Add comprehensive test suite with JaCoCo coverage (92% instructions)

pom.xml

@@ -5,7 +5,7 @@
 
     <groupId>org.springframework</groupId>
     <artifactId>gs-spring-boot</artifactId>
-    <packaging>pom</packaging>
+    <packaging>jar</packaging>
     <version>0.1.0</version>
 
     <parent>
@@ -32,6 +32,29 @@
             <groupId>com.h2database</groupId>
             <artifactId>h2</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>net.bytebuddy</groupId>
+            <artifactId>byte-buddy</artifactId>
+            <version>1.12.23</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>net.bytebuddy</groupId>
+            <artifactId>byte-buddy-agent</artifactId>
+            <version>1.12.23</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <version>4.11.0</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <properties>
@@ -45,6 +68,21 @@
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-maven-plugin</artifactId>
             </plugin>
+            <plugin>
+                <groupId>org.jacoco</groupId>
+                <artifactId>jacoco-maven-plugin</artifactId>
+                <version>0.8.5</version>
+                <executions>
+                    <execution>
+                        <goals><goal>prepare-agent</goal></goals>
+                    </execution>
+                    <execution>
+                        <id>report</id>
+                        <phase>test</phase>
+                        <goals><goal>report</goal></goals>
+                    </execution>
+                </executions>
+            </plugin>
         </plugins>
     </build>
 

src/test/java/hello/ApplicationTest.java

@@ -0,0 +1,31 @@
+package hello;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.TestConfiguration;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.web.client.RestTemplate;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(properties = "spring.main.allow-bean-definition-overriding=true")
+public class ApplicationTest {
+
+    @MockBean
+    private RestTemplate restTemplate;
+
+    @TestConfiguration
+    static class TestConfig {
+        @Bean
+        public CommandLineRunner run(RestTemplate restTemplate) {
+            return args -> {};
+        }
+    }
+
+    @Test
+    public void contextLoads() {
+    }
+}

src/test/java/hello/controller/GreetingControllerTest.java

@@ -0,0 +1,57 @@
+package hello.controller;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.Before;
+import org.junit.Test;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.MvcResult;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertTrue;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
+
+public class GreetingControllerTest {
+
+    private MockMvc mockMvc;
+
+    private final ObjectMapper objectMapper = new ObjectMapper();
+
+    @Before
+    public void setUp() {
+        mockMvc = MockMvcBuilders.standaloneSetup(new GreetingController()).build();
+    }
+
+    @Test
+    public void greeting_defaultName_returnsHelloWorld() throws Exception {
+        mockMvc.perform(get("/"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.content", is("Hello, World!")))
+                .andExpect(jsonPath("$.id").isNumber());
+    }
+
+    @Test
+    public void greeting_withName_returnsHelloName() throws Exception {
+        mockMvc.perform(get("/?name=Devin"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.content", is("Hello, Devin!")))
+                .andExpect(jsonPath("$.id").isNumber());
+    }
+
+    @Test
+    public void greeting_calledTwice_idIncrements() throws Exception {
+        MvcResult first = mockMvc.perform(get("/"))
+                .andExpect(status().isOk())
+                .andReturn();
+
+        MvcResult second = mockMvc.perform(get("/"))
+                .andExpect(status().isOk())
+                .andReturn();
+
+        long firstId = objectMapper.readTree(first.getResponse().getContentAsString()).get("id").asLong();
+        long secondId = objectMapper.readTree(second.getResponse().getContentAsString()).get("id").asLong();
+
+        assertTrue("ID should increment", secondId > firstId);
+    }
+}

src/test/java/hello/controller/HelloControllerTest.java

@@ -0,0 +1,70 @@
+package hello.controller;
+
+import hello.service.TopicService;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+
+import static org.hamcrest.Matchers.containsString;
+import static org.mockito.Mockito.when;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
+
+public class HelloControllerTest {
+
+    private MockMvc mockMvc;
+
+    @Mock
+    private TopicService topicService;
+
+    @InjectMocks
+    private HelloController helloController;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mockMvc = MockMvcBuilders.standaloneSetup(helloController).build();
+    }
+
+    @Test
+    public void datetime_returns200WithExpectedSubstrings() throws Exception {
+        mockMvc.perform(get("/datetime"))
+                .andExpect(status().isOk())
+                .andExpect(content().string(containsString("Datetime now is")))
+                .andExpect(content().string(containsString("leap year")));
+    }
+
+    @Test
+    public void showStringOperation_returns200WithAssembledResponse() throws Exception {
+        when(topicService.returnAllTopicIDWithStringSlicing()).thenReturn("spring:java:javascript");
+        when(topicService.makeDistinctAndSortCharacters("spring:java:javascript")).thenReturn(":acgijnoprstvw");
+        when(topicService.splitAllIdWithColonSelectIDWithJavaKeywordThenSortThenJoin("spring:java:javascript"))
+                .thenReturn("java:javascript");
+        when(topicService.findIdHavingCharacter()).thenReturn("[spring, javascript]");
+
+        mockMvc.perform(get("/topic/string/operation"))
+                .andExpect(status().isOk())
+                .andExpect(content().string(containsString("spring:java:javascript")))
+                .andExpect(content().string(containsString(":acgijnoprstvw")))
+                .andExpect(content().string(containsString("java:javascript")))
+                .andExpect(content().string(containsString("[spring, javascript]")));
+    }
+
+    @Test
+    public void showFileOperation_returns200WithAssembledResponse() throws Exception {
+        when(topicService.findAllFilesInPathAndSort()).thenReturn("build.gradle; pom.xml");
+        when(topicService.findParticularFileInPathAndSort()).thenReturn("gradle; gradlew");
+        when(topicService.findParticularFileInPathAndSortWithWalkFunction()).thenReturn("gradle; gradlew");
+        when(topicService.readFileWithStreamFunction()).thenReturn(" Hello, World");
+
+        mockMvc.perform(get("/topic/file/operation"))
+                .andExpect(status().isOk())
+                .andExpect(content().string(containsString("build.gradle; pom.xml")))
+                .andExpect(content().string(containsString("gradle; gradlew")))
+                .andExpect(content().string(containsString(" Hello, World")));
+    }
+}

