Java Academy · Lesson

If Statements – Practice & Nested

Practice with nested if blocks, combine conditions safely, and compare strings correctly.

Lesson 2 of 38 steps

If Statements – Practice & Nested is a free Java Academy lesson on CoddyKit. This is lesson 2 of 3. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Java Academy learning path, and your progress syncs across the web and the CoddyKit app. The Java Academy course includes 3 lessons in total.

Lesson Goals

Goals: Practice if/else, write nested checks, and compare strings safely.

Nested if for multi-step decisions
Combine conditions with && and ||
Use equals for string comparison

Nested If

Nested if runs an inner check only when the outer condition is true.

public class Main {
    public static void main(String[] args) {
        int age = 16;

        if (age >= 0) {
            if (age < 18) {
                System.out.println("Minor");
            } else {
                System.out.println("Adult");
            }
        }
    }
}

Else-if vs Nested

else if chains mutually exclusive choices, while nested if is useful for multi-stage checks.

public class Main {
    public static void main(String[] args) {
        int score = 75;

        if (score >= 90) {
            System.out.println("A");
        } else if (score >= 80) {
            System.out.println("B");
        } else {
            System.out.println("Other");
        }
    }
}

String Equality

Compare strings with equals or equalsIgnoreCase.

name.equals("Ada")
"Ada".equals(name) avoids null pointer when name could be null
name.equalsIgnoreCase("ada") ignores case

Avoid == for strings; it compares references, not content.

Short-circuit

Short-circuit: && stops when the left side is false; || stops when the left side is true. Use this to guard checks:

public class Main {
    public static void main(String[] args) {
        String name = "Ada";

        if (name != null && name.equals("Ada")) {
            System.out.println("Welcome");
        }
    }
}

Nested If Demo

Try it: Enter a country code and age. See how nested checks choose the correct branch.

public class Main {
    public static void main(String[] args) {
        String country = "TR"; // manual input instead of Scanner
        int age = 20;          // manual input instead of Scanner

        if (!country.isEmpty()) {
            if (country.equalsIgnoreCase("TR")) {
                if (age >= 18) {
                    System.out.println("Adult in TR");
                } else {
                    System.out.println("Minor in TR");
                }
            } else {
                if (age >= 18) {
                    System.out.println("Adult outside TR");
                } else {
                    System.out.println("Minor outside TR");
                }
            }
        } else {
            System.out.println("No country provided");
        }
    }
}

String Compare Check

Quick check: Which are valid ways to check that name equals "Ada"?

Answer it in the interactive lesson

Recap & Next

Recap: You practiced nested if, contrasted else-if vs nesting, and used equals safely with short-circuit guards.

Next: Learn more operators and patterns for complex conditions.

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Frequently Asked Questions

Is the “If Statements – Practice & Nested” lesson free?

Yes — the full text of “If Statements – Practice & Nested” is free to read here on the web. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Java Academy course, upgrade to CoddyKit PRO. The Java Academy course includes 3 lessons in total.

What will I learn in “If Statements – Practice & Nested”?

Practice with nested if blocks, combine conditions safely, and compare strings correctly. You practise Java Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.

Do I need any experience to start Java Academy?

No prior experience is required. Java Academy on CoddyKit is structured for beginners through advanced learners, so you can start here or from the beginning and move at your own pace. This is lesson 2 of 3.

How long does the “If Statements – Practice & Nested” lesson take?

Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.

Can I write and run code in this Java Academy lesson?

Yes. Every Java Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.

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