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diff --git a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/cache/CachedMapProvider.java b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/cache/CachedMapProvider.java
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index 000000000..aefc753e1
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+++ b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/cache/CachedMapProvider.java
@@ -0,0 +1,116 @@
+/*******************************************************************************
+ * 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
+ *******************************************************************************/
+/*
+ *
+ * @author Toni Kalajainen
+ */
+package org.simantics.utils.datastructures.cache;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+
+import org.simantics.utils.datastructures.disposable.AbstractDisposable;
+
+/**
+ * CachedProvider provides values and stores the results in a cache.
+ * Cached values must be explicitly released with clear, retain or remove.
+ * Values are held with strong references.
+ *
+ * @param <K> the key
+ * @param <V> the value
+ */
+public class CachedMapProvider<K, V> extends AbstractDisposable implements IMapProvider<K, V> {
+
+	private Map<K, V> cache;
+	
+	private final IMapProvider<K, V> provider;
+	
+	/**
+	 * Constructs new strong cache
+	 * 
+	 * @param provider provider of values
+	 */
+	public CachedMapProvider(IMapProvider<K, V> provider)
+	{
+		assert(provider!=null);
+		this.provider = provider;
+		this.cache = new HashMap<K, V>();
+	}		
+
+	/**
+	 * Constructs new strong cache
+	 * 
+	 * @param provider provider of values
+	 * @param cacheMap the map to use
+	 */
+	public CachedMapProvider(IMapProvider<K, V> provider, Map<K, V> cacheMap)
+	{
+		assert(provider!=null);
+		this.provider = provider;
+		this.cache = cacheMap;
+	}		
+	
+	@Override
+	public synchronized V get(K key) {
+		assertNotDisposed();
+		V value = cache.get(key);
+		if (value!=null) return value;
+		value = provider.get(key);
+		assert(value!=null);
+		cache.put(key, value);			
+		return value;
+	}
+	
+	public synchronized void clear()
+	{
+		cache.clear();
+	}
+	
+	public synchronized void retain(Set<K> keys)
+	{
+		cache.keySet().retainAll(keys);
+	}
+
+	public synchronized void remove(Set<K> keys)
+	{
+		cache.keySet().removeAll(keys);
+	}
+	
+	public synchronized void load(Set<K> keys)
+	{
+		for (K key : keys)
+			get(key);
+	}
+	
+	public synchronized void addAll(CachedMapProvider<K, V> anotherCache)
+	{
+		assertNotDisposed();
+		cache.putAll(anotherCache.cache);
+	}	
+	
+	public IMapProvider<K, V> getProvider() {
+		return provider;
+	}
+	
+	public synchronized Map<K, V> getAll()
+	{
+		assertNotDisposed();
+		return new HashMap<K, V>(cache);
+	}
+
+	@Override
+	protected void doDispose() {
+		clear();
+	}
+	
+}