1) In Eclipse (I'm using version 2020-02(4.15.0)), create new Maven project (archetype: groupid: org.apache.maven.archetype, artifactId: maven-archetype-quickstart) 2) Add new StandardDeviationA class (update package name as required):   package com.samplea.drools.DroolsNewTypes5; import java.math.BigDecimal; public class StandardDeviationA { public static BigDecimal stdev_a(java.lang. Number val) { return new BigDecimal(val.doubleValue() * 2); } }   3) Right-click on new project, choose Run As -> Maven Install  4) Copy location of generated .jar file 5) In Business Central, go to Artifacts (click cog in the top right hand corner, choose Artifacts icon) 6) Add new artifact by clicking upload and choosing location of .jar from step 4) 7) Go to the project in Business Central Space (or create new project). 8) In the project, click on Settings tab (top). Go to Dependencies tab (left).  9) Click "Add from repository" link. Add jar as:         group id: com.samplea.drools          artifact ID: DroolsNewTypes5          version 0.0.1-SNAPSHOT            package whitelist: All    Click Save 10) Go to Assets tab (top). Add new Asset. In new asset, add BKM (business knowledge model) element 11) Double click BKM element to go to details. Configure it as follows: function kind: Java (J) class: "com.samplea.drools.DroolsNewTypes5.StandardDeviationA" method signature: "stdev_a(java.lang.Number)"   Click Save button (top) Alerts pane shows the error