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diff --git a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/HintTracker.java b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/HintTracker.java
new file mode 100644
index 000000000..79f1ce6fc
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+++ b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/hints/HintTracker.java
@@ -0,0 +1,103 @@
+/*******************************************************************************
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management
+ * in Industry THTH ry.
+ * 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:
+ *     VTT Technical Research Centre of Finland - initial API and implementation
+ *******************************************************************************/
+package org.simantics.utils.datastructures.hints;
+
+/**
+ * HintTracker is a helper class for tracking any hints of a single
+ * IHintContext.
+ * 
+ * <p>
+ * The main purpose of this class is to enable very easy switching of the
+ * tracked hint context. Only a call to the {@link #track(IHintContext)} method
+ * is required. All hint listeners registered into the tracked will
+ * automatically be switched to listen to the new context instead.
+ * </p>
+ * 
+ * <p>
+ * The tracker is implemented using HintStack but the
+ * {@link #addHintContext(IHintContext, int)} and
+ * {@link #removeHintContext(IHintContext)} methods are disabled by throwing
+ * {@link UnsupportedOperationException} in both. This is to prevent invalid use
+ * of the class as it is only meant for tracking a single context and nothing
+ * more. Otherwise this class functions exactly like {@link IHintStack} and
+ * {@link IHintObservable} are specified to work.
+ * </p>
+ * 
+ * <p>
+ * The implementation is thread-safe.
+ * </p>
+ * 
+ * <p>
+ * Always be sure to {@link #untrack()} any IHintContext that you're tracking
+ * after the tracker is no longer needed. Otherwise you will most likely have
+ * invalid listeners within the tracked IHintContext resulting in erroneous
+ * behavior.
+ * </p>
+ * 
+ * @author Tuukka Lehtonen
+ */
+public class HintTracker extends HintStack implements IHintTracker {
+    
+    private IHintContext ctx;
+
+    public HintTracker() {
+    }
+
+    public HintTracker(IHintContext ctx) {
+        addHintContext(ctx, 0);
+    }
+
+    /* (non-Javadoc)
+     * @see org.simantics.utils.datastructures.hints.IHintTracker#track(org.simantics.utils.datastructures.hints.IHintContext)
+     */
+    public synchronized final void track(IHintContext ctx) {
+        IHintContext prevCtx = this.ctx;
+        if (ctx == prevCtx)
+            return;
+        this.ctx = ctx;
+
+        if (ctx != null) {
+            if (ctx.equals(prevCtx)) {
+                // remove+add order is necessary in this case.
+                // add+remove would fail since the hint context would
+                // already be found in the hint stack.
+                super.removeHintContext(prevCtx);
+                super.addHintContext(ctx, 0);
+            } else {
+                super.addHintContext(ctx, 0);
+                if (prevCtx != null)
+                    super.removeHintContext(prevCtx);
+            }
+        } else {
+            if (prevCtx != null)
+                super.removeHintContext(prevCtx);
+        }
+    }
+    
+    /* (non-Javadoc)
+     * @see org.simantics.utils.datastructures.hints.IHintTracker#untrack()
+     */
+    public final void untrack() {
+        track(null);
+    }
+    
+    @Override
+    public final void addHintContext(IHintContext hints, int priority) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public final boolean removeHintContext(IHintContext hints) {
+        throw new UnsupportedOperationException();
+    }
+
+}
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