Add javadoc generation

Author: enricovianello

pom.xml

@@ -25,6 +25,7 @@
   </scm>
 
   <properties>
+
     <!-- versions -->
     <plugin.enforcer.version>3.5.0</plugin.enforcer.version>
     <plugin.versions.version>2.16.1</plugin.versions.version>
@@ -39,6 +40,7 @@
     <plugin.gpg.version>3.2.5</plugin.gpg.version>
     <plugin.central-publishing.version>0.7.0</plugin.central-publishing.version>
     <plugin.maven-gpg.version>3.2.7</plugin.maven-gpg.version>
+    <plugin.javadoc.version>3.11.2</plugin.javadoc.version>
 
     <junit.version>4.13.2</junit.version>
     <hamcrest.version>1.3</hamcrest.version>
@@ -217,6 +219,24 @@
           </archive>
         </configuration>
       </plugin>
+
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-javadoc-plugin</artifactId>
+        <version>${plugin.javadoc.version}</version>
+        <configuration>
+          <source>17</source>
+          <outputDirectory>${project.build.directory}/javadoc</outputDirectory>
+        </configuration>
+        <executions>
+          <execution>
+            <id>attach-javadocs</id>
+            <goals>
+              <goal>jar</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
     </plugins>
   </build>