fixed an issue with checks that apply to superclasses instead of actual instances

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/check/Check.java

@@ -126,7 +126,7 @@ public abstract class Check {
 	 */
 	public boolean canExecute(Checkable c) {
 		// ignore objects where this check doesn't apply to
-		if (!getApplicableToClasses().contains(c.getCheckClass())) {
+		if (!canBeApplied(c)) {
 			return false;
 		}
 		// check that object doesn't have errors for dependencies of this check
@@ -146,6 +146,15 @@ public abstract class Check {
 		return true;
 	}
 	
+	private boolean canBeApplied(Checkable c) {
+		for (Class<Checkable> checkableClass : getApplicableToClasses()) {
+			if (checkableClass.isAssignableFrom(c.getCheckClass())) {
+				return true;
+			}
+		}
+		return false;
+	}
+
 	/**
 	 * check anything
 	 * 

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/check/Checkable.java

@@ -75,6 +75,11 @@ public abstract class Checkable implements Serializable {
 	 */
 	public abstract GmlId getGmlId();
 	
+	public boolean hasGmlId() {
+		return false;
+	}
+
+
 	/**
 	 * This should be called before executing a check if low memory consumption
 	 * method has been enabled. This should create edges and additional meta

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/datastructure/GmlElement.java

@@ -73,4 +73,9 @@ public abstract class GmlElement extends Checkable {
 		}
 		return gmlId;
 	}
+	
+	@Override
+	public boolean hasGmlId() {
+		return gmlId != null;
+	}
 }