Comparison & Logical Operators

Comparison operators compare two values and return true/false. Logical operators combine multiple conditions. Together, they form the foundation for decision-making in your programs. This is a foundational concept in enterprise application development that professional developers rely on daily. The explanations below are written to be beginner-friendly while covering the depth and nuance that comes from real-world Java experience. Take your time with each section and practice the examples

40 min•By Priygop Team•Last updated: Feb 2026

Comparison & Logical Operators

Example

public class ComparisonLogical {
    public static void main(String[] args) {
        int age = 20;
        double gpa = 3.8;
        
        // Comparison Operators (return boolean)
        System.out.println("=== Comparison ===");
        System.out.println("age == 20: " + (age == 20));   // Equal to
        System.out.println("age != 18: " + (age != 18));   // Not equal
        System.out.println("age > 18: " + (age > 18));     // Greater than
        System.out.println("age < 25: " + (age < 25));     // Less than
        System.out.println("age >= 20: " + (age >= 20));   // Greater or equal
        System.out.println("gpa <= 4.0: " + (gpa <= 4.0)); // Less or equal
        
        // Logical Operators (combine conditions)
        System.out.println("\n=== Logical ===");
        boolean isAdult = age >= 18;
        boolean hasGoodGrades = gpa >= 3.5;
        
        // AND (&&) — both must be true
        System.out.println("Adult AND good grades: " + (isAdult && hasGoodGrades));
        
        // OR (||) — at least one must be true
        System.out.println("Adult OR good grades: " + (isAdult || hasGoodGrades));
        
        // NOT (!) — reverses the boolean
        System.out.println("NOT adult: " + (!isAdult));
        
        // Practical example
        boolean eligible = (age >= 18) && (gpa >= 3.0);
        System.out.println("\nScholarship eligible: " + eligible);
    }
}

Try It Yourself: Eligibility Checker

Try It Yourself: Eligibility CheckerJava

Java Editor

✓ ValidTab = 2 spaces

public class EligibilityChecker {
    public static void main(String[] args) {
        // Change these values to test different scenarios!
        int age = 22;
        double gpa = 3.5;
        boolean hasID = true;
        int yearsExperience = 2;
        
        // Check various conditions
        boolean canVote = age >= 18;
        boolean canDrive = age >= 16 && hasID;
        boolean canApplyJob = age >= 21 && yearsExperience >= 1;
        boolean honorStudent = gpa >= 3.7;
        boolean deansList = gpa >= 3.5 && gpa < 3.7;
        
        System.out.println("=== Eligibility Results ===");
        System.out.println("Can Vote: " + canVote);
        System.out.println("Can Drive: " + canDrive);
        System.out.println("Can Apply for Job: " + canApplyJob);
        System.out.println("Honor Student: " + honorStudent);
        System.out.println("Dean's List: " + deansList);
    }
}

Output

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Edit the code on the left, then click Run

Java|23 lines|905 chars|✓ Valid syntax

UTF-8

Quick Quiz: Comparison & Logic

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Comparison & Logical Operators

40 min•By Priygop Team•Last updated: Feb 2026

Comparison & Logical Operators

Example

public class ComparisonLogical {
    public static void main(String[] args) {
        int age = 20;
        double gpa = 3.8;
        
        // Comparison Operators (return boolean)
        System.out.println("=== Comparison ===");
        System.out.println("age == 20: " + (age == 20));   // Equal to
        System.out.println("age != 18: " + (age != 18));   // Not equal
        System.out.println("age > 18: " + (age > 18));     // Greater than
        System.out.println("age < 25: " + (age < 25));     // Less than
        System.out.println("age >= 20: " + (age >= 20));   // Greater or equal
        System.out.println("gpa <= 4.0: " + (gpa <= 4.0)); // Less or equal
        
        // Logical Operators (combine conditions)
        System.out.println("\n=== Logical ===");
        boolean isAdult = age >= 18;
        boolean hasGoodGrades = gpa >= 3.5;
        
        // AND (&&) — both must be true
        System.out.println("Adult AND good grades: " + (isAdult && hasGoodGrades));
        
        // OR (||) — at least one must be true
        System.out.println("Adult OR good grades: " + (isAdult || hasGoodGrades));
        
        // NOT (!) — reverses the boolean
        System.out.println("NOT adult: " + (!isAdult));
        
        // Practical example
        boolean eligible = (age >= 18) && (gpa >= 3.0);
        System.out.println("\nScholarship eligible: " + eligible);
    }
}

Try It Yourself: Eligibility Checker

Try It Yourself: Eligibility CheckerJava

Java Editor

✓ ValidTab = 2 spaces

public class EligibilityChecker {
    public static void main(String[] args) {
        // Change these values to test different scenarios!
        int age = 22;
        double gpa = 3.5;
        boolean hasID = true;
        int yearsExperience = 2;
        
        // Check various conditions
        boolean canVote = age >= 18;
        boolean canDrive = age >= 16 && hasID;
        boolean canApplyJob = age >= 21 && yearsExperience >= 1;
        boolean honorStudent = gpa >= 3.7;
        boolean deansList = gpa >= 3.5 && gpa < 3.7;
        
        System.out.println("=== Eligibility Results ===");
        System.out.println("Can Vote: " + canVote);
        System.out.println("Can Drive: " + canDrive);
        System.out.println("Can Apply for Job: " + canApplyJob);
        System.out.println("Honor Student: " + honorStudent);
        System.out.println("Dean's List: " + deansList);
    }
}

Output

Click ▶ Run to see the result

Edit the code on the left, then click Run

Java|23 lines|905 chars|✓ Valid syntax

UTF-8

Comparison & Logical Operators