Commit Paul's MemoryUtils to JME3 util package

git-svn-id: https://jmonkeyengine.googlecode.com/svn/trunk@10426 75d07b2b-3a1a-0410-a2c5-0572b91ccdca

engine/src/core/com/jme3/util/MemoryUtils.java

@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2009-2012 jMonkeyEngine
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
+ *   may be used to endorse or promote products derived from this software
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.jme3.util;
+
+import java.lang.management.ManagementFactory;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import javax.management.JMException;
+import javax.management.MBeanServer;
+import javax.management.MalformedObjectNameException;
+import javax.management.ObjectName;
+
+/**
+ * See thread http://jmonkeyengine.org/forum/topic/monitor-direct-memory-usage-in-your-app/#post-205999
+ * @author Paul Speed
+ */
+public class MemoryUtils {
+    private static MBeanServer mbeans = ManagementFactory.getPlatformMBeanServer();
+    private static ObjectName directPool;
+    static {
+        try {
+            // Create the name reference for the direct buffer pool’s MBean
+            directPool = new ObjectName("java.nio:type=BufferPool,name=direct");
+        } catch (MalformedObjectNameException ex) {
+            Logger.getLogger(MemoryUtils.class.getName()).log(Level.SEVERE, "Error creating direct pool ObjectName", ex);
+        }
+    }
+
+    /**
+     * 
+     * @return the direct memory used in byte.
+     */
+    public static long getDirectMemoryUsage() {
+        try {
+            Long value = (Long)mbeans.getAttribute(directPool, "MemoryUsed");
+            return value == null ? -1 : value;
+        } catch (JMException ex) {
+            Logger.getLogger(MemoryUtils.class.getName()).log(Level.SEVERE, "Error retrieving ‘MemoryUsed’", ex);
+            return -1;
+        }
+    }
+
+    /**
+     * 
+     * @return the number of direct buffer used
+     */
+    public static long getDirectMemoryCount() {
+        try {
+            Long value = (Long)mbeans.getAttribute(directPool, "Count");
+            return value == null ? -1 : value;
+        } catch (JMException ex) {
+            Logger.getLogger(MemoryUtils.class.getName()).log(Level.SEVERE, "Error retrieving ‘Count’", ex);
+            return -1;
+        }
+    }
+
+    /**
+     * 
+     * @return Should return the total direct memory available, result seem off
+     * see post http://jmonkeyengine.org/forum/topic/monitor-direct-memory-usage-in-your-app/#post-205999
+     */
+    public static long getDirectMemoryTotalCapacity() {
+        try {
+            Long value = (Long)mbeans.getAttribute(directPool, "TotalCapacity");
+            return value == null ? -1 : value;
+        } catch (JMException ex) {
+            Logger.getLogger(MemoryUtils.class.getName()).log(Level.SEVERE, "Error retrieving ‘TotalCapacity’", ex);
+            return -1;
+        }
+    }
+}