406647: task data gets corrupted when falling back to XML 1.1

Change-Id: I28a69c4aec071ae5ac72aa007285f9ca2acbedb1
Task-Url: https://bugs.eclipse.org/bugs/show_bug.cgi?id=406647

3 files changed, 54 insertions, 4 deletions

diff --git a/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/TaskRepositoriesExternalizer.java b/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/TaskRepositoriesExternalizer.java
index 6eb633bcc..9f0a33137 100644
--- a/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/TaskRepositoriesExternalizer.java
+++ b/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/TaskRepositoriesExternalizer.java
@@ -29,7 +29,6 @@ import org.eclipse.mylyn.commons.core.StatusHandler;
 import org.eclipse.mylyn.tasks.core.TaskRepository;
 import org.xml.sax.InputSource;
 import org.xml.sax.XMLReader;
-import org.xml.sax.helpers.XMLReaderFactory;
 
 /**
  * @author Rob Elves
@@ -112,7 +111,7 @@ public class TaskRepositoriesExternalizer {
 			}
 
 			SaxRepositoriesContentHandler contentHandler = new SaxRepositoriesContentHandler();
-			XMLReader reader = XMLReaderFactory.createXMLReader();
+			XMLReader reader = XmlReaderUtil.createXmlReader();
 			reader.setContentHandler(contentHandler);
 			reader.parse(new InputSource(inputStream));
 			return contentHandler.getRepositories();
@@ -132,4 +131,5 @@ public class TaskRepositoriesExternalizer {
 			}
 		}
 	}
+
 }
diff --git a/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/XmlReaderUtil.java b/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/XmlReaderUtil.java
new file mode 100644
index 000000000..482d017fc
--- /dev/null
+++ b/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/XmlReaderUtil.java
@@ -0,0 +1,50 @@
+/*******************************************************************************
+ * Copyright (c) 2013 Tasktop Technologies and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Tasktop Technologies - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.mylyn.internal.tasks.core;
+
+import javax.xml.parsers.ParserConfigurationException;
+import javax.xml.parsers.SAXParser;
+import javax.xml.parsers.SAXParserFactory;
+
+import org.xml.sax.SAXException;
+import org.xml.sax.XMLReader;
+
+/**
+ * Utility to create {@link XMLReader} instances. Uses Xerces if available to ensure XML 1.1 parsing works correctly.
+ * 
+ * @author Steffen Pingel
+ */
+public class XmlReaderUtil {
+
+	public static XMLReader createXmlReader() throws SAXException {
+		try {
+			// use Xerces to ensure XML 1.1 is handled correctly
+			Class<?> clazz = Class.forName("org.apache.xerces.parsers.SAXParser"); //$NON-NLS-1$
+			return (XMLReader) clazz.newInstance();
+		} catch (Throwable e) {
+			SAXParser saxParser;
+			try {
+				SAXParserFactory saxParserFactory = SAXParserFactory.newInstance();
+				saxParserFactory.setNamespaceAware(true);
+				saxParser = saxParserFactory.newSAXParser();
+			} catch (ParserConfigurationException e2) {
+				throw new SAXException(e2);
+			}
+			return saxParser.getXMLReader();
+		}
+	}
+
+	private XmlReaderUtil() {
+		// clients must not instantiate class
+	}
+
+}
diff --git a/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/data/TaskDataExternalizer.java b/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/data/TaskDataExternalizer.java
index 02c1d353b..477b467c8 100644
--- a/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/data/TaskDataExternalizer.java
+++ b/org.eclipse.mylyn.tasks.core/src/org/eclipse/mylyn/internal/tasks/core/data/TaskDataExternalizer.java
@@ -27,6 +27,7 @@ import javax.xml.transform.stream.StreamResult;
 
 import org.eclipse.core.runtime.ISafeRunnable;
 import org.eclipse.core.runtime.SafeRunner;
+import org.eclipse.mylyn.internal.tasks.core.XmlReaderUtil;
 import org.eclipse.mylyn.tasks.core.AbstractRepositoryConnector;
 import org.eclipse.mylyn.tasks.core.IRepositoryManager;
 import org.eclipse.mylyn.tasks.core.TaskRepository;
@@ -36,7 +37,6 @@ import org.eclipse.mylyn.tasks.core.data.TaskData;
 import org.xml.sax.InputSource;
 import org.xml.sax.SAXException;
 import org.xml.sax.XMLReader;
-import org.xml.sax.helpers.XMLReaderFactory;
 
 /**
  * @author Steffen Pingel
@@ -177,7 +177,7 @@ public class TaskDataExternalizer {
 	}
 
 	public TaskDataState readState(InputStream in) throws IOException, SAXException {
-		XMLReader parser = XMLReaderFactory.createXMLReader();
+		XMLReader parser = XmlReaderUtil.createXmlReader();
 		TaskDataStateReader handler = new TaskDataStateReader(taskRepositoryManager);
 		parser.setContentHandler(handler);
 		parser.parse(new InputSource(in));