I can fix it! Nice @perwramdemark, go ahead! Related to https://github.com/iluwatar/java-design-patterns/issues/944
WARNING when building project
When building project with mvn install you get below warning. You need to setup the JXR plugin to get ride of this for multi-module projects.

[INFO] --- maven-pmd-plugin:3.6:pmd (pmd) @ abstract-factory ---
[WARNING] Unable to locate Source XRef to link to - DISABLED
Unable to locate Source XRef to link to - DISABLED
pom.xml
pom.xml
diff --git a/pom.xml b/pom.xml
index d985b6c62fe2..874bf66dddee 100644
--- a/pom.xml
+++ b/pom.xml
@@ -465,6 +465,11 @@
                 <artifactId>maven-pmd-plugin</artifactId>
                 <version>${pmd.version}</version>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-jxr-plugin</artifactId>
+                <version>3.0.0</version>
+            </plugin>
         </plugins>
     </reporting>
 
