public static boolean isOptional(Property property) {
	return isZero(property.getLowerValue());
}

import org.eclipse.papyrusrt.umlrt.uml.UMLRTCapsulePart;
import org.eclipse.papyrusrt.umlrt.uml.UMLRTCapsulePartKind;

...

Property p = ...;
UMLRTCapsulePart part = UMLRTCapsulePart.getInstance( p );
if (part.getKind().equals(UMLRTCapsulePartKind.PLUG_IN)) {
  ...
}

CapsulePart part = ...;
if (part.getKind().equals(CapsuleKind.PLUGIN)) { ... }

CapsulePartUtils.isCapsulePart( p );

UMLRTCapsulePart.getInstance( p );

	/** Name of the capsule part stereotype. */
	private static final String UML_REAL_TIME_CAPSULE_PART = "UMLRealTime::CapsulePart";

	/**
	 * Determine whether el is a capsule part.
	 * 
	 * @param el
	 *            - An {@link Element}.
	 * @return True iff el has the {@link CapsulePart} stereotype applied.
	 */
	public static boolean isCapsulePart(Element el) {
		Stereotype s = el.getAppliedStereotype(UML_REAL_TIME_CAPSULE_PART);
		return s != null;
	}

	/**
	 * Get the CapsulePart stereotype for el.
	 * 
	 * @param el
	 *            - An {@link Element}.
	 * @return The {@link CapsulePart} stereotype.
	 */
	public static CapsulePart getCapsulePart(Element el) {
		Stereotype s = el.getAppliedStereotype(UML_REAL_TIME_CAPSULE_PART);
		return s == null ? null : (CapsulePart) el.getStereotypeApplication(s);
	}

import org.eclipse.uml2.uml.Class;
import org.eclipse.uml2.uml.Element;
import org.eclipse.uml2.uml.Model;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

import org.eclipse.papyrusrt.xtumlrt.external.predefined.UMLRTProfileUtil;

public class PassiveClassUtils {

	static boolean isPassiveClass(Element el) {
		return el instanceof Class && !UMLRTProfileUtil.isCapsule(el);
	}
	
	static List<Class> getAllPassiveClasses(Model model) {
		return model.allOwnedElements()
				.stream()
				.filter(element -> isPassiveClass(element))
				.collect(Collectors.toCollection(ArrayList<Class>::new));
	}
}