1 files changed, 111 insertions, 0 deletions
diff --git a/plugins/infra/org.eclipse.papyrus.infra.onefile/src/org/eclipse/papyrus/infra/onefile/model/PapyrusModelHelper.java b/plugins/infra/org.eclipse.papyrus.infra.onefile/src/org/eclipse/papyrus/infra/onefile/model/PapyrusModelHelper.java
new file mode 100644
index 00000000000..8bb7e02f83a
--- /dev/null
+++ b/plugins/infra/org.eclipse.papyrus.infra.onefile/src/org/eclipse/papyrus/infra/onefile/model/PapyrusModelHelper.java
@@ -0,0 +1,111 @@
+/*****************************************************************************
+ * Copyright (c) 2011 Atos Origin Integration.
+ *    
+ * 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:
+ *  Tristan Faure (Atos Origin Integration) tristan.faure@atosorigin.com - Initial API and implementation
+ *****************************************************************************/
+package org.eclipse.papyrus.infra.onefile.model;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+
+import org.eclipse.core.runtime.IConfigurationElement;
+import org.eclipse.core.runtime.Platform;
+import org.eclipse.papyrus.infra.onefile.Activator;
+import org.osgi.framework.Bundle;
+
+/**
+ * Helper class able to get the correct {@link IPapyrusModelFactory}
+ * 
+ * @author tfaure
+ * 
+ */
+public class PapyrusModelHelper {
+
+	private static final String MODEL_FACTORY = "modelFactory";
+	static List<Segment> segments;
+
+	static {
+		IConfigurationElement[] elements = Platform
+				.getExtensionRegistry()
+				.getConfigurationElementsFor(Activator.PLUGIN_ID, MODEL_FACTORY);
+		segments = new ArrayList<PapyrusModelHelper.Segment>(elements.length);
+		for (IConfigurationElement e : elements) {
+			Segment s = new PapyrusModelHelper.Segment();
+			try {
+				s.priority = Integer.parseInt(e.getAttribute("priority"));
+				s.bundle = Platform.getBundle(e.getContributor().getName());
+				s.className = e.getAttribute("instance");
+				segments.add(s);
+			} catch (NumberFormatException ex) {
+				// in case of exception the process continue but the stack is
+				// traced
+				ex.printStackTrace();
+			}
+		}
+		// sort elements according to their priorities
+		Collections.sort(segments, new Comparator<Segment>() {
+			public int compare(Segment o1, Segment o2) {
+				Integer val1 = 0;
+				Integer val2 = 0;
+				if (o1 != null) {
+					val1 = o1.priority;
+				}
+				if (o2 != null) {
+					val2 = o2.priority;
+				}
+				return val1.compareTo(val2);
+			}
+		});
+	}
+
+	/**
+	 * get the {@link IPapyrusModelFactory} in the current platform
+	 * 
+	 * @return a {@link IPapyrusModelFactory}
+	 */
+	public static IPapyrusModelFactory getPapyrusModelFactory() {
+		if (segments == null || segments.size() == 0) {
+			throw new RuntimeException(
+					"Initialisation error, please register extension to "
+							+ Activator.PLUGIN_ID + "." + MODEL_FACTORY);
+		}
+		// segments are sorted by priorities, the highest is at the end of the
+		// list
+		return segments.get(segments.size() - 1).getFactory();
+	}
+
+	/**
+	 * Utility class to save extension point information
+	 * 
+	 */
+	private static class Segment {
+		public String className;
+		Bundle bundle;
+		int priority;
+		IPapyrusModelFactory instance = null;
+
+		IPapyrusModelFactory getFactory() {
+			if (instance == null) {
+				try {
+					instance = (IPapyrusModelFactory) bundle.loadClass(
+							className).newInstance();
+				} catch (InstantiationException e) {
+					e.printStackTrace();
+				} catch (IllegalAccessException e) {
+					e.printStackTrace();
+				} catch (ClassNotFoundException e) {
+					e.printStackTrace();
+				}
+			}
+			return instance;
+		}
+	}
+}