1 files changed, 47 insertions, 0 deletions
diff --git a/server/src/org/jsoup/select/NodeTraversor.java b/server/src/org/jsoup/select/NodeTraversor.java
new file mode 100644
index 0000000000..9bb081e56c
--- /dev/null
+++ b/server/src/org/jsoup/select/NodeTraversor.java
@@ -0,0 +1,47 @@
+package org.jsoup.select;
+
+import org.jsoup.nodes.Node;
+
+/**
+ * Depth-first node traversor. Use to iterate through all nodes under and including the specified root node.
+ * <p/>
+ * This implementation does not use recursion, so a deep DOM does not risk blowing the stack.
+ */
+public class NodeTraversor {
+    private NodeVisitor visitor;
+
+    /**
+     * Create a new traversor.
+     * @param visitor a class implementing the {@link NodeVisitor} interface, to be called when visiting each node.
+     */
+    public NodeTraversor(NodeVisitor visitor) {
+        this.visitor = visitor;
+    }
+
+    /**
+     * Start a depth-first traverse of the root and all of its descendants.
+     * @param root the root node point to traverse.
+     */
+    public void traverse(Node root) {
+        Node node = root;
+        int depth = 0;
+        
+        while (node != null) {
+            visitor.head(node, depth);
+            if (node.childNodes().size() > 0) {
+                node = node.childNode(0);
+                depth++;
+            } else {
+                while (node.nextSibling() == null && depth > 0) {
+                    visitor.tail(node, depth);
+                    node = node.parent();
+                    depth--;
+                }
+                visitor.tail(node, depth);
+                if (node == root)
+                    break;
+                node = node.nextSibling();
+            }
+        }
+    }
+}