diff -r 7ad0eec2c334 xml.xam/src/org/netbeans/modules/xml/xam/dom/AbstractDocumentModel.java
--- a/xml.xam/src/org/netbeans/modules/xml/xam/dom/AbstractDocumentModel.java	Mon May 04 22:21:11 2009 +0400
+++ b/xml.xam/src/org/netbeans/modules/xml/xam/dom/AbstractDocumentModel.java	Tue May 12 19:37:28 2009 +0400
@@ -92,7 +92,9 @@ public abstract class AbstractDocumentMo
     }
     
     public abstract T createRootComponent(Element root);
+
+    public abstract void removeRootComponent();
+
     public boolean areSameNodes(Node n1, Node n2) {
         return getAccess().areSameNodes(n1, n2);
     }


diff -r 7ad0eec2c334 xml.xdm/src/org/netbeans/modules/xml/xdm/xam/XDMListener.java
--- a/xml.xdm/src/org/netbeans/modules/xml/xdm/xam/XDMListener.java	Mon May 04 22:21:11 2009 +0400
+++ b/xml.xdm/src/org/netbeans/modules/xml/xdm/xam/XDMListener.java	Tue May 12 19:37:28 2009 +0400
@@ -173,6 +173,7 @@ public class XDMListener implements Prop
             }
             //assert eventNode.getId() == 1;
             if (! isAdded) {
+                model.removeRootComponent();
                 return;
             }
             Component rootComponent = null;


diff -r 7ad0eec2c334 xml.schema.model/src/org/netbeans/modules/xml/schema/model/impl/SchemaModelImpl.java
--- a/xml.schema.model/src/org/netbeans/modules/xml/schema/model/impl/SchemaModelImpl.java	Mon May 04 22:21:11 2009 +0400
+++ b/xml.schema.model/src/org/netbeans/modules/xml/schema/model/impl/SchemaModelImpl.java	Tue May 12 19:37:28 2009 +0400

@@ -129,8 +129,12 @@ public class SchemaModelImpl extends Abs
 
+    public void removeRootComponent() {
+        schema = null;
+    }
+
 

diff -r 7ad0eec2c334 xml.xam/test/unit/src/org/netbeans/modules/xml/xam/TestModel2.java
--- a/xml.xam/test/unit/src/org/netbeans/modules/xml/xam/TestModel2.java	Mon May 04 22:21:11 2009 +0400
+++ b/xml.xam/test/unit/src/org/netbeans/modules/xml/xam/TestModel2.java	Tue May 12 19:37:28 2009 +0400
@@ -129,6 +130,10 @@ public class TestModel2 extends Abstract
+
+    public void removeRootComponent() {
+        testRoot = null;
+    }
     

diff -r 7ad0eec2c334 xml.xdm/test/unit/src/org/netbeans/modules/xml/xam/TestModel.java
--- a/xml.xdm/test/unit/src/org/netbeans/modules/xml/xam/TestModel.java	Mon May 04 22:21:11 2009 +0400
+++ b/xml.xdm/test/unit/src/org/netbeans/modules/xml/xam/TestModel.java	Tue May 12 19:37:28 2009 +0400
@@ -93,6 +94,11 @@ public class TestModel extends AbstractD
     
+    @Override
+    public void removeRootComponent() {
+        testRoot = null;
+    }
+


diff -r 7ad0eec2c334 xml.xam/nbproject/project.properties
--- a/xml.xam/nbproject/project.properties	Mon May 04 22:21:11 2009 +0400
+++ b/xml.xam/nbproject/project.properties	Thu May 14 19:32:19 2009 +0400
@@ -42,4 +42,5 @@ is.autoload=true
 is.autoload=true
 javac.source=1.5
 javadoc.arch=${basedir}/arch.xml
-spec.version.base=1.5.0
+javadoc.apichanges=${basedir}/apichanges.xml
+spec.version.base=1.6.0

diff -r 7ad0eec2c334 xml.xdm/test/unit/src/org/netbeans/modules/xml/xam/AbstractModelTest.java
--- a/xml.xdm/test/unit/src/org/netbeans/modules/xml/xam/AbstractModelTest.java	Mon May 04 22:21:11 2009 +0400
+++ b/xml.xdm/test/unit/src/org/netbeans/modules/xml/xam/AbstractModelTest.java	Thu May 14 19:32:20 2009 +0400
@@ -589,6 +588,19 @@ public class AbstractModelTest extends N
         assertEquals("root is same", root, model.getRootComponent());
     }	
 	
+    public void testRootDeleted() throws Exception {
+        Document doc = Util.getResourceAsDocument("resources/test1.xml");
+        assert doc != null;
+        TestModel2 model = new TestModel2(doc);
+        model.sync();
+
+        Util.setDocumentContentTo(doc, "resources/test1_rootdeleted.xml");
+        model.sync();
+        assertEquals(Model.State.VALID, model.getState());
+        assertNull(model.getRootComponent());
+    }
+
     public void testPrettyPrint() throws Exception {
         defaultSetup();
         assertEquals("testPrettyPrint.ok", State.VALID, model.getState());


