code: @Override
      public JDocCommentable apply(String nodeName, JsonNode node, JsonNode parent, JDocCommentable generatableType, Schema schema) {
  
          // Since NotRequiredRule is executed for all fields that do not have "required" present,
          // we need to recognize whether the field is part of the RequiredArrayRule.
          JsonNode requiredArray = schema.getContent().get("required");
  
          if (requiredArray != null) {
              for (Iterator<JsonNode> iterator = requiredArray.elements(); iterator.hasNext(); ) {
                  String requiredArrayItem = iterator.next().asText();
                  if (nodeName.equals(requiredArrayItem)) {
                      return generatableType;
                  }
              }
          }
  
          if (ruleFactory.getGenerationConfig().isIncludeJsr305Annotations()
                  && generatableType instanceof JFieldVar) {
              generatableType.javadoc().append(NOT_REQUIRED_COMMENT_TEXT);
              ((JFieldVar) generatableType).annotate(Nullable.class);
          }
  
          return generatableType;
      }
docs: Applies this schema rule to take the not required code generation steps.
  <p>
  The not required rule adds a Nullable annotation if JSR-305 annotations are desired.
  
  @param nodeName
  the name of the schema node for which this "required" rule has
  been added
  @param node
  the "not required" node, having a value <code>false</code> or
  <code>no value</code>
  @param parent
  the parent node
  @param generatableType
  the class or method which may be marked as "not required"
  @return the JavaDoc comment attached to the generatableType, which
  <em>may</em> have an added not to mark this construct as
  not required.