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

Claire Uzenski
Claire Uzenski
1,026 Points
Posted by Claire Uzenski
Claire Uzenski
1,026 Points

Having trouble with a similar question

I've started the shell for the @Before fixture for these tests. See how the Arrange part is duplicated in both tests, can you help me fix that please?

Use the @Before method to instantiate a new Calculator and use that instance in each method.

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

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

import static org.junit.Assert.*;

public class CalculatorTest {

    @Before
    public void setUp() throws Exception {

    }

    @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;
    }
}