diff --git a/.gitignore b/.gitignore
index a6d056f2..c1955ab8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,4 +4,11 @@ bin/
 target/
 *~
 .*sw?
-\#*
\ No newline at end of file
+\#*
+.idea/
+*.iml
+
+# vscode
+.project
+.settings/
+.classpath
\ No newline at end of file
diff --git a/odfdom/src/main/java/org/odftoolkit/odfdom/pkg/OdfXMLFactory.java b/odfdom/src/main/java/org/odftoolkit/odfdom/pkg/OdfXMLFactory.java
index 50f3b984..23cd3d50 100644
--- a/odfdom/src/main/java/org/odftoolkit/odfdom/pkg/OdfXMLFactory.java
+++ b/odfdom/src/main/java/org/odftoolkit/odfdom/pkg/OdfXMLFactory.java
@@ -52,6 +52,7 @@ public class OdfXMLFactory {
 	private static Map<OdfName, Class> mElementTypes = new HashMap<OdfName, Class>();
 	private static Map<OdfName, Class> mAttributeTypes = new HashMap<OdfName, Class>();
 	private static Map<String, String> mElementRenames = new HashMap<String, String>();
+	private static Set<OdfName> mAlienTypes = new HashSet<OdfName>();
 	//a set for the element which need to load class from incubator package.
 	private static Set<String> mIncubatorElements = new HashSet<String>();
 	private static final String LOCAL_NAME_DELIMITER = "-";
@@ -116,6 +117,10 @@ private static Class getOdfElementClass(OdfName odfName) {
 	}
 
 	private static Class getOdfNodeClass(OdfName odfName, String nodeType, Map<OdfName, Class> classCache, boolean isAttribute) {
+		if (mAlienTypes.contains(odfName)) {
+			return null;
+		}
+
 		Class c = null;
 		String className = "";
 		c = classCache.get(odfName);
@@ -147,8 +152,10 @@ private static Class getOdfNodeClass(OdfName odfName, String nodeType, Map<OdfNa
 					c = Class.forName(className);
 					classCache.put(odfName, c);
 				} catch (ClassNotFoundException ex) {
+					mAlienTypes.add(odfName);
 					// all classes are first tring to load and warning is given later
 				} catch (NoClassDefFoundError dex) {
+					mAlienTypes.add(odfName);
 					Logger.getLogger(OdfXMLFactory.class.getName()).log(Level.INFO, "NoClassDefFoundError: " + className, dex.getMessage());
 				}
 			}
diff --git a/odfdom/src/test/java/org/odftoolkit/odfdom/pkg/AlienPerformanceTest.java b/odfdom/src/test/java/org/odftoolkit/odfdom/pkg/AlienPerformanceTest.java
new file mode 100644
index 00000000..d6f9e4b3
--- /dev/null
+++ b/odfdom/src/test/java/org/odftoolkit/odfdom/pkg/AlienPerformanceTest.java
@@ -0,0 +1,42 @@
+/************************************************************************
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
+ *
+ * Copyright 2008, 2010 Oracle and/or its affiliates. All rights reserved.
+ *
+ * Use is subject to license terms.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0. You can also
+ * obtain a copy of the License at http://odftoolkit.org/docs/license.txt
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ ************************************************************************/
+package org.odftoolkit.odfdom.pkg;
+
+import org.junit.Test;
+import org.odftoolkit.odfdom.doc.OdfDocument;
+import org.odftoolkit.odfdom.utils.ResourceUtilities;
+
+public class AlienPerformanceTest {
+
+    private static final String ALIEN_PERFORMANCE_FILE = "testAlienPerformance.odt";
+
+    @Test
+    public void testAlienPerformance() throws Exception {
+        OdfDocument doc = OdfDocument.loadDocument(ResourceUtilities.getAbsolutePath(ALIEN_PERFORMANCE_FILE));
+        long startTime=System.currentTimeMillis();
+        doc.getContentDom();
+        doc.getTableList();
+        long endTime=System.currentTimeMillis();
+        float excTime = endTime-startTime;
+        System.out.println("Time escape："+ excTime +"ms");
+    }
+}
diff --git a/odfdom/src/test/resources/testAlienPerformance.odt b/odfdom/src/test/resources/testAlienPerformance.odt
new file mode 100644
index 00000000..d809f8d1
Binary files /dev/null and b/odfdom/src/test/resources/testAlienPerformance.odt differ