1 files changed, 92 insertions, 0 deletions
diff --git a/plugins/infra/misc/org.eclipse.papyrus.infra.sync/src/org/eclipse/papyrus/infra/sync/service/CascadeTriggers.java b/plugins/infra/misc/org.eclipse.papyrus.infra.sync/src/org/eclipse/papyrus/infra/sync/service/CascadeTriggers.java
new file mode 100644
index 00000000000..5a9da663c30
--- /dev/null
+++ b/plugins/infra/misc/org.eclipse.papyrus.infra.sync/src/org/eclipse/papyrus/infra/sync/service/CascadeTriggers.java
@@ -0,0 +1,92 @@
+/*****************************************************************************
+ * Copyright (c) 2015 Christian W. Damus 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:
+ *   Christian W. Damus - Initial API and implementation
+ *   
+ *****************************************************************************/
+
+package org.eclipse.papyrus.infra.sync.service;
+
+import org.eclipse.core.runtime.IStatus;
+import org.eclipse.core.runtime.MultiStatus;
+import org.eclipse.core.runtime.Status;
+import org.eclipse.papyrus.infra.sync.Activator;
+import org.eclipse.papyrus.infra.sync.internal.SyncService;
+
+import com.google.common.base.Function;
+
+/**
+ * A sync action that cascades the evaluation of triggers to related objects.
+ */
+public class CascadeTriggers implements ISyncAction {
+
+	private final ISyncService service = SyncService.getCurrent();
+
+	private Function<Object, ? extends Iterable<?>> cascadeFunction;
+
+	public CascadeTriggers() {
+		this(null);
+	}
+
+	/**
+	 * Initializes me with a cascade function.
+	 */
+	public CascadeTriggers(Function<Object, ? extends Iterable<?>> cascadeFunction) {
+		super();
+
+		this.cascadeFunction = cascadeFunction;
+	}
+
+	/**
+	 * Assigns a function that I use to compute the objects to which to cascade the
+	 * evaluation of synchronization triggers.
+	 */
+	public void setCascadeFunction(Function<Object, ? extends Iterable<?>> cascadeFunction) {
+		this.cascadeFunction = cascadeFunction;
+	}
+
+	/**
+	 * Evaluates sync triggers on the objects related to the given triggered {@code object} by my
+	 * {@linkplain #setCascadeFunction(Function) cascade function}.
+	 */
+	@Override
+	public IStatus perform(ISyncService syncService, Object object) {
+		IStatus result = Status.OK_STATUS;
+
+		for (Object next : cascade(object)) {
+			IStatus nextResult = service.evaluateTriggers(next);
+			if ((nextResult != null) && !nextResult.isOK()) {
+				if (result.isOK()) {
+					result = nextResult;
+				} else if (result.isMultiStatus()) {
+					((MultiStatus) result).merge(nextResult);
+				} else {
+					result = new MultiStatus(Activator.PLUGIN_ID, 0, new IStatus[] { result, nextResult }, "Multiple sync trigger cascade problems occurred.", null);
+				}
+			}
+		}
+
+		return result;
+	}
+
+	/**
+	 * Obtains the objects on which to evaluate cascaded sync triggers, based on the given {@code triggered} object.
+	 * 
+	 * @throws IllegalStateException
+	 *             if I have no {@linkplain #setCascadeFunction(Function) cascade function} with which
+	 *             to compute the cascaded triggers
+	 */
+	protected Iterable<?> cascade(Object triggered) {
+		if (cascadeFunction == null) {
+			throw new IllegalStateException("no cascade function"); //$NON-NLS-1$
+		}
+
+		return cascadeFunction.apply(triggered);
+	}
+}