reduce code smells

src/main/java/codes/thischwa/cf/CfBasicHttpClient.java

@@ -48,12 +48,12 @@ abstract class CfBasicHttpClient {
   }
 
   private ObjectMapper initObjectMapper() {
-    ObjectMapper objectMapper = new ObjectMapper();
+    ObjectMapper mapper = new ObjectMapper();
-    objectMapper.registerModule(new JavaTimeModule());
+    mapper.registerModule(new JavaTimeModule());
-    objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
+    mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
-    objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
+    mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
-    objectMapper.setPropertyNamingStrategy(PropertyNamingStrategies.SNAKE_CASE);
+    mapper.setPropertyNamingStrategy(PropertyNamingStrategies.SNAKE_CASE);
-    return objectMapper;
+    return mapper;
   }
 
   private CloseableHttpClient createHttpClient() {

src/main/java/codes/thischwa/cf/CfRequest.java

@@ -52,7 +52,7 @@ public enum CfRequest {
    */
   RECORD_DELETE("/zones/%s/dns_records/%s");
 
-  private static final char varIdentification = '%';
+  private static final char VAR_IDENTIFICATION = '%';
   private final String path;
 
   CfRequest(String path) {
@@ -68,7 +68,7 @@ public enum CfRequest {
    * @return the fully constructed API endpoint path as a string.
    */
   String buildPath(Object... vars) {
-    long varCount = path.chars().filter(c -> c == varIdentification).count();
+    long varCount = path.chars().filter(c -> c == VAR_IDENTIFICATION).count();
     if (varCount != vars.length) {
       throw new IllegalArgumentException(
           String.format(

src/main/java/codes/thischwa/cf/model/AbstractMultipleResponse.java

@@ -39,7 +39,7 @@ public abstract class AbstractMultipleResponse<T extends ResponseEntity> extends
    * constructor of the superclass {@code AbstractResponse}. This constructor is typically used for
    * deserialization or subclass instantiation.
    */
-  public AbstractMultipleResponse() {
+  AbstractMultipleResponse() {
     super();
   }
 }