components/visual-panels/core/src/java/util/com/oracle/solaris/vp/util/misc/finder/IconFinder.java
changeset 827 0944d8c0158b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/components/visual-panels/core/src/java/util/com/oracle/solaris/vp/util/misc/finder/IconFinder.java	Thu May 24 04:16:47 2012 -0400
@@ -0,0 +1,137 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright (c) 2009, 2012, Oracle and/or its affiliates. All rights reserved.
+ */
+
+package com.oracle.solaris.vp.util.misc.finder;
+
+import java.net.URL;
+import javax.swing.ImageIcon;
+
+public class IconFinder extends ResourceFinder {
+    //
+    // Instance data
+    //
+
+    private ObjectCache<String, ImageIcon> cache =
+	new ObjectCache<String, ImageIcon>();
+
+    //
+    // IconFinder methods
+    //
+
+    /**
+     * Clear the cache of retrieved {@code ImageIcon}s.
+     */
+    public void clearCache() {
+	synchronized (cache) {
+	    cache.clear();
+	}
+    }
+
+    /**
+     * Return an {@code ImageIcon} for the given resource name.  All packages
+     * in the hierarchy above the given package are searched, using the given
+     * {@code ClassLoader}.  See the class notes for details on the search
+     * algorithm.
+     *
+     * @param	    loader
+     *		    the {@code ClassLoader} to load the resource, or {@code
+     *		    null} to use the system {@code ClassLoader}
+     *
+     * @param	    pkg
+     *		    a point in the package hierarchy to search for the resource
+     *
+     * @param	    name
+     *		    the name of the resource
+     *
+     * @return	    a {@code URL} object, or {@code null} if no resource with
+     *		    this name is found
+     */
+    public ImageIcon getIcon(ClassLoader loader, String pkg, String name) {
+	URL url = getResource(loader, pkg, name);
+	return url == null ? null : getIcon(url);
+    }
+
+    /**
+     * Return an {@code ImageIcon} for the given resource name.  All packages in
+     * the hierarchy above the given package are searched, using the caller's
+     * {@code ClassLoader}.  See the class notes for details on the search
+     * algorithm.
+     *
+     * @param	    pkg
+     *		    a point in the package hierarchy to search for the resource
+     *
+     * @param	    name
+     *		    the name of the resource
+     *
+     * @return	    a {@code URL} object, or {@code null} if no resource with
+     *		    this name is found
+     */
+    public ImageIcon getIcon(String pkg, String name) {
+	URL url = getResource(pkg, name);
+	return url == null ? null : getIcon(url);
+    }
+
+    /**
+     * Return an {@code ImageIcon} for the given resource name.  All packages in
+     * the hierarchy above the calling class are searched, using the caller's
+     * {@code ClassLoader}.  See the class notes for details on the search
+     * algorithm.
+     *
+     * @param	    name
+     *		    the name of the resource
+     *
+     * @return	    a {@code URL} object, or {@code null} if no resource with
+     *		    this name is found
+     */
+    public ImageIcon getIcon(String name) {
+	URL url = getResource(name);
+	return url == null ? null : getIcon(url);
+    }
+
+    //
+    // Private methods
+    //
+
+    /**
+     * Retrieve from cache, or create, an {@code ImageIcon} for the given {@code
+     * URL}.
+     */
+    private ImageIcon getIcon(URL url) {
+	String key = url.toString();
+	ImageIcon icon = null;
+
+	synchronized (cache) {
+	    if (cache.containsKey(key)) {
+		// May be null
+		icon = cache.get(key);
+	    } else {
+		icon = new ImageIcon(url);
+		cache.put(key, icon);
+	    }
+	}
+
+	return icon;
+    }
+}