diff -r 7ad0eec2c334 xml.xam/apichanges.xml
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xml.xam/apichanges.xml	Thu May 14 19:35:25 2009 +0400
@@ -0,0 +1,148 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Search for CHANGEME in this document when copying and using it: -->
+<!--
+DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+
+Copyright 1997-2009 Sun Microsystems, Inc. All rights reserved.
+
+The contents of this file are subject to the terms of either the GNU
+General Public License Version 2 only ("GPL") or the Common
+Development and Distribution License("CDDL") (collectively, the
+"License"). You may not use this file except in compliance with the
+License. You can obtain a copy of the License at
+http://www.netbeans.org/cddl-gplv2.html
+or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
+specific language governing permissions and limitations under the
+License.  When distributing the software, include this License Header
+Notice in each file and include the License file at
+nbbuild/licenses/CDDL-GPL-2-CP.  Sun designates this
+particular file as subject to the "Classpath" exception as provided
+by Sun in the GPL Version 2 section of the License file that
+accompanied this code. If applicable, add the following below the
+License Header, with the fields enclosed by brackets [] replaced by
+your own identifying information:
+"Portions Copyrighted [year] [name of copyright owner]"
+
+Contributor(s):
+
+The Original Software is NetBeans. The Initial Developer of the Original
+Software is Sun Microsystems, Inc. Portions Copyright 1997-2009 Sun
+Microsystems, Inc. All Rights Reserved.
+
+If you wish your version of this file to be governed by only the CDDL
+or only the GPL Version 2, indicate your decision by adding
+"[Contributor] elects to include this software in this distribution
+under the [CDDL or GPL Version 2] license." If you do not indicate a
+single choice of license, a recipient has the option to distribute
+your version of this file under either the CDDL, the GPL Version 2 or
+to extend the choice of license to its licensees as provided above.
+However, if you add GPL Version 2 code and therefore, elected the GPL
+Version 2 license, then the option applies only if the new code is
+made subject to such option by the copyright holder.
+-->
+<?xml-stylesheet type="text/xml" href="../nbbuild/javadoctools/apichanges.xsl"?>
+<!DOCTYPE apichanges PUBLIC "-//NetBeans//DTD API changes list 1.0//EN" "../nbbuild/javadoctools/apichanges.dtd">
+
+<!--
+
+INFO FOR PEOPLE ADDING CHANGES:
+
+Check the DTD (apichanges.dtd) for details on the syntax. You do not
+need to regenerate the HTML, as this is part of Javadoc generation; just
+change the XML. Rough syntax of a change (several parts optional):
+
+<change>
+    <api name="compiler"/>
+    <summary>Some brief description here, can use <b>XHTML</b></summary>
+    <version major="1" minor="99"/>
+    <date day="13" month="6" year="2001"/>
+    <author login="jrhacker"/>
+    <compatibility addition="yes"/>
+    <description>
+        The main description of the change here.
+        Again can use full <b>XHTML</b> as needed.
+    </description>
+    <class package="org.openide.compiler" name="DoWhatIWantCompiler"/>
+    <issue number="14309"/>
+</change>
+
+Also permitted elements: <package>, <branch>. <version> is API spec
+version, recommended for all new changes. <compatibility> should say
+if things were added/modified/deprecated/etc. and give all information
+related to upgrading old code. List affected top-level classes and
+link to issue numbers if applicable. See the DTD for more details.
+
+Changes need not be in any particular order, they are sorted in various
+ways by the stylesheet anyway.
+
+Dates are assumed to mean "on the trunk". If you *also* make the same
+change on a stabilization branch, use the <branch> tag to indicate this
+and explain why the change was made on a branch in the <description>.
+
+Please only change this file on the trunk! Rather: you can change it
+on branches if you want, but these changes will be ignored; only the
+trunk version of this file is important.
+
+Deprecations do not count as incompatible, assuming that code using the
+deprecated calls continues to see their documented behavior. But do
+specify deprecation="yes" in <compatibility>.
+
+This file is not a replacement for Javadoc: it is intended to list changes,
+not describe the complete current behavior, for which ordinary documentation
+is the proper place.
+
+-->
+
+<apichanges>
+
+    <!-- First, a list of API names you may use: -->
+    <apidefs>
+        <apidef name="org.netbeans.modules.xml.xam">Extansible Abstract Model (XAM)</apidef>
+        <!-- etc. -->
+    </apidefs>
+
+    <!-- ACTUAL CHANGES BEGIN HERE: -->
+    <changes>
+        
+        <change id="model-changes-notification">
+            <api name="org.netbeans.modules.xml.xam"/>
+            <summary>New method to remove model's root component</summary>
+            <version major="1" minor="6"/>
+            <date day="14" month="5" year="2009"/>
+            <author login="supernikita"/>
+            <compatibility binary="incompatible" source="incompatible" addition="yes"/>
+            <description>
+                <p>
+                Two new abstract method is added:
+                {@link org.netbeans.modules.xml.xam.dom.AbstractDocumentModel#removeRootComponent()}
+		It is intended to be called automatically when a user delete corresponding root component from XML sources.
+                </p>
+            </description>
+            <class package="org.netbeans.modules.xml.xam.dom" name="AbstractDocumentModel"/>
+            <issue number="162769"/>
+        </change>
+
+    </changes>
+
+    <!-- Now the surrounding HTML text and document structure: -->
+
+    <htmlcontents>
+<!-- Generated from apichanges.xml -->
+    <head>
+      <title>Change History for the Extansible Abstract Model (XAM)</title>
+      <link rel="stylesheet" href="prose.css" type="text/css"/>
+    </head>
+    <body>
+
+<p class="overviewlink"><a href="@TOP@/overview-summary.html">Overview</a></p>
+
+<h1>Introduction</h1>
+
+<p>This document lists changes made to the <a href="@TOP@/overview-summary.html">Extansible Abstract Model (XAM)</a>.</p>
+      <hr/>
+      <standard-changelists module-code-name="org.netbeans.modules.xml.xam/1"/>
+      <hr/><p>@FOOTER@</p>
+    </body>
+  </htmlcontents>
+
+</apichanges>