Replace the chain of if/else with a switch expression.

pom.xml

@@ -17,10 +17,10 @@
   <properties>
     <java.version>25</java.version>
     <jacoco-maven-plugin.version>0.8.14</jacoco-maven-plugin.version>
-    <maven-checkstyle-plugin.version>3.5.0</maven-checkstyle-plugin.version>
-    <checkstyle.version>10.6.0</checkstyle.version>
+    <maven-checkstyle-plugin.version>3.6.0</maven-checkstyle-plugin.version>
+    <checkstyle.version>12.1.2</checkstyle.version>
     <lifecycle-mapping.version>1.0.0</lifecycle-mapping.version>
-    <jjwt.version>0.12.6</jjwt.version>
+    <jjwt.version>0.13.0</jjwt.version>
     <okhttp.version>5.3.2</okhttp.version>
   </properties>
   <organization>
@@ -91,6 +91,13 @@
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-checkstyle-plugin</artifactId>
           <version>${maven-checkstyle-plugin.version}</version>
+          <dependencies>
+            <dependency>
+              <groupId>com.puppycrawl.tools</groupId>
+              <artifactId>checkstyle</artifactId>
+              <version>${checkstyle.version}</version>
+            </dependency>
+          </dependencies>           
         </plugin>
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>

xapi-client/src/main/java/dev/learning/xapi/client/StatementHttpMessageWriter.java

@@ -164,14 +164,16 @@ private List<Object> getParts(Object object) {
 
     final var list = new ArrayList<>();
 
-    Stream<Attachment> attachments;
-    if (object instanceof final Statement statement) {
-      attachments = getRealAttachments(statement);
-    } else if (object instanceof final List<?> statements
-        && !statements.isEmpty()
-        && statements.get(0) instanceof Statement) {
-      attachments = ((List<Statement>) statements).stream().flatMap(this::getRealAttachments);
-    } else {
+    final Stream<Attachment> attachments =
+        switch (object) {
+          case Statement statement -> getRealAttachments(statement);
+          case List<?> statements
+              when !statements.isEmpty() && statements.get(0) instanceof Statement ->
+                  ((List<Statement>) statements).stream().flatMap(this::getRealAttachments);
+          default -> null;
+        };
+
+    if (attachments == null) {
       // The object is not a statement or list of statements
       return list;
     }

xapi-client/src/test/java/dev/learning/xapi/client/configuration/XapiClientAutoConfigurationAuthorizationTest.java

@@ -49,7 +49,7 @@ public void accept(Builder builder) {
       mockWebServer = new MockWebServer();
       try {
         mockWebServer.start();
-      } catch (final IOException e) {
+      } catch (final IOException _) {
         // Ignore - test will fail if server doesn't start
       }
       builder.baseUrl(mockWebServer.url("").toString());

xapi-client/src/test/java/dev/learning/xapi/client/configuration/XapiClientAutoConfigurationUsernamePasswordTest.java

@@ -49,7 +49,7 @@ public void accept(Builder builder) {
       mockWebServer = new MockWebServer();
       try {
         mockWebServer.start();
-      } catch (final IOException e) {
+      } catch (final IOException _) {
         // Ignore - test will fail if server doesn't start
       }
       builder.baseUrl(mockWebServer.url("").toString());

xapi-model/src/main/java/dev/learning/xapi/jackson/StrictLocaleDeserializer.java

@@ -53,7 +53,7 @@ static Locale validateLocale(String localeString, DeserializationContext deseria
       // test validity of language and country codes (throws exception)
       locale.getISO3Language();
       locale.getISO3Country();
-    } catch (final MissingResourceException e) {
+    } catch (final MissingResourceException _) {
       locale = null;
     }
     // test the validity of the whole key