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diff --git a/src/java/com/jogamp/common/util/UnsafeUtil.java b/src/java/com/jogamp/common/util/UnsafeUtil.java
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+++ b/src/java/com/jogamp/common/util/UnsafeUtil.java
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+/**
+ * Copyright 2019 JogAmp Community. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are
+ * permitted provided that the following conditions are met:
+ *
+ *    1. Redistributions of source code must retain the above copyright notice, this list of
+ *       conditions and the following disclaimer.
+ *
+ *    2. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``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 JogAmp Community 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.
+ *
+ * The views and conclusions contained in the software and documentation are those of the
+ * authors and should not be interpreted as representing official policies, either expressed
+ * or implied, of JogAmp Community.
+ */
+package com.jogamp.common.util;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.nio.ByteBuffer;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+
+import com.jogamp.common.ExceptionUtils;
+
+import jogamp.common.Debug;
+import jogamp.common.os.PlatformPropsImpl;
+
+/**
+ * Utility methods allowing easy access to certain {@link sun.misc.Unsafe} functionality.
+ */
+public class UnsafeUtil {
+
+    static final boolean DEBUG;
+    static {
+        DEBUG = Debug.debug("UnsafeUtil");
+    }
+
+    protected UnsafeUtil() {}
+
+    private static final Object theUnsafe;
+    private static final Method unsafeCleanBB;
+    private static volatile boolean hasUnsafeCleanBBError; /** OK to be lazy on thread synchronization, just for early out **/
+
+    private static final Method staticFieldOffset;
+    private static final Method getObjectVolatile;
+    private static final Method putObjectVolatile;
+    private static volatile boolean hasGetPutObjectVolatile;
+
+    private static final Class<?> illegalAccessLoggerClass;
+    private static final Long illegalAccessLoggerOffset;
+    private static final Object illegalAccessLoggerSync = new Object();
+    private static volatile boolean hasIllegalAccessError;
+
+    static {
+        final Object[] _theUnsafe = { null };
+        final Method[] _cleanBB = { null };
+        final Method[] _staticFieldOffset = { null };
+        final Method[] _objectVolatile = { null, null }; // unsafeGetObjectVolatile, unsafePutObjectVolatile
+        final Class<?>[] _illegalAccessLoggerClass = { null };
+        final Long[] _loggerOffset = { null };
+
+        AccessController.doPrivileged(new PrivilegedAction<Object>() {
+            @Override
+            public Object run() {
+                Class<?> unsafeClass = null;
+                try {
+                    // Using: sun.misc.Unsafe { public void invokeCleaner(java.nio.ByteBuffer directBuffer); }
+                    unsafeClass = Class.forName("sun.misc.Unsafe");
+                    {
+                        final Field f = unsafeClass.getDeclaredField("theUnsafe");
+                        f.setAccessible(true);
+                        _theUnsafe[0] = f.get(null);
+                    }
+                    _cleanBB[0] = unsafeClass.getMethod("invokeCleaner", java.nio.ByteBuffer.class);
+                    _cleanBB[0].setAccessible(true);
+                } catch(final Throwable t) {
+                    if( DEBUG ) {
+                        ExceptionUtils.dumpThrowable("UnsafeUtil", t);
+                    }
+                }
+                if( null != _theUnsafe[0] && PlatformPropsImpl.JAVA_9 ) {
+                    try {
+                        _staticFieldOffset[0] = unsafeClass.getDeclaredMethod("staticFieldOffset", Field.class);
+                        _objectVolatile[0] = unsafeClass.getDeclaredMethod("getObjectVolatile", Object.class, long.class);
+                        _objectVolatile[1] = unsafeClass.getDeclaredMethod("putObjectVolatile", Object.class, long.class, Object.class);
+
+                        if( PlatformPropsImpl.JAVA_9 ) {
+                            _illegalAccessLoggerClass[0] = Class.forName("jdk.internal.module.IllegalAccessLogger");
+                            final Field loggerField = _illegalAccessLoggerClass[0].getDeclaredField("logger");
+                            _loggerOffset[0] = (Long) _staticFieldOffset[0].invoke(_theUnsafe[0], loggerField);
+                        }
+                    } catch(final Throwable t) {
+                        if( DEBUG ) {
+                            ExceptionUtils.dumpThrowable("UnsafeUtil", t);
+                        }
+                    }
+                }
+                return null;
+            } } );
+        theUnsafe = _theUnsafe[0];
+        unsafeCleanBB = _cleanBB[0];
+        hasUnsafeCleanBBError = null == theUnsafe || null == unsafeCleanBB;
+        if( DEBUG ) {
+            System.err.println("UnsafeUtil.init: hasTheUnsafe: "+(null!=theUnsafe)+", hasInvokeCleaner: "+!hasUnsafeCleanBBError);
+        }
+
+        staticFieldOffset = _staticFieldOffset[0];
+        getObjectVolatile = _objectVolatile[0];
+        putObjectVolatile = _objectVolatile[1];
+        hasGetPutObjectVolatile = null != staticFieldOffset && null != getObjectVolatile && null != putObjectVolatile;
+        illegalAccessLoggerClass = _illegalAccessLoggerClass[0];
+        illegalAccessLoggerOffset = _loggerOffset[0];
+        hasIllegalAccessError = !hasGetPutObjectVolatile || null == illegalAccessLoggerClass || null == illegalAccessLoggerOffset;
+        if( DEBUG ) {
+            System.err.println("UnsafeUtil.init: hasUnsafeGetPutObjectVolatile: "+hasGetPutObjectVolatile+", hasUnsafeIllegalAccessLogger: "+!hasIllegalAccessError);
+        }
+    }
+
+    /**
+     * Returns {@code true} if {@code sun.misc.Unsafe.invokeCleaner(java.nio.ByteBuffer)}
+     * is available and has not caused an exception.
