eliminato classi superflue del progetto e risolto qualche bug. c'è ancora del lavoro da fare sulla queue e deque

stack/NodeStack.java

@@ -1,7 +1,6 @@
 package stack;
 
 import exceptions.EmptyStackException;
-import exceptions.FullStackException;
 import stack.utility.Node;
 
 /**
@@ -15,7 +14,7 @@ import stack.utility.Node;
 public class NodeStack<E> implements Stack<E> {
 
     @Override
-    public void push(E element) throws FullStackException {
+    public void push(E element)  {
         Node<E> temp = new Node<E>(element,stack);
         stack = temp;
         ++number_of_elements;
@@ -60,6 +59,24 @@ public class NodeStack<E> implements Stack<E> {
         return number_of_elements;
     }
 
+    @Override
+    public String toString() {
+        String to_return = "";
+        to_return = to_return + "[";
+
+        for (  Node<E> temp = stack; temp != null ; temp = temp.getNext()){
+
+            if ( temp.getNext() == null){
+                to_return+=(temp.getElement().toString());
+            }else{
+                to_return+=( temp.getElement().toString() + ",");
+            }
+        }
+        to_return = to_return + "]";
+
+        return to_return;
+    }
+
 
     private Node<E> stack = null;
     private int number_of_elements = 0;