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Quick win: is it positive?

Write Apex · Beginner · 5 min · Runs in your Salesforce Developer org · Free

Scenario. A form shows a green tick when a quantity is above zero. You write the check.

Return true or false from a comparison. Meet the Boolean type and see what happens with null.

What you will learn

A comparison like age >= 18 is already a Boolean: it is true or false. You can return it straight away, no if needed.

Boolean isAdult(Integer age) {
    return age >= 18;
}

Gotcha. When the input is null, a comparison such as null > 0 is false. Apex does not throw here.

The task

Write a method isPositive(Integer n) that returns true for numbers above zero and false for everything else.

Examples:

• isPositive(5) → true
• isPositive(0) → false
• isPositive(null) → false

Requirements:

1. Return the result of comparing n with 0.
2. Zero is not positive.
3. Keep the method's name and its Integer input.

Starter code

Boolean isPositive(Integer n) {
    return null;
}

System.debug('5: ' + isPositive(5));
System.debug('0: ' + isPositive(0));

When it passes

`isPositive` returns true above zero, and false for zero, negative numbers and null.

Try this drill free

You write the Apex yourself. ApexSensei runs it and tells you what passed and what did not.

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