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

using @Before to instantiate a object


This question seems to be pretty straight forward but I cant figure out what I am doing wrong.

Here is the 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.

Any help is much appreciated

package com.example;

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

import static org.junit.Assert.*;

public class CalculatorTest {

private Calculator calculator;

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

    public void addingMultipleNumbersProducesResult() throws Exception {
        int answer = calculator.addNumbers(1 ,2, 3);

        assertEquals(6, answer);

    public void addingSingleNumberTotalsAppropriately() throws Exception {
        int answer = calculator.addNumbers(1);

        assertEquals(1, answer);
package com.example;

public class Calculator {

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

1 Answer

I figured out my own question. @Before public void setUp() throws Exception { Calculator calculator = new Calculator(); }

I needed to remove the first Calculator