 is greater than 10
        boolean result2 = a == b;   // false because 20 is not equal to 10
        
        System.out.println("Is a greater than b= " + result1);  // true
        System.out.println("Is a equal to b= " + result2);      // false
    }
}

Output:

Boolean use with Logical Operators

Logical operators like && (AND), || (OR), and ! (NOT) can be used to combine or negate boolean expressions.

public class BooleanLogicalExample {
    public static void main(String[] args) {
        boolean isUser = true;
        boolean isAdmin = false;

        // Using AND (&&) operator
        boolean checkANDCondition= isUser && isAdmin;
        System.out.println("Check (AND): " + checkANDCondition);  // false

        // Using OR (||) operator
        boolean checkORCondition = isUser || isAdmin;
        System.out.println("Check (OR): " + checkORCondition);  // true

        // Using NOT (!) operator
        boolean isNotAdmin = !isAdmin;
        System.out.println("Check (Not): " + isNotAdmin);  // true
    }
}