Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

Java Unit Testing in Java How to Test Using Before to not repeat yourself

Saud ALQahtani
Saud ALQahtani
7,842 Points

I've started the shell for the @Before fixture for these tests. See how the Arrange part is duplicated in both tests

I tried everything,,,,,,,,not working ....I NEED A CLEAR ANSWER

com/example/CalculatorTest.java
package com.example;

import org.junit.Before;
import org.junit.Test;

import static org.junit.Assert.*;

public class CalculatorTest {

    private Calculator calculator;

    @Before
    public void setUp() throws Exception {
        calculator = new Calculator();
    }

    @Test
    public void addingMultipleNumbersProducesResult() throws Exception {
        Calculator calculator = new Calculator();

        int answer = calculator.addNumbers(1 ,2, 3);

        assertEquals(6, answer);
    }

    @Test
    public void addingSingleNumberTotalsAppropriately() throws Exception {
        Calculator calculator = new Calculator();

        int answer = calculator.addNumbers(1);

        assertEquals(1, answer);
    }
}
com/example/Calculator.java
package com.example;

public class Calculator {

    public int addNumbers(int... numbers) {
        int total = 0;
        for (int number : numbers) {
            total += number;
        }
        return total;
    }
}

1 Answer

Anders Björkland
Anders Björkland
7,481 Points

Oh, don't give up, Saud!
You are so close. The thing with the @Before is that it is setting up the Calculator for you to use in the tests

...so that you don't have to set it up for each test. wink wink