if (!(connProp instanceof ListProperty))
{
throw new RuntimeException("Expecting " + connProp.name() + " to be a list property");
}
// the connection is of type 1xn
ElementList<?> connList = srcElement.property((ListProperty)connProp);
Element newElement = connList.insert();
setModelProperty(newElement, ((ModelPath.PropertySegment)this.endpoint2Path.head()).getPropertyName(), endpoint2Value);
StandardDiagramConnectionPart newConn = getConnectionPart(srcElement, newElement);
if (newConn == null) {
newConn = createNewConnectionPart(newElement, null);