junit 활용예시

junit 및 Mockito 활용예시를 정리해보았다.
자주 사용하는것들을 참고하기 위해..

import static org.assertj.core.api.Assertions.assertThat;
public class StringTest {
 @Test
 public void split() {
 	String[] values = "1".split(",");
 	assertThat(values).contains("1");
 	values = "1,2".split(",");
 	assertThat(values).containsExactly("1", "2");
 }
 @Test
 public void substring() {
 	String input = "(1,2)";
 	String result = input.substring(1, input.length() - 1);
 	assertThat(result).isEqualTo("1,2");
 }

 @Test
 public void arrayList() {
 	ArrayList<String> values = new ArrayList<>();
	 values.add("first");
	 values.add("second");
	 assertThat(values.add("third")).isTrue();
	 assertThat(values.size()).isEqualTo(3);
	 assertThat(values.get(0)).isEqualTo("first");
	 assertThat(values.contains("first")).isTrue();
	 assertThat(values.remove(0)).isEqualTo("first");
	 assertThat(values.size()).isEqualTo(2);
 }
}

import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;

public class CalculatorTest {
    Calculator cal;

    @BeforeEach
    public void setUp()  {
        cal = new Calculator();
    }

    @Test
    public void 덧셈()  {
        assertEquals(7, cal.add(3, 4));
    }

    @Test
    public void 뺄셈()  {
        assertEquals(1, cal.subtract(5,  4));
    }

    @Test
    public void 곱셉()  {
        assertEquals(6, cal.multiply(2, 3));
    }

    @Test
    public void 나눗셈()  {
        assertEquals(2, cal.divide(8, 4));
    }

    @AfterEach
    public void tearDown() {
        cal = null;
    }
}

import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;

import static org.assertj.core.api.Assertions.*;


public class StringTest {
    @Test
    void replace() {
        String actual = "abc".replace("b", "d");
        assertThat(actual).isEqualTo("adc");
    }

    @Test
    void containsTest() {

        String data = "1,2";
        String[] spitedData = data.split(",");

        assertThat(spitedData).contains("1");
    }

    @Test
    void equalTest() {
        String data = "1";
        String[] spitedData = data.split(",");
        assertThat(spitedData).containsExactly("1");
    }

    @DisplayName("Exception Test")
    @Test
    void charAtTest() {
        String arg = "abcd";
//        assertThatExceptionOfType(StringIndexOutOfBoundsException.class).isThrownBy(()->{
//            arg.charAt(5);
//        });

        assertThatThrownBy(()-> {
            arg.charAt(5);
        }).isInstanceOf(StringIndexOutOfBoundsException.class);
    }
}

import static org.assertj.core.api.Assertions.*;
import static org.junit.jupiter.api.Assertions.assertTrue;

import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.CsvSource;
import org.junit.jupiter.params.provider.ValueSource;

import java.util.HashSet;
import java.util.Set;

public class SetTest {
    private Set<Integer> numbers;

    @BeforeEach
    void setUp() {
        numbers = new HashSet<>();
        numbers.add(1);
        numbers.add(1);
        numbers.add(2);
        numbers.add(3);
    }


    @Test
    void sizeTest() {
        assertThat(numbers.size()).isEqualTo(3);
    }

    @ParameterizedTest
    @ValueSource(ints = {1, 2, 3})
    void contains(int num) {
        assertTrue(numbers.contains(num));
    }

    @ParameterizedTest
    @CsvSource(value = {"1:true", "2:true","4:false"}, delimiter = ':')
    void containsTest2(int num, boolean res) {
        assertThat(numbers.contains(num)).isEqualTo(res);
    }

}