# NOT A PART OF SEAMONKEY IN ANY WAY

Some new, some old filres copiedfrom Rhino to form start of prototyping
environment for Project Brenda


git-svn-id: svn://10.0.0.236/trunk@27571 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/js/js2/java/PreorderNodeIterator.java

@@ -0,0 +1,58 @@
+/* -*- Mode: java; tab-width: 8 -*-
+ * Copyright © 1997, 1998 Netscape Communications Corporation, All Rights Reserved.
+ */
+
+import java.util.Stack;
+
+/**
+ * This class implements a preorder tree iterator for the Node class.
+ *
+ * @see Node
+ * @author Norris Boyd
+ */
+public class PreorderNodeIterator {
+    public PreorderNodeIterator(Node n) {
+    	start = n;
+    	stack = new Stack();
+    }
+
+    public Node currentNode() {
+        return current;
+    }
+
+    public Node getCurrentParent() {
+    	return currentParent;
+    }
+
+    public Node nextNode() {
+        if (current == null)
+            return current = start;
+    	if (current.first != null) {
+    	    stack.push(current);
+    	    currentParent = current;
+    	    current = current.first;
+    	} else {
+    	    current = current.next;
+    	    boolean isEmpty;
+            for (;;) {
+                isEmpty = stack.isEmpty();
+                if (isEmpty || current != null)
+    		        break;
+                current = (Node) stack.pop();
+                current = current.next;
+    	    }
+    	    currentParent = isEmpty ? null : (Node) stack.peek();
+    	}
+    	return current;
+    }
+
+    public void replaceCurrent(Node newNode) {
+        currentParent.replaceChild(current, newNode);
+        current = newNode;
+    }
+
+    private Node start;
+    private Node current;
+    private Node currentParent;
+    private Stack stack;
+}