All Test Case:

jackson-datatype-problem/src/main/java/module-info.java

@@ -4,6 +4,7 @@
     requires transitive com.fasterxml.jackson.core;
     requires transitive com.fasterxml.jackson.databind;
     requires transitive org.zalando.problem;
+    requires org.checkerframework.checker.qual;
     exports org.zalando.problem.jackson;
     provides com.fasterxml.jackson.databind.Module with org.zalando.problem.jackson.ProblemModule;
 }

jackson-datatype-problem/src/test/java/org/zalando/problem/jackson/MyTest.java

@@ -0,0 +1,116 @@
+package org.zalando.problem.jackson;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.zalando.problem.Status;
+import org.zalando.problem.StatusType;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertInstanceOf;
+
+public class MyTest {
+
+    @Test
+    @DisplayName("11.1 Input Status Code is in the Map")
+    void TestDeserializeWithKnownStatusCode() throws IOException {
+        Map<Integer, StatusType> statusMap = new HashMap<>();
+        statusMap.put(400, Status.BAD_REQUEST);
+
+        StatusTypeDeserializer deserializer = new StatusTypeDeserializer(statusMap);
+        ObjectMapper mapper = new ObjectMapper();
+
+        SimpleModule module = new SimpleModule();
+        module.addDeserializer(StatusType.class, deserializer);
+        mapper.registerModule(module);
+
+        StatusType result = mapper.readValue("400", StatusType.class);
+
+        assertEquals(Status.BAD_REQUEST, result);
+        assertEquals(400, result.getStatusCode());
+        assertEquals("Bad Request", result.getReasonPhrase());
+    }
+
+    @Test
+    @DisplayName("11.2 Multiple Input Status Code is in the Map")
+    void TestDeserializeWithMultipleKnownStatusCodes() throws IOException {
+        Map<Integer, StatusType> statusMap = new HashMap<>();
+        statusMap.put(200, Status.OK);
+        statusMap.put(402, Status.PAYMENT_REQUIRED);
+        statusMap.put(500, Status.INTERNAL_SERVER_ERROR);
+
+        StatusTypeDeserializer deserializer = new StatusTypeDeserializer(statusMap);
+        ObjectMapper mapper = new ObjectMapper();
+
+        SimpleModule module = new SimpleModule();
+        module.addDeserializer(StatusType.class, deserializer);
+        mapper.registerModule(module);
+
+        StatusType result200 = mapper.readValue("200", StatusType.class);
+        assertEquals(Status.OK, result200);
+        assertEquals(200, result200.getStatusCode());
+        assertEquals("OK", result200.getReasonPhrase());
+
+        StatusType result402 = mapper.readValue("402", StatusType.class);
+        assertEquals(Status.PAYMENT_REQUIRED, result402);
+        assertEquals(402, result402.getStatusCode());
+        assertEquals("Payment Required", result402.getReasonPhrase());
+
+        StatusType result500 = mapper.readValue("500", StatusType.class);
+        assertEquals(Status.INTERNAL_SERVER_ERROR, result500);
+        assertEquals(500, result500.getStatusCode());
+        assertEquals("Internal Server Error", result500.getReasonPhrase());
+    }
+
+
+    @Test
+    @DisplayName("11.3 Input Status Code is not in the Map")
+    void TestDeserializeWithUnknownStatusCode() throws IOException {
+        Map<Integer, StatusType> statusMap = new HashMap<>();
+        statusMap.put(400, Status.BAD_REQUEST);
+
+        StatusTypeDeserializer deserializer = new StatusTypeDeserializer(statusMap);
+        ObjectMapper mapper = new ObjectMapper();
+
+        SimpleModule module = new SimpleModule();
+        module.addDeserializer(StatusType.class, deserializer);
+        mapper.registerModule(module);
+
+        StatusType result1 = mapper.readValue("404", StatusType.class);
+        StatusType result2 = mapper.readValue("500", StatusType.class);
+
+        assertEquals(404, result1.getStatusCode());
+        assertEquals("Unknown", result1.getReasonPhrase());
+        assertInstanceOf(UnknownStatus.class, result1);
+        assertEquals(500, result2.getStatusCode());
+        assertEquals("Unknown", result2.getReasonPhrase());
+        assertInstanceOf(UnknownStatus.class, result2);
+    }
+
+    @Test
+    @DisplayName("11.4 The Map is empty")
+    void TestDeserializeWithEmptyMap() throws IOException {
+        Map<Integer, StatusType> emptyMap = new HashMap<>();
+
+        StatusTypeDeserializer deserializer = new StatusTypeDeserializer(emptyMap);
+        ObjectMapper mapper = new ObjectMapper();
+
+        SimpleModule module = new SimpleModule();
+        module.addDeserializer(StatusType.class, deserializer);
+        mapper.registerModule(module);
+
+        StatusType result = mapper.readValue("200", StatusType.class);
+
+        assertEquals(200, result.getStatusCode());
+        assertEquals("Unknown", result.getReasonPhrase());
+        assertInstanceOf(UnknownStatus.class, result);
+    }
+}

pom.xml

@@ -47,8 +47,8 @@
     </distributionManagement>
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.8</maven.compiler.target>
+        <maven.compiler.source>23</maven.compiler.source>
+        <maven.compiler.target>23</maven.compiler.target>
         <junit-jupiter.version>5.8.2</junit-jupiter.version>
     </properties>
     <dependencyManagement>

problem/pom.xml

@@ -10,4 +10,12 @@
     </parent>
     <artifactId>problem</artifactId>
     <description>An implementation of the application/problem+json draft.</description>
+    <dependencies>
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+            <version>2.9.0</version>
+            <scope>compile</scope>
+        </dependency>
+    </dependencies>
 </project>

problem/src/main/java/module-info.java

@@ -2,4 +2,6 @@
     requires static org.apiguardian.api;
     requires transitive com.google.gson;
     exports org.zalando.problem;
+    requires org.checkerframework.checker.qual;
+    uses org.zalando.problem.spi.StackTraceProcessor;
 }