--- /dev/null
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ * VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.g2d.image.impl;\r
+\r
+import java.lang.ref.WeakReference;\r
+\r
+import org.simantics.g2d.image.Image;\r
+import org.simantics.utils.datastructures.cache.IProvider;\r
+import org.simantics.utils.datastructures.cache.ProvisionException;\r
+\r
+public class CacheProvider extends AbstractProviderProxy {\r
+\r
+ WeakReference<Image> ref;\r
+\r
+ public CacheProvider(IProvider<Image> source) {\r
+ super(source);\r
+ }\r
+\r
+ @Override\r
+ public synchronized Image get() throws ProvisionException {\r
+ if (ref!=null) {\r
+ Image x = ref.get();\r
+ if (x==null) ref=null; else return x;\r
+ }\r
+ Image x = source.get();\r
+ ref = new WeakReference<Image>(x);\r
+ return x; \r
+ }\r
+\r
+ \r
+ \r
+}\r
+\r