1 package de.juplo.kafka;
3 import org.junit.jupiter.api.DisplayName;
4 import org.junit.jupiter.api.Test;
5 import org.junit.jupiter.params.ParameterizedTest;
6 import org.junit.jupiter.params.provider.Arguments;
7 import org.junit.jupiter.params.provider.MethodSource;
8 import org.junit.jupiter.params.provider.ValueSource;
10 import java.util.Arrays;
11 import java.util.stream.IntStream;
12 import java.util.stream.Stream;
14 import static org.assertj.core.api.Assertions.*;
17 public class SumBusinessLogicTest
20 @DisplayName("A new sum can be started, if it does not exist")
21 public void testCanStartSumIfNotExists()
23 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
24 assertThatNoException().isThrownBy(() -> sumBusinessLogic.startSum("foo"));
28 @DisplayName("Starting an already existing sum again, causes an IllegalStateException")
29 public void testStartSumCausesExceptionIfExists()
31 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
32 sumBusinessLogic.startSum("foo");
33 assertThatIllegalStateException().isThrownBy(() -> sumBusinessLogic.startSum("foo"));
37 @DisplayName("An empty Optional should be returned, for a non-existing sum")
38 public void testEmptyOptionalForNonExistingSum()
40 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
41 assertThat(sumBusinessLogic.getSum("foo")).isEmpty();
45 @DisplayName("A non-empty Optional should be returned, for an existing sum")
46 public void testNonEmptyOptionalForExistingSum()
48 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
49 sumBusinessLogic.startSum("foo");
50 assertThat(sumBusinessLogic.getSum("foo")).isNotEmpty();
54 @DisplayName("A sum can be ended, if it does exist")
55 public void testCanEndIfSumExists()
57 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
58 sumBusinessLogic.startSum("foo");
59 assertThatNoException().isThrownBy(() -> sumBusinessLogic.endSum("foo"));
63 @DisplayName("An existing Sum returns a non-null value, if ended")
64 public void testEndSumReturnsNonNullValueIfSumExists()
66 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
67 sumBusinessLogic.startSum("foo");
68 assertThat(sumBusinessLogic.endSum("foo")).isNotNull();
72 @DisplayName("An existing Sum returns a non-negative value, if ended")
73 public void testEndSumReturnsNonNegativeValueIfSumExists()
75 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
76 sumBusinessLogic.startSum("foo");
77 assertThat(sumBusinessLogic.endSum("foo")).isNotNegative();
81 @DisplayName("Ending a non-existing sum, causes an IllegalStateException")
82 public void testEndSumCausesExceptionIfNotExists()
84 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
85 assertThatIllegalStateException().isThrownBy(() -> sumBusinessLogic.endSum("foo"));
89 @DisplayName("Adding to a non-existent sum causes an IllegalStateException")
90 public void testAddToSumCausesExceptionIfNotExists()
92 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
93 assertThatIllegalStateException().isThrownBy(() -> sumBusinessLogic.addToSum("foo", 1));
97 @DisplayName("Adding a null-value to an existing sum causes an IllegalArgumentException")
98 public void testAddNullToExistingSumCausesException()
100 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
101 sumBusinessLogic.startSum("foo");
102 assertThatIllegalArgumentException().isThrownBy(() -> sumBusinessLogic.addToSum("foo", null));
105 @ParameterizedTest(name = "{index}: Adding {0}")
106 @DisplayName("Adding a non-positive value to an existing sum causes an IllegalArgumentException")
107 @ValueSource(ints = { 0, -1, -6, -66, Integer.MIN_VALUE })
108 public void testAddingNonPositiveValueToExistingSumCausesException(int value)
110 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
111 sumBusinessLogic.startSum("foo");
112 assertThatIllegalArgumentException().isThrownBy(() -> sumBusinessLogic.addToSum("foo", value));
116 @DisplayName("Can add a positive value to an existing sum")
117 public void testCanAddPositiveValueToExistingSum()
119 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
120 sumBusinessLogic.startSum("foo");
121 assertThatIllegalArgumentException().isThrownBy(() -> sumBusinessLogic.addToSum("foo", -1));
124 @ParameterizedTest(name = "{index}: Summing up {0}")
125 @DisplayName("Adds up numbers correctly")
126 @MethodSource("numbersProvider")
127 public void testCanAddPositiveValueToExistingSum(int... numbers)
129 long expectedResult = Arrays.stream(numbers).sum();
130 SumBusinessLogic sumBusinessLogic = new SumBusinessLogic();
131 sumBusinessLogic.startSum("foo");
132 Arrays.stream(numbers).forEach(number -> sumBusinessLogic.addToSum("foo", number));
133 assertThat(sumBusinessLogic.endSum("foo")).isEqualTo(expectedResult);
136 static Stream<Arguments> numbersProvider() {
138 Arguments.of((Object) IntStream.rangeClosed(1,9).toArray()),
139 Arguments.of((Object) IntStream.rangeClosed(1,19).toArray()),
140 Arguments.of((Object) IntStream.rangeClosed(1,66).toArray()));