diff --git a/config/checkstyle.xml b/config/checkstyle.xml
index 4a7d038..424bac8 100644
--- a/config/checkstyle.xml
+++ b/config/checkstyle.xml
@@ -39,7 +39,7 @@
         <property name="basedir" value="${basedir}"/>
     -->
 
-    <property name="fileExtensions" value="java" />
+    <property name="fileExtensions" value="java"/>
 
     <!-- Checks whether files end with a new line.                        -->
     <!-- See http://checkstyle.sf.net/config_misc.html#NewlineAtEndOfFile -->
@@ -67,18 +67,18 @@
     <module name="TreeWalker">
 
         <!-- Checks for Javadoc comments.                     -->
-        <!-- See http://checkstyle.sf.net/config_javadoc.html -->
+        <!-- See https://checkstyle.sourceforge.io/checks/javadoc/javadocmethod.html -->
         <module name="JavadocMethod">
-        <property name="scope" value="protected"/>
+            <property name="accessModifiers" value="protected"/>
         </module>
         <module name="JavadocType">
-        <property name="scope" value="protected"/>
+            <property name="scope" value="protected"/>
         </module>
         <module name="JavadocVariable">
-        <property name="scope" value="protected"/>
+            <property name="scope" value="protected"/>
         </module>
         <module name="JavadocStyle">
-        <property name="scope" value="protected"/>
+            <property name="scope" value="protected"/>
         </module>
 
         <!-- Checks for Naming Conventions.                  -->
diff --git a/pom.xml b/pom.xml
index 2cf1144..81478d2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -210,7 +210,7 @@
                 <plugin>
                     <groupId>org.apache.maven.plugins</groupId>
                     <artifactId>maven-checkstyle-plugin</artifactId>
-                    <version>3.1.1</version>
+                    <version>3.3.1</version>
                     <configuration>
                         <configLocation>config/checkstyle.xml</configLocation>
                         <encoding>UTF-8</encoding>
diff --git a/src/main/java/pl/szczepanik/silencio/processors/visitors/AbstractJacksonVisitor.java b/src/main/java/pl/szczepanik/silencio/processors/visitors/AbstractJacksonVisitor.java
index 2178bc1..00f7194 100644
--- a/src/main/java/pl/szczepanik/silencio/processors/visitors/AbstractJacksonVisitor.java
+++ b/src/main/java/pl/szczepanik/silencio/processors/visitors/AbstractJacksonVisitor.java
@@ -14,8 +14,13 @@
  * @author Damian Szczepanik (damianszczepanik@github)
  */
 public abstract class AbstractJacksonVisitor extends AbstractVisitor {
-    
-    @SuppressWarnings("unchecked")
+
+    /**
+     * Process map or array/list objects.
+     *
+     * @param key   key
+     * @param value value that should be converted
+     */
     protected void processComplex(String key, Object value) {
         if (isMap(value)) {
             processMap((Map<String, Object>) value);
@@ -26,6 +31,11 @@ protected void processComplex(String key, Object value) {
         }
     }
 
+    /**
+     * Process map object.
+     *
+     * @param map value that should be converted
+     */
     protected void processMap(Map<String, Object> map) {
         for (Map.Entry<String, Object> keyMap : map.entrySet()) {
             String key = keyMap.getKey();
@@ -39,6 +49,11 @@ protected void processMap(Map<String, Object> map) {
         }
     }
 
+    /**
+     * Process array/list object.
+     *
+     * @param list value that should be converted
+     */
     private void processArray(String key, List<Object> list) {
         for (int i = 0; i < list.size(); i++) {
             Object value = list.get(i);