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diff --git a/bundles/org.simantics.g2d/src/org/simantics/g2d/canvas/impl/HintReflection.java b/bundles/org.simantics.g2d/src/org/simantics/g2d/canvas/impl/HintReflection.java
new file mode 100644
index 000000000..3edd342b7
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+++ b/bundles/org.simantics.g2d/src/org/simantics/g2d/canvas/impl/HintReflection.java
@@ -0,0 +1,185 @@
+/*******************************************************************************
+ * 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.g2d.canvas.impl;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.simantics.utils.datastructures.hints.IHintListener;
+import org.simantics.utils.datastructures.hints.IHintObservable;
+import org.simantics.utils.datastructures.hints.IHintContext.Key;
+
+/**
+ * @author Toni Kalajainen
+ */
+public class HintReflection {
+
+	private final static HintListenerDefinition[] EMPTY = new HintListenerDefinition[0]; 
+	
+	@Retention(RetentionPolicy.RUNTIME)
+	@Target(ElementType.METHOD)
+	public static @interface HintListener {
+		Class<?> 	Class();
+		String 		Field();		
+	}
+	
+	/**
+	 * Scans an object for reflections of hint listeners  
+	 * <p>
+	 * Example:
+	 * 
+	 *  @HintListener(Class=Hints.class, Field="KEY_CANVAS_TRANSFORM")
+	 *	public void hintChanged(IHintObservable sender, Key key, Object oldValue, Object newValue) {
+	 *     ...
+	 *	}
+	 *	@HintListener(Class=Hints.class, Field="KEY_CANVAS_TRANSFORM")
+	 *	public void hintRemoved(IHintObservable sender, Key key, Object oldValue) { 
+	 *     ...
+	 *  }
+	 * 
+	 * @param obj object to scan
+	 * @return an array of painters and their priorities
+	 */
+    public static HintListenerDefinition[] getDependencies(final Object obj)
+	{
+		Map<Key, HintListenerDefinition> result = new HashMap<Key, HintListenerDefinition>();
+		Class<?> clazz = obj.getClass();
+		_add(obj, clazz, result);
+		//if (result==null) return EMPTY;
+		return result.values().toArray(EMPTY);
+	}
+
+    private static void _add(final Object obj, Class<?> clazz, Map<Key, HintListenerDefinition> result)
+	{
+		try {
+			for (final Method m : clazz.getDeclaredMethods()) {
+				HintListener anno = (HintListener) m
+						.getAnnotation(HintListener.class);
+				if (anno == null)
+					continue;
+
+				Class<?> keyContainerClass = anno.Class();
+				assert (keyContainerClass != null);
+				String fieldName = anno.Field();
+				assert (fieldName != null);
+				Field field;
+				field = keyContainerClass.getField(fieldName);
+				assert (field != null);
+				field.setAccessible(true);
+				Object value = field.get(field != null);
+				assert (value != null);
+				assert (value instanceof Key);
+				Key key = (Key) value;
+
+				Class<?> returnType = m.getReturnType();
+				assert (returnType == void.class);
+				Class<?>[] params = m.getParameterTypes();
+				assert (params.length == 4 || params.length == 3);
+				assert (params[0].equals(IHintObservable.class));
+				assert (params[1].equals(Key.class));
+				assert (params[2].equals(Object.class));
+
+				if (params.length == 4) 
+					assert (params[3].equals(Object.class));
+
+				HintListenerDefinition def = result.get(key);
+				if (def==null) {
+					def = new HintListenerDefinition(key, obj);
+					result.put(key, def);
+				}					
+				
+				m.setAccessible(true);					
+				if (params.length == 4)
+					def.changedHandlerMethod = m;
+				else
+					def.removedHandlerMethod = m;
+			}
+		} catch (SecurityException e) {
+			throw new Error(e);
+		} catch (NoSuchFieldException e) {
+			throw new Error(e);
+		} catch (IllegalAccessException e) {
+			throw new Error(e);
+		}
+		/*
+		for (final Field f : clazz.getDeclaredFields()) {
+			Class c = f.getType();
+			Dependency dep = (Dependency) f.getAnnotation(Dependency.class);
+			Reference ref = (Reference) f.getAnnotation(Reference.class);
+			if (dep==null && ref==null) continue;
+			assert(ICanvasParticipant.class.isAssignableFrom( c ));				
+			assert(!(dep!=null && ref!=null));
+			ReferenceDefinition rd = new ReferenceDefinition();
+			rd.dependency = dep!=null;
+			rd.field = f;
+			rd.requirement = c;
+			f.setAccessible(true);
+			result.add(rd);
+		}
+		*/
+		
+		Class<?> superClass = clazz.getSuperclass();
+		if (superClass!=null)
+			_add(obj, superClass, result);
+	}
+
+	
+	public final static class HintListenerDefinition implements IHintListener {
+		public final Key key;
+		public final Object object;
+		public Method changedHandlerMethod;
+		public Method removedHandlerMethod;
+		
+		public HintListenerDefinition(Key key, Object object) {
+			this.key = key;
+			this.object = object;
+		}
+		
+		@Override
+		public void hintChanged(IHintObservable sender, Key key,
+				Object oldValue, Object newValue) {
+			if (changedHandlerMethod==null) return;
+			try {
+				changedHandlerMethod.invoke(object, sender, key, oldValue, newValue);
+			} catch (IllegalArgumentException e) {
+				throw new Error(e);
+			} catch (IllegalAccessException e) {
+				throw new Error(e);
+			} catch (InvocationTargetException e) {
+				throw new RuntimeException(e);
+			}
+		}
+		@Override
+		public void hintRemoved(IHintObservable sender, Key key, Object oldValue) {
+			if (removedHandlerMethod==null) return;
+			try {
+				removedHandlerMethod.invoke(object, sender, key, oldValue);
+			} catch (IllegalArgumentException e) {
+				throw new Error(e);
+			} catch (IllegalAccessException e) {
+				throw new Error(e);
+			} catch (InvocationTargetException e) {
+				throw new RuntimeException(e.getCause());
+			}
+		}
+		
+		
+	}	
+	
+}