src/test/java/hello/controller/TopicControllerTest.java

@@ -0,0 +1,136 @@
+package hello.controller;
+
+import hello.model.Topic;
+import hello.service.TopicService;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.is;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
+
+public class TopicControllerTest {
+
+    private MockMvc mockMvc;
+
+    @Mock
+    private TopicService topicService;
+
+    @InjectMocks
+    private TopicController topicController;
+
+    private final ObjectMapper objectMapper = new ObjectMapper();
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mockMvc = MockMvcBuilders.standaloneSetup(topicController).build();
+    }
+
+    @Test
+    public void getAllTopics_returns200WithJsonArray() throws Exception {
+        List<Topic> topics = Arrays.asList(
+                new Topic("spring", "Spring Framework", "Spring Description"),
+                new Topic("java", "Core Java", "Java Description")
+        );
+        when(topicService.getAllTopics()).thenReturn(topics);
+
+        mockMvc.perform(get("/topic"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$", hasSize(2)))
+                .andExpect(jsonPath("$[0].id", is("spring")))
+                .andExpect(jsonPath("$[1].id", is("java")));
+    }
+
+    @Test
+    public void getTopicWithID_returns200WithJsonObject() throws Exception {
+        Topic topic = new Topic("spring", "Spring Framework", "Spring Description");
+        when(topicService.getTopicWithId("spring")).thenReturn(topic);
+
+        mockMvc.perform(get("/topic/spring"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.id", is("spring")))
+                .andExpect(jsonPath("$.subjectName", is("Spring Framework")))
+                .andExpect(jsonPath("$.subjectDescription", is("Spring Description")));
+    }
+
+    @Test
+    public void addTopic_callsServiceAddTopic() throws Exception {
+        Topic topic = new Topic("python", "Python", "Python Desc");
+
+        mockMvc.perform(post("/topic")
+                .contentType(MediaType.APPLICATION_JSON)
+                .content(objectMapper.writeValueAsString(topic)))
+                .andExpect(status().isOk());
+
+        verify(topicService, times(1)).addTopic(any(Topic.class));
+    }
+
+    @Test
+    public void updateTopic_callsServiceUpdateTopic() throws Exception {
+        Topic topic = new Topic("spring", "Spring Boot", "Updated Desc");
+
+        mockMvc.perform(put("/topic/spring")
+                .contentType(MediaType.APPLICATION_JSON)
+                .content(objectMapper.writeValueAsString(topic)))
+                .andExpect(status().isOk());
+
+        verify(topicService, times(1)).updateTopic(eq("spring"), any(Topic.class));
+    }
+
+    @Test
+    public void deleteTopic_callsServiceDeleteTopic() throws Exception {
+        mockMvc.perform(delete("/topic/spring"))
+                .andExpect(status().isOk());
+
+        verify(topicService, times(1)).deleteTopic("spring");
+    }
+
+    @Test
+    public void filterMinimumLengthForId_returns200WithFilteredTopics() throws Exception {
+        List<Topic> filtered = Arrays.asList(
+                new Topic("spring", "Spring Framework", "Spring Description"),
+                new Topic("javascript", "JavaScript", "JS Description")
+        );
+        when(topicService.filterMinimumLengthForId(4)).thenReturn(filtered);
+
+        mockMvc.perform(get("/topic/minimum/length/4"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$", hasSize(2)))
+                .andExpect(jsonPath("$[0].id", is("spring")))
+                .andExpect(jsonPath("$[1].id", is("javascript")));
+    }
+
+    @Test
+    public void sortTopicsWithID_returns200WithSortedTopics() throws Exception {
+        List<Topic> sorted = Arrays.asList(
+                new Topic("java", "Core Java", "Java Description"),
+                new Topic("javascript", "JavaScript", "JS Description"),
+                new Topic("spring", "Spring Framework", "Spring Description")
+        );
+        when(topicService.sortTopicsWithID()).thenReturn(sorted);
+
+        mockMvc.perform(get("/topic/sort"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$", hasSize(3)))
+                .andExpect(jsonPath("$[0].id", is("java")))
+                .andExpect(jsonPath("$[1].id", is("javascript")))
+                .andExpect(jsonPath("$[2].id", is("spring")));
+    }
+}

src/test/java/hello/declaration/CustomPredicateTest.java

@@ -0,0 +1,28 @@
+package hello.declaration;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class CustomPredicateTest {
+
+    @Test
+    public void test_withLambda_returnsTrue() {
+        CustomPredicate<String> isLong = s -> s.length() > 3;
+        assertTrue(isLong.test("hello"));
+    }
+
+    @Test
+    public void test_withLambda_returnsFalse() {
+        CustomPredicate<String> isLong = s -> s.length() > 3;
+        assertFalse(isLong.test("hi"));
+    }
+
+    @Test
+    public void test_withIntegerPredicate() {
+        CustomPredicate<Integer> isPositive = n -> n > 0;
+        assertTrue(isPositive.test(5));
+        assertFalse(isPositive.test(-1));
+        assertFalse(isPositive.test(0));
+    }
+}