1 files changed, 164 insertions, 0 deletions
diff --git a/plugins/infra/nattable/org.eclipse.papyrus.infra.nattable.common/src/org/eclipse/papyrus/infra/nattable/common/reconciler/TableReconcilersReader.java b/plugins/infra/nattable/org.eclipse.papyrus.infra.nattable.common/src/org/eclipse/papyrus/infra/nattable/common/reconciler/TableReconcilersReader.java
new file mode 100644
index 00000000000..6b5fcb1eef7
--- /dev/null
+++ b/plugins/infra/nattable/org.eclipse.papyrus.infra.nattable.common/src/org/eclipse/papyrus/infra/nattable/common/reconciler/TableReconcilersReader.java
@@ -0,0 +1,164 @@
+/*****************************************************************************
+ * Copyright (c) 2017 CEA LIST.
+ *
+ * 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:
+ *
+ *		Maged Elaasar - Initial API and implementation
+ *
+ *****************************************************************************/
+package org.eclipse.papyrus.infra.nattable.common.reconciler;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.IConfigurationElement;
+import org.eclipse.core.runtime.Platform;
+import org.eclipse.emf.ecore.plugin.RegistryReader;
+import org.eclipse.papyrus.infra.nattable.common.Activator;
+
+/**
+ * A reader of table reconcilers from the extensions
+ */
+public class TableReconcilersReader extends RegistryReader {
+
+	private static volatile TableReconcilersReader ourInstance = null;
+
+	private static final String EXT_PT = "tableReconciler"; //$NON-NLS-1$
+
+	private static final String TAG_TABLE_RECONCILER = "tableReconciler"; //$NON-NLS-1$
+
+	private List<TableReconciler> myReconcilers;
+
+	public final static TableReconcilersReader getInstance() {
+		if (ourInstance == null) {
+			synchronized (TableReconcilersReader.class) {
+				if (ourInstance == null) {
+					ourInstance = new TableReconcilersReader();
+				}
+			}
+		}
+		return ourInstance;
+	}
+
+	TableReconcilersReader() {
+		super(Platform.getExtensionRegistry(), Activator.PLUGIN_ID, EXT_PT);
+	}
+
+	/**
+	 * @return unmodifiable map of loaded reconcilers
+	 */
+	public synchronized List<TableReconciler> load() {
+		if (myReconcilers == null) {
+			myReconcilers = new ArrayList<TableReconciler>();
+			readRegistry();
+		}
+		return myReconcilers;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 *
+	 * @see org.eclipse.emf.ecore.plugin.RegistryReader#readElement(org.eclipse.core.runtime.IConfigurationElement, boolean)
+	 */
+	@Override
+	protected boolean readElement(IConfigurationElement element, boolean add) {
+		if (!TAG_TABLE_RECONCILER.equals(element.getName())) {
+			return false;
+		}
+
+		String className = element.getAttribute(TableReconciler.ATTR_RECONCILER_CLASS);
+		String sourceVersion = element.getAttribute(TableReconciler.ATTR_SOURCE_VERSION);
+		String targetVersion = element.getAttribute(TableReconciler.ATTR_TARGET_VERSION);
+
+		if (!checkNotEmpty(className)) {
+			logMissingAttribute(element, TableReconciler.ATTR_RECONCILER_CLASS);
+			return false;
+		}
+		if (!checkNotEmpty(sourceVersion)) {
+			logMissingAttribute(element, TableReconciler.ATTR_SOURCE_VERSION);
+			return false;
+		}
+
+		if (!checkNotEmpty(targetVersion)) {
+			logMissingAttribute(element, TableReconciler.ATTR_TARGET_VERSION);
+			return false;
+		}
+		if (!TableVersioningUtils.isCurrentPapyrusVersion(targetVersion)) {
+			Activator.log.debug("Reconciler for outdated version is still registered but will never be executed: " + className); //$NON-NLS-1$
+			return false;
+		}
+
+
+		if (add) {
+			addTableReconciler(element);
+		} else {
+			removeTableReconciler(element);
+		}
+
+		return true;
+	}
+
+	private static boolean checkNotEmpty(String attr) {
+		return (attr != null) && (attr.length() != 0);
+	}
+
+	protected void addTableReconciler(IConfigurationElement element) {
+		TableReconciler reconciler = createReconciler(element);
+		if (reconciler != null) {
+			synchronized (myReconcilers) {
+				myReconcilers.add(reconciler);
+			}
+		}
+	}
+
+	/**
+	 * Unregisters reconciler defined by given extension element.
+	 * <p/>
+	 * Only table type and fully qualified class name will be used to find the one instance to remove.
+	 */
+	protected void removeTableReconciler(IConfigurationElement element) {
+		String fqn = element.getAttribute(TableReconciler.ATTR_RECONCILER_CLASS);
+		if (fqn == null) {
+			// we already have skipped this config at the time of addition
+			return;
+		}
+
+		synchronized (myReconcilers) {
+			for (Iterator<TableReconciler> it = myReconcilers.iterator(); it.hasNext();) {
+				TableReconciler next = it.next();
+				if (fqn.equals(next.getClassFqn())) {
+					it.remove();
+					break;
+				}
+			}
+		}
+	}
+
+	/**
+	 * Instantiates the reconciler defined by given extension
+	 *
+	 * @param element
+	 * @return configured reconciler instance or <code>null</code> if something bad happens (error is logged in this case)
+	 */
+	private TableReconciler createReconciler(IConfigurationElement element) {
+		try {
+			Object reconcilerObject = element.createExecutableExtension(TableReconciler.ATTR_RECONCILER_CLASS);
+			if (reconcilerObject instanceof TableReconciler) {
+				return (TableReconciler) reconcilerObject;
+			} else {
+				Activator.log.error("Table reconciler extension does not extend mandatory TableReconciler base class: " + element.getAttribute(TableReconciler.ATTR_RECONCILER_CLASS), null); //$NON-NLS-1$
+			}
+		} catch (CoreException e) {
+			Activator.log.error(e);
+		}
+		return null;
+	}
+
+}