Fix & Cleanup of Several SonarQube Issues

src/main/java/nl/dannyj/mistral/MistralClient.java

@@ -251,7 +251,7 @@ public void createChatCompletionStream(@NonNull ChatCompletionRequest request, @
      * @return A new instance of MistralService
      */
     private MistralService buildMistralService() {
-        return new MistralService(this, new HttpService(this));
+        return new MistralService(new HttpService(this.httpClient), this.objectMapper);
     }
 
     /**
@@ -260,7 +260,7 @@ private MistralService buildMistralService() {
      * @return A new instance of OkHttpClient
      */
     private OkHttpClient buildHttpClient(int readTimeoutSeconds, int connectTimeoutSeconds, int writeTimeoutSeconds) {
-        MistralHeaderInterceptor mistralInterceptor = new MistralHeaderInterceptor(this);
+        MistralHeaderInterceptor mistralInterceptor = new MistralHeaderInterceptor(this.getApiKey());
 
         return new OkHttpClient.Builder()
                 .readTimeout(readTimeoutSeconds, TimeUnit.SECONDS)

src/main/java/nl/dannyj/mistral/interceptors/MistralHeaderInterceptor.java

@@ -16,8 +16,6 @@
 
 package nl.dannyj.mistral.interceptors;
 
-import lombok.NonNull;
-import nl.dannyj.mistral.MistralClient;
 import okhttp3.Interceptor;
 import okhttp3.Request;
 import okhttp3.Response;
@@ -27,10 +25,14 @@
 
 public class MistralHeaderInterceptor implements Interceptor {
 
-    private final MistralClient client;
+    private final String apiKey;
 
-    public MistralHeaderInterceptor(@NonNull MistralClient client) {
-        this.client = client;
+    public MistralHeaderInterceptor(@NotNull String apiKey) {
+        if (apiKey == null || apiKey.isBlank()) {
+            throw new IllegalArgumentException("No API key provided in MistralClient");
+        }
+
+        this.apiKey = apiKey;
     }
 
     @NotNull
@@ -39,10 +41,6 @@ public Response intercept(@NotNull Chain chain) throws IOException {
         Request request = chain.request();
         Request.Builder newRequestBuilder = request.newBuilder();
 
-        if (client.getApiKey() == null || client.getApiKey().isBlank()) {
-            throw new IllegalArgumentException("No API key provided in MistralClient");
-        }
-
         if (request.header("Content-Type") == null) {
             newRequestBuilder.addHeader("Content-Type", "application/json");
         }
@@ -52,7 +50,7 @@ public Response intercept(@NotNull Chain chain) throws IOException {
         }
 
         if (request.header("Authorization") == null) {
-            newRequestBuilder.addHeader("Authorization", "Bearer " + client.getApiKey());
+            newRequestBuilder.addHeader("Authorization", "Bearer " + this.apiKey);
         }
 
         Request newRequest = newRequestBuilder.build();

src/main/java/nl/dannyj/mistral/models/completion/message/ChatMessage.java

@@ -52,7 +52,6 @@ public abstract class ChatMessage {
     /**
      * The content of the message. Can be null or a list of content chunks.
      *
-     * @param content The list of content chunks, or null.
      * @return The list of content chunks, or null.
      */
     @Nullable

src/main/java/nl/dannyj/mistral/serialization/ContentChunkListDeserializer.java

@@ -34,7 +34,7 @@
 
 public class ContentChunkListDeserializer extends StdDeserializer<List<ContentChunk>> implements ContextualDeserializer {
 
-    private JsonDeserializer<?> defaultDeserializer;
+    private transient JsonDeserializer<?> defaultDeserializer;
 
     public ContentChunkListDeserializer() {
         this(null);

src/main/java/nl/dannyj/mistral/serialization/ToolChoiceOptionDeserializer.java

@@ -41,16 +41,8 @@ public ToolChoiceOption deserialize(JsonParser jp, DeserializationContext ctxt)
 
         if (token == JsonToken.VALUE_STRING) {
             String enumValue = jp.getText().toUpperCase();
-            try {
-                return ToolChoiceEnum.valueOf(enumValue);
-            } catch (IllegalArgumentException e) {
-                if ("ANY".equalsIgnoreCase(enumValue)) return ToolChoiceEnum.ANY;
-                if ("AUTO".equalsIgnoreCase(enumValue)) return ToolChoiceEnum.AUTO;
-                if ("NONE".equalsIgnoreCase(enumValue)) return ToolChoiceEnum.NONE;
-                if ("REQUIRED".equalsIgnoreCase(enumValue)) return ToolChoiceEnum.REQUIRED;
-
-                throw ctxt.weirdStringException(enumValue, ToolChoiceEnum.class, "Not a valid ToolChoiceEnum value");
-            }
+
+            return ToolChoiceEnum.valueOf(enumValue);
         } else if (token == JsonToken.START_OBJECT) {
             return mapper.readValue(jp, SpecificToolChoice.class);
         }

src/main/java/nl/dannyj/mistral/services/HttpService.java

@@ -17,7 +17,6 @@
 package nl.dannyj.mistral.services;
 
 import lombok.NonNull;
-import nl.dannyj.mistral.MistralClient;
 import nl.dannyj.mistral.exceptions.MistralAPIException;
 import okhttp3.Callback;
 import okhttp3.MediaType;
@@ -37,15 +36,15 @@ public class HttpService {
 
     private static final String API_URL = "https://api.mistral.ai/v1";
 
