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diff --git a/gnu/java/beans/encoder/Root.java b/gnu/java/beans/encoder/Root.java
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+/* Root.java -- The root of an object tree.
+ Copyright (C) 2005 Free Software Foundation, Inc.
+
+ This file is part of GNU Classpath.
+
+ GNU Classpath is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ GNU Classpath is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GNU Classpath; see the file COPYING.  If not, write to the
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ 02110-1301 USA.
+
+ Linking this library statically or dynamically with other modules is
+ making a combined work based on this library.  Thus, the terms and
+ conditions of the GNU General Public License cover the whole
+ combination.
+
+ As a special exception, the copyright holders of this library give you
+ permission to link this library with independent modules to produce an
+ executable, regardless of the license terms of these independent
+ modules, and to copy and distribute the resulting executable under
+ terms of your choice, provided that you also meet, for each linked
+ independent module, the terms and conditions of the license of that
+ module.  An independent module is a module which is not derived from
+ or based on this library.  If you modify this library, you may extend
+ this exception to your version of the library, but you are not
+ obligated to do so.  If you do not wish to do so, delete this
+ exception statement from your version. */
+
+
+package gnu.java.beans.encoder;
+
+import java.beans.XMLEncoder;
+import java.util.Iterator;
+import java.util.Stack;
+
+import gnu.java.beans.encoder.elements.Element;
+
+/** <p><code>Root</code> provides a simple interface to a tree of
+ * objects.</p>
+ * 
+ * <p>Using an instance of this class a logical representation of
+ * the real object tree that is serialized can be built. When the
+ * actual data should be written as XML <code>Root</code> and
+ * {@link gnu.java.beans.encoder.elements.Element} class can provide
+ * context information which is used to write the best fitting
+ * XML representation.</p>
+ *   
+ * @author Robert Schuster (robertschuster@fsfe.org)
+ */
+public class Root
+{
+  private Stack parents = new Stack();
+
+  private Element rootElement, current;
+  
+  private boolean started;
+
+  public Root()
+  {
+    rootElement = current = new RootElement();
+  }
+
+  /** <p>Adds another child element to the tree.</p>
+   * 
+   * <p>The new element automatically becomes the current
+   * element.</p>
+   * 
+   * @param elem The new child element.
+   */
+  public void addChild(Element elem)
+  {
+    current.addChild(elem);
+
+    parents.push(current);
+    current = elem;
+  }
+
+  /**
+   * <p>Marks that the end of the current element
+   * is reached and that no more childs are added to
+   * it.</p>
+   * 
+   * <p>The behavior is to return to the nearest parent
+   * element.</p>
+   */
+  public void end()
+  {
+    current = (Element) parents.pop();
+  }
+
+  /**
+   * <p>Goes back to the nearest parent element but
+   * deletes the just created child.</p>
+   * 
+   * <p>This is used if something went wrong while
+   * processing the child element's {@link java.beans.Expression}
+   * or {@link java.beans.Statement}.</p>
+   *
+   */
+  public void deleteLast()
+  {
+    current = (Element) parents.pop();
+
+    current.removeLast();
+  }
+
+  /**
+   * <p>Traverses the elements in the object tree
+   * and creates their XML representation in the output
+   * stream of the given {@link Writer}.</p>
+   * 
+   * <p>Finally the <code>Writer</code> is flushed.</p>
+   *  
+   * @param writer The Writer instance that generates the XML representation.
+   */
+  public void traverse(Writer writer)
+  {
+    if (!started)
+      {
+        writer.writePreamble();
+        rootElement.writeStart(writer);
+      }
+    started = true;
+    
+    traverse(writer, rootElement.iterator());
+    
+    rootElement.clear();
+    
+    writer.flush();
+  }
+
+  /** Writes the closing element and closes the {@link Writer}
+   * 
+   * @param writer The Writer instance that generates the XML representation.
+   */
+  public void close(Writer writer)
+  {
+    rootElement.writeEnd(writer);
+    writer.close();
+  }
+
+  /** Recursively traverses the object tree.
+   * 
+   * @param writer The Writer instance that generates the XML representation.
+   * @param ite An Iterator returning Element instances.
+   */
+  private void traverse(Writer writer, Iterator ite)
+  {
+    while (ite.hasNext())
+      {
+        Element e = (Element) ite.next();
+        e.writeStart(writer);
+
+        traverse(writer, e.iterator());
+
+        e.writeEnd(writer);
+        
+        e.clear();
+      }
+  }
+
+  /** <p>A special Element implementation that represents the
+   * encoder's context.</p>
+   * 
+   * <p>This element is written only once per Writer.</p>
+   * 
+   * <p>It is assumed that this element is never empty to simplify
+   * the implementation.</p>
+   * 
+   * @author Robert Schuster (robertschuster@fsfe.org);
+   *
+   */
+  static class RootElement extends Element
+  {
+    public void writeStart(Writer writer)
+    {
+      writer.write("java", new String[] { "version", "class" },
+                   new String[] { System.getProperty("java.version"),
+                                 XMLEncoder.class.getName() }, false);
+    }
+    
+    public void writeEnd(Writer writer)
+    {
+      writer.writeEnd(false);
+    }
+
+  }
+
+}