JUnit 과 AssertJ 에 대한 소개

7. <dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
Maven

8. @Slf4j
public class Calculator {
/**
* 더하기
*
* @param nums 더하기 할 숫자들
* @return 합
*/
public double add(double... nums) {
log.trace("더하기... nums={}", nums);
double sum = 0.0;
for (double n : nums) {
sum += n;
}
log.debug("합={}", sum);
return sum;
}
}
@Slf4j
public class CalculatorTest {
@Test
public void testAdd() {
Calculator calculator = new Calculator();
Assertions.assertThat(calculator.add(1, 2)).isEqualTo(3);
}
}
@Slf4j
public class CalculatorTest {
@Test
public void testAdd() {
Calculator calculator = new Calculator();
assertThat(calculator.add(1, 2)).isEqualTo(3);
assertThat(calculator.add(-1, -2)).isEqualTo(-3);
assertThat(calculator.add()).isEqualTo(0);
}
}

11. Test Class
@Test
@Test
@Test
@Before
@BeforeClass
@AfterClass
@After
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12. @Test(expected = AssertionError.class, timeout = 1000L)
public void testAddException() {
Calculator calculator = new Calculator();
assertThat(calculator.add(1, 2)).isEqualTo(5);
}

13. @Slf4j
public class JUnitAnnotationTest {
private static Calculator calc;
@BeforeClass
public static void setupClass() throws Exception {
log.debug("Before Class...");
calc = new Calculator();
Thread.sleep(100L);
}
@Before
public void setup() {
log.debug("Before ...");
}
@After
public void cleanup() {
log.debug("@After...");
}
@AfterClass
public static void cleanupClass() {
log.debug("After Class...");
}
@Test
public void test1() {
log.debug("test1");
assertThat(calc).isNotNull();
}
@Test
public void test2() {
log.debug("test2");
assertThat(calc).isNotNull();
}
}
2016-01-15 11:40:55,935 DEBUG k.k.java.study.JUnitAnnotationTest.setup : Before ...
2016-01-15 11:40:55,935 DEBUG k.k.java.study.JUnitAnnotationTest.test1 : test1
2016-01-15 11:40:55,960 DEBUG k.k.java.study.JUnitAnnotationTest.cleanup : @After...
2016-01-15 11:40:55,961 DEBUG k.k.java.study.JUnitAnnotationTest.setup : Before ...
2016-01-15 11:40:55,962 DEBUG k.k.java.study.JUnitAnnotationTest.test2 : test2
2016-01-15 11:40:55,962 DEBUG k.k.java.study.JUnitAnnotationTest.cleanup : @After...
Before Class...2016-01-15 11:40:55,831 DEBUG k.k.java.study.JUnitAnnotationTest.setupClass : Before Class...
2016-01-15 11:40:55,962 DEBUG k.k.java.study.JUnitAnnotationTest.cleanupClass : After Class...

16. Hamcrest 사용 예

17. AssertJ Core features highlight

18. <dependency>
<groupId>org.assertj</groupId>
<artifactId>assertj-core</artifactId>
<version>3.2.0</version>
<scope>test</scope>
</dependency>
Maven
Gradle
testCompile ‘org.assertj.assertj-core:3.2.0’

19. ImportAssertions class
import static org.assertj.core.api.Assertions.*;
import static org.assertj.core.api.Assertions.assertThat; // Main Assertion
import static org.assertj.core.api.Assertions.atIndex; // 리스트 검증
import static org.assertj.core.api.Assertions.entry; // Map 검증
import static org.assertj.core.api.Assertions.tuple; // 클래스에서 속성 추출 시 사용
import static org.assertj.core.api.Assertions.fail; // 예외 검증 시 사용
import static org.assertj.core.api.Assertions.failBecauseExceptionWasNotThrown;
import static org.assertj.core.api.Assertions.filter; // 컬렉션 필터링
import static org.assertj.core.api.Assertions.offset; // 부동소숫점 수형 관련
import static org.assertj.core.api.Assertions.anyOf; // 컨디션 적용
import static org.assertj.core.api.Assertions.contentOf; // 파일 관련 검증

