uebung09

uebung09/src/collection/SetFactory.java

@@ -11,8 +11,7 @@ public class SetFactory {
      * @return the empty set.
      */
     static <T> Set<T> create() {
-        // TODO implement
-        return null;
+        return new EmptySet<T>();
     }
 
     /**
@@ -23,8 +22,7 @@ public class SetFactory {
      * @return the singleton set containing the specified element.
      */
     static <T> Set<T> create(T element) {
-        // TODO implement
-        return null;
+        return new SingeltonSet<T>(element);
     }
 
     /**
@@ -35,7 +33,14 @@ public class SetFactory {
      * @return a set containing the specified elements.
      */
     static <T> Set<T> create(T... elems) {
-        // TODO implement
-        return null;
+        if (elems.length == 0) return create();
+        if (elems.length == 1) return create(elems[0]);
+        Set<T> result = create();
+
+        for (T t : elems) {
+            result = result.add(t);
+        }
+
+        return result;
     }
 }