Docs: Add JavaDoc

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

@@ -22,13 +22,15 @@ import java.util.Collections;
 import java.util.Set;
 
 /**
- * This is an empty implementation for a check. Can be used as a normal visitor
- * for the city doctor data model
+ *
+ * This class serves as a Parent for non-validating checks that want to use the CheckEngine's Visitor-pattern for the
+ * implementation of utility functions like e.g. collecting the sub-CityObjects in a Feature.
+ *
  * 
  * @author Matthias Betz
  *
  */
-public class AbstractCheck extends Check {
+public abstract class AbstractCheck extends Check {
 
 	@Override
 	public Set<Requirement> appliesToRequirements() {

CityDoctorParent/CityDoctorValidation/src/main/java/de/hft/stuttgart/citydoctor2/checks/util/CityObjectCollector.java

@@ -6,6 +6,9 @@ import de.hft.stuttgart.citydoctor2.datastructure.CityObject;
 import java.util.HashSet;
 import java.util.Set;
 
+/**
+ * This AbstractCheck collects all CityObjects in the substructure of a Feature.
+ */
 public class CityObjectCollector extends AbstractCheck {
 
     private final Set<CityObject> objects = new HashSet<>();