+     * @see #invokeCleaner(ByteBuffer)
+     */
+    public static boolean hasInvokeCleaner() { return !hasUnsafeCleanBBError; }
+
+    /**
+     * Access to {@code sun.misc.Unsafe.invokeCleaner(java.nio.ByteBuffer)}.
+     * <p>
+     * If {@code b} is an direct NIO buffer, i.e {@link sun.nio.ch.DirectBuffer},
+     * calls it's {@link sun.misc.Cleaner} instance {@code clean()} method once.
+     * </p>
+     * @return {@code true} if successful, otherwise {@code false}.
+     * @see #hasInvokeCleaner()
+     */
+    public static boolean invokeCleaner(final ByteBuffer bb) {
+        if( hasUnsafeCleanBBError || !bb.isDirect() ) {
+            return false;
+        }
+        try {
+            unsafeCleanBB.invoke(theUnsafe, bb);
+            return true;
+        } catch(final Throwable t) {
+            hasUnsafeCleanBBError = true;
+            if( DEBUG ) {
+                ExceptionUtils.dumpThrowable("UnsafeUtil", t);
+            }
+            return false;
+        }
+    }
+
+    /**
+     * Returns {@code true} if access to {@code jdk.internal.module.IllegalAcessLogger}'s {@code logger} field
+     * is available and has not caused an exception.
+     * @see #doWithoutIllegalAccessLogger(PrivilegedAction)
+     */
+    public static boolean hasIllegalAccessLoggerAccess() { return !hasIllegalAccessError; }
+
+    /**
+     * Issue the given user {@code action} while {@code jdk.internal.module.IllegalAcessLogger}'s {@code logger} has been temporarily disabled.
+     * <p>
+     * The caller shall place this call into their own {@link AccessController#doPrivileged(PrivilegedAction)} block.
+     * </p>
+     * <p>
+     * In case the runtime is not {@link PlatformPropsImpl#JAVA_9} or the logger is not accessible or disabling caused an exception,
+     * the user {@code action} is just executed w/o temporary logger modifications.
+     * </p>
+     * @param action the user action task
+     * @throws RuntimeException is thrown for a caught {@link Throwable} while executing the user {@code action}
+     * @see #hasIllegalAccessLoggerAccess()
+     */
+    public static <T> T doWithoutIllegalAccessLogger(final PrivilegedAction<T> action) throws RuntimeException {
+        if( !hasIllegalAccessError ) {
+            synchronized(illegalAccessLoggerSync) {
+                final Object newLogger = null;
+                Object oldLogger = null;
+                try {
+                    oldLogger = getObjectVolatile.invoke(theUnsafe, illegalAccessLoggerClass, illegalAccessLoggerOffset);
+                    putObjectVolatile.invoke(theUnsafe, illegalAccessLoggerClass, illegalAccessLoggerOffset, newLogger);
+                } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+                    // unaccessible ..
+                    hasIllegalAccessError = true;
+                    if( DEBUG ) {
+                        ExceptionUtils.dumpThrowable("UnsafeUtil", e);
+                    }
+                    return action.run();
+                }
+                try {
+                    return action.run();
+                } catch (final Throwable t) {
+                    if( DEBUG ) {
+                        t.printStackTrace();
+                    }
+                    throw new RuntimeException(t);
+                } finally {
+                    try {
+                        putObjectVolatile.invoke(theUnsafe, illegalAccessLoggerClass, illegalAccessLoggerOffset, oldLogger);
+                    } catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
+                        // should not happen, worked above @ logger setup
+                        hasIllegalAccessError = true;
+                        throw new InternalError(e);
+                    }
+                }
+            }
+        } else {
+            return action.run();
+        }
+    }
+}