Implementato Iterator in NodePositionList e aggiunto solo i prototipi nelle altre classe che implementano Sequence

position/NodePositionList.java

@@ -1,6 +1,10 @@
 package position;
 import  exceptions.*;
 import position.utility.DNode;
+import sun.org.mozilla.javascript.internal.ObjToIntMap;
+
+import java.util.Iterator;
+import java.util.NoSuchElementException;
 
 /**
  * Realization of a PositionList using a doubly-linked list of nodes.
@@ -187,4 +191,74 @@ public class NodePositionList<E> implements PositionList<E> {
     }
 
 
+    @Override
+    public Iterator<E> iterator() {
+        return new MyIterator(this);
+    }
+
+    class MyIterator implements Iterator<E>{
+
+        public MyIterator (NodePositionList<E> structure){
+
+             new_structure = new NodePositionList<E>();
+             if (structure.size() != 0){
+                 Position<E> temp;
+                 for (temp = structure.first() ; temp!= structure.last()  ; temp = structure.next(temp)){
+                     new_structure.addLast(temp.element());
+                 }
+                 new_structure.addLast(temp.element());
+             }
+
+        }
+
+        @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 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() {
+
+        }
+
+        NodePositionList<E> new_structure;
+        Position<E> pos = null;
+
+
+    }
+
+
 }

position/PositionList.java

@@ -9,7 +9,7 @@ import  exceptions.*;
 //Copyright (c) 2003 Brown University, Providence, RI
 //Additional modifications and methods by xgiovio
 
-public interface PositionList<E> {
+public interface PositionList<E> extends Iterable<E> {
 
 
   public int size();