-    private final MistralClient client;
+    private final OkHttpClient httpClient;
 
     /**
      * Constructor that initializes the HttpService with a provided MistralClient.
      *
-     * @param client The MistralClient to be used for making requests to the Mistral AI API
+     * @param httpClient The OkHttpClient to be used for making requests to the Mistral AI API
      */
-    public HttpService(@NonNull MistralClient client) {
-        this.client = client;
+    public HttpService(@NonNull OkHttpClient httpClient) {
+        this.httpClient = httpClient;
     }
 
     /**
@@ -91,7 +90,6 @@ public void streamPost(@NonNull String urlPath, @NonNull String body, Callback c
                 .url(API_URL + urlPath)
                 .post(RequestBody.create(body, MediaType.parse("application/json")))
                 .build();
-        OkHttpClient httpClient = client.getHttpClient();
 
         httpClient.newCall(request).enqueue(callBack);
     }
@@ -104,8 +102,6 @@ public void streamPost(@NonNull String urlPath, @NonNull String body, Callback c
      * @throws MistralAPIException If the response is not successful, the response body is null or an IOException occurs in the objectmapper
      */
     private String executeRequest(Request request) {
-        OkHttpClient httpClient = client.getHttpClient();
-
         try (Response response = httpClient.newCall(request).execute()) {
             if (!response.isSuccessful()) {
                 throw new MistralAPIException("Received unexpected response code " + response.code() + ": " + (response.body() != null ? response.body().string() : response));

src/main/java/nl/dannyj/mistral/services/MistralService.java

@@ -17,13 +17,13 @@
 package nl.dannyj.mistral.services;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import jakarta.validation.ConstraintViolation;
 import jakarta.validation.ConstraintViolationException;
 import jakarta.validation.Validation;
 import jakarta.validation.Validator;
 import jakarta.validation.ValidatorFactory;
 import lombok.NonNull;
-import nl.dannyj.mistral.MistralClient;
 import nl.dannyj.mistral.exceptions.InvalidJsonException;
 import nl.dannyj.mistral.exceptions.UnexpectedResponseEndException;
 import nl.dannyj.mistral.exceptions.UnexpectedResponseException;
@@ -55,17 +55,17 @@
 public class MistralService {
 
     private final HttpService httpService;
-    private final MistralClient client;
+    private final ObjectMapper objectMapper;
     private final Validator validator;
 
     /**
      * Constructor that initializes the MistralService with a provided MistralClient and HttpService.
      *
-     * @param client      The MistralClient to be used for interacting with the Mistral AI API
-     * @param httpService The HttpService to be used for making HTTP requests
+     * @param httpService The HttpService to be used for making HTTP requests to the Mistral AI API
+     * @param objectMapper The ObjectMapper to be used for converting objects to and from JSON
      */
-    public MistralService(@NonNull MistralClient client, @NonNull HttpService httpService) {
-        this.client = client;
+    public MistralService(@NonNull HttpService httpService, @NonNull ObjectMapper objectMapper) {
+        this.objectMapper = objectMapper;
         this.httpService = httpService;
 
         try (ValidatorFactory validatorFactory = Validation.buildDefaultValidatorFactory()) {
@@ -118,7 +118,7 @@ public void createChatCompletionStream(@NonNull ChatCompletionRequest request, @
         validateRequest(request);
 
         try {
-            String requestJson = client.getObjectMapper().writeValueAsString(request);
+            String requestJson = this.objectMapper.writeValueAsString(request);
 
             httpService.streamPost("/chat/completions", requestJson, new Callback() {
                 @Override
@@ -161,7 +161,7 @@ public ListModelsResponse listModels() {
         String response = httpService.get("/models");
 
         try {
-            return client.getObjectMapper().readValue(response, ListModelsResponse.class);
+            return this.objectMapper.readValue(response, ListModelsResponse.class);
         } catch (JsonProcessingException e) {
             throw new UnexpectedResponseException("Received unexpected response from the Mistral.ai API (mistral-java-client might need to be updated): " + response, e);
         }
@@ -238,15 +238,15 @@ private <T extends Request, U extends Response> U postRequest(String endpoint, T
         String requestJson = null;
 
         try {
-            requestJson = client.getObjectMapper().writeValueAsString(request);
+            requestJson = this.objectMapper.writeValueAsString(request);
         } catch (JsonProcessingException e) {
             throw new InvalidJsonException("Failed to convert request to JSON", e);
         }
 
         try {
             response = httpService.post(endpoint, requestJson);
 
-            return client.getObjectMapper().readValue(response, responseType);
+            return this.objectMapper.readValue(response, responseType);
         } catch (JsonProcessingException e) {
             throw new UnexpectedResponseException("Received unexpected response from the Mistral.ai API (mistral-java-client might need to be updated): " + response, e);
         }
@@ -266,7 +266,7 @@ private void handleResponseBody(@NotNull ResponseBody responseBody, ChatCompleti
                 }
 
                 try {
-                    MessageChunk messageChunk = client.getObjectMapper().readValue(chunk, MessageChunk.class);
+                    MessageChunk messageChunk = this.objectMapper.readValue(chunk, MessageChunk.class);
 
                     callback.onChunkReceived(messageChunk);
                 } catch (JsonProcessingException e) {