Rimosso ArraySequenceFake. Implementato positions() in NodePositionList. Creato il DefaultComparator. Prima implementazione di SortedPriorityList

position/NodePositionList.java

@@ -251,7 +251,7 @@ public class NodePositionList<E> implements PositionList<E> {
 
         @Override
         public void remove() {
-
+            throw new UnsupportedOperationException ();
         }
 
         NodePositionList<E> new_structure;
@@ -260,5 +260,73 @@ public class NodePositionList<E> implements PositionList<E> {
 
     }
 
+    @Override
+    public Iterator<Position<E>> positions() {
+        return new MyPositionsIterator(this);
+    }
 
+    class MyPositionsIterator implements Iterator<Position<E>>{
+
+        public MyPositionsIterator (NodePositionList<E> structure){
+
+            new_structure = new NodePositionList<Position<E>>();
+            if (structure.size() != 0){
+                Position<E> temp;
+                for (temp = structure.first() ; temp!= structure.last()  ; temp = structure.next(temp)){
+                    new_structure.addLast(temp);
+                }
+                new_structure.addLast(temp);
+            }
+
+        }
+
+        @Override
+        public boolean hasNext() {
+            if (pos == null){
+                if (new_structure.size() <= 0){
+                    return false;
+                } else {
+                    return true;
+                }
+
+            } else {
+
+                try {
+                    new_structure.next(pos);
+                    return true;
+                }
+                catch (BoundaryViolationException err){
+                    return false;
+
+                }
+
+
+            }
+        }
+
+        @Override
+        public Position<E> next() throws NoSuchElementException {
+            if (hasNext()){
+                if (pos == null){
+                    pos = new_structure.first();
+                }else {
+                    pos = new_structure.next(pos);
+                }
+                return pos.element();
+            } else{
+                throw new NoSuchElementException();
+            }
+        }
+
+        @Override
+        public void remove() {
+            throw new UnsupportedOperationException ();
+
+        }
+
+        NodePositionList<Position<E>> new_structure;
+        Position<Position<E>> pos = null;
+
+
+    }
 }

position/PositionList.java

@@ -37,5 +37,8 @@ public interface PositionList<E> extends Iterable<E> {
   public E set(Position<E> p, E e) throws InvalidPositionException;
 
 
+  public Iterator<Position<E>> positions();
+
+
 }