20. assertThat(cfg.getDatabase()).isNotNull();
assertThat(cfg.getDatabase().getDriverClass().isPresent()).isTrue();
assertThat(cfg.getDatabase().getJdbcUrl().isPresent()).isTrue();
Offset<Double> offset = Assertions.offset(1.0e-8);
assertThat(valueOf("142.milligrams").inGram()).isEqualTo(milligram(142).inGram(), offset);
assertThat(valueOf("0.1.gram").inGram()).isEqualTo(gram(0.1).inGram(), offset);
assertThat(valueOf("10000.1.gram").inGram()).isEqualTo(gram(10000.1).inGram(), offset);
assertThat(valueOf("78.4.kilogram").inGram()).isEqualTo(kilogram(78.4).inGram(), offset);
assertThatThrownBy(() -> valueOf("100.bottles"))
.isInstanceOf(NumberFormatException.class);
assertThatThrownBy(() -> valueOf("100 gram"))
.isInstanceOf(NumberFormatException.class);
assertThatThrownBy(() -> valueOf("100.0.0.0.gram"))
.isInstanceOf(NumberFormatException.class);

21. import static org.assertj.core.api.Assertions.assertThat;
import static org.assertj.core.api.Assertions.fail;
import static org.assertj.core.api.Assertions.failBecauseExceptionWasNotThrown;
// ... 생략
assertThat(fellowshipOfTheRing).hasSize(9);
// 일반적으로 예외 발생에 대한 검증 처리
try {
fellowshipOfTheRing.get(9); // 예외 발생!!!
// 여기까지 코드가 오는 것은 기대했던 예외가 발생하지 않았다는 뜻! 검증 실패
fail("IndexOutOfBoundsException expected because fellowshipOfTheRing has only 9 elements");
} catch (IndexOutOfBoundsException e) {
assertThat(e).hasMessage("Index: 9, Size: 9");
}
// 주의점 : Throwable 로 catch 하면 안된다.
// 그러면 fail로 발생한 AssertionError 도 catch 해서 검증 성공으로 인식해 버린다.
// 다른 방식
try {
fellowshipOfTheRing.get(9); // 예외 발생!!
// 기대했던 예외가 발생하지 않았다는 뜻! 검증 실패
failBecauseExceptionWasNotThrown(IndexOutOfBoundsException.class);
} catch (IndexOutOfBoundsException e) {
assertThat(e).hasMessage("Index: 9, Size: 9");
}
With Java 7

22. @Test
public void testException() {
assertThatThrownBy(() -> { throw new Exception("boom!")
}).isInstanceOf(Exception.class)
.hasMessageContaining("boom");
}
With Java 8
@Test
public void testException() {
// given some preconditions
// …
// when
Throwable thrown = catchThrowable(() -> { throw new Exception("boom!") });
// then
assertThat(thrown).isInstanceOf(Exception.class) .hasMessageContaining("boom");
}
With Java 8 BDD

23. // 두 인스턴스가 같은 배우이고, 속성 중 종족 값만 같은 경우...
// fredo 와 sam 은 다른 사람이지만 같은 호빗족이다.
assertThat(frodo).isNotEqualTo(sam);
// raceComparator 가 Comparator<AClass> 이면서 race 값만 비교하는 경우
assertThat(frodo).usingComparator(raceComparator).isEqualTo(sam);
// 절대반지 그룹에 간달프는 속해있지만, 사우론은 아니다
assertThat(fellowshipOfTheRing).contains(gandalf).doesNotContain(sauron);
// 하지만 종족을 비교하는 raceComparator 를 사용하면 사우론도 간달프와 같은 Maia 종족이다.
assertThat(fellowshipOfTheRing)
.usingElementComparator(raceComparator)
.contains(sauron);
usingElementComparator(Comparator) example:
usingComparator(Comparator) example: