else if Chains

Handle multiple mutually exclusive conditions in sequence using else if to create a decision chain.

Overview

When you have more than two possible outcomes, chain else if blocks together. Java evaluates conditions from top to bottom and executes only the first block whose condition is true. Once a match is found, all remaining else if and else blocks are skipped. else if chains are ideal when conditions are mutually exclusive and ordered (like grade ranges, age categories, or score bands). The order matters - put the most specific or restrictive condition first.

Key Points

•else if chains are evaluated top-to-bottom; the first true condition wins
•At most ONE block in an if/else-if/else chain will execute
•A final else (no condition) acts as a default catch-all for all other cases
•Order matters: if conditions overlap, earlier conditions shadow later ones
•Very long else-if chains on a single value (like a day number) are better written as switch
•Each condition is only checked if all previous conditions were false

Examples

Grade classification with else if

public class Main {
    public static void main(String[] args) {
        int score = 78;

        if (score >= 90) {
            System.out.println("Grade: A");
        } else if (score >= 80) {
            System.out.println("Grade: B");
        } else if (score >= 70) {
            System.out.println("Grade: C");
        } else if (score >= 60) {
            System.out.println("Grade: D");
        } else {
            System.out.println("Grade: F");
        }
    }
}

Score 78 matches score >= 70 (Grade C). All conditions below that are skipped.

Ordering matters - specific conditions before general

public class Main {
    public static void main(String[] args) {
        int x = 15;

        // CORRECT: most specific first
        if (x > 20) {
            System.out.println("Greater than 20");
        } else if (x > 10) {
            System.out.println("Greater than 10"); // ← matches x=15
        } else {
            System.out.println("10 or less");
        }

        // WRONG ORDER: general condition catches everything
        if (x > 10) {                        // ← matches x=15 first
            System.out.println("Greater than 10");
        } else if (x > 20) {                 // ← never reached when x=15
            System.out.println("Greater than 20");
        }
    }
}

If you put the broad condition (x > 10) before the narrow one (x > 20), the narrow one can never be reached.

Season classifier

public class Main {
    public static void main(String[] args) {
        int month = 4; // April

        String season;
        if (month == 12 || month <= 2) {
            season = "Winter";
        } else if (month <= 5) {
            season = "Spring";
        } else if (month <= 8) {
            season = "Summer";
        } else {
            season = "Autumn";
        }

        System.out.println("Month " + month + ": " + season);
    }
}

else if is clean for range-based classification when values do not overlap.

Common Mistakes

Missing the else catch-all: if all conditions are false and there's no else, the variable may be uninitialised
Redundant conditions: `if (x >= 90) ... else if (x >= 80 && x < 90) ...` - the second condition can never reach x >= 90 since the first already checked that, so `x < 90` is redundant
Very deep else-if chains (10+) - switch statement is cleaner for exact-value matching

Note

If an else-if chain assigns a value to a variable, consider using a single-line ternary or a lookup structure (array/Map) for very simple cases. But for clarity, an else-if chain with 3–6 branches is perfectly readable.

else if Chains

Overview

Key Points

Examples

Common Mistakes

Note

Exercises

Knowledge Check

In an if/else-if/else chain, how many blocks can execute?