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diff --git a/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/cache/WeakCachedProvider.java b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/cache/WeakCachedProvider.java
new file mode 100644
index 000000000..bc611a692
--- /dev/null
+++ b/bundles/org.simantics.utils.datastructures/src/org/simantics/utils/datastructures/cache/WeakCachedProvider.java
@@ -0,0 +1,64 @@
+/*******************************************************************************
+ * 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.cache;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * Caches the value provided by provider until the value has been garbage collected.
+ * <p>
+ * Cached IProvider provides the same instance as long as it is in memory.
+ * <p>
+ * Cached version is equal to original in hashCode/equals wise.
+ * 
+ * @author Toni Kalajainen
+ */
+public class WeakCachedProvider<V> implements IProvider<V> {
+
+    public static final <V> IProvider<V> cache(IProvider<V> provider)
+    {
+        if (provider instanceof WeakCachedProvider<?>)
+            return provider;
+        return new WeakCachedProvider<V>(provider);
+    }
+
+    IProvider<V> provider;
+    WeakReference<V> ref;
+
+    WeakCachedProvider(IProvider<V> orig)
+    {
+        this.provider = orig;
+    }
+
+    @Override
+    public synchronized V get() throws ProvisionException {
+        if (ref!=null) {
+            V x = ref.get();
+            if (x==null) ref=null;
+            else return x;
+        }
+        V x = provider.get();
+        ref = new WeakReference<V>(x);
+        return x;
+    }
+
+    @Override
+    public int hashCode() {
+        return provider.hashCode();
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        return provider.equals(obj);
+    }
+
+}