/*
 * Copyright (C) 2011 the original author or authors.
 * See the notice.md file distributed with this work for additional
 * information regarding copyright ownership.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.iq80.leveldb.util;

import com.google.common.base.Throwables;
import sun.nio.ch.FileChannelImpl;

import java.lang.reflect.Method;
import java.nio.MappedByteBuffer;

public final class ByteBufferSupport
{
    private static final Method unmap;

    static {
        Method x;
        try {
            x = FileChannelImpl.class.getDeclaredMethod("unmap", MappedByteBuffer.class);
        }
        catch (NoSuchMethodException e) {
            throw new AssertionError(e);
        }
        x.setAccessible(true);
        unmap = x;
    }

    private ByteBufferSupport()
    {
    }

    public static void unmap(MappedByteBuffer buffer)
    {
        try {
            unmap.invoke(null, buffer);
        }
        catch (Exception ignored) {
            throw Throwables.propagate(ignored);
        }
    }
}

@@ -803,43 +803,8 @@
 les;
-%0Aimport sun.nio.ch.FileChannelImpl;
 %0A%0Aim
@@ -944,118 +944,529 @@
 hod 
-unmap;%0A%0A    static %7B%0A        Method x;%0A        try %7B%0A            x = FileChannelImpl.class.getDeclared
+getCleaner;%0A    private static final Method clean;%0A%0A    static %7B%0A        try %7B%0A            getCleaner = Class.forName(%22java.nio.DirectByteBuffer%22).getDeclaredMethod(%22cleaner%22);%0A            getCleaner.setAccessible(true);%0A        %7D%0A        catch (ReflectiveOperationException e) %7B%0A            throw new AssertionError(e);%0A        %7D%0A%0A        try %7B%0A            Class%3C?%3E returnType = getCleaner.getReturnType();%0A            if (Runnable.class.isAssignableFrom(returnType)) %7B%0A                clean = Runnable.class.get
 Method(%22
 unma
@@ -1465,40 +1465,116 @@
 od(%22
+r
 un
-map%22, MappedByteBuffer.class);
+%22);%0A            %7D%0A            else %7B%0A                clean = returnType.getMethod(%22clean%22);%0A            %7D
 %0A   
@@ -1677,58 +1677,8 @@
   %7D%0A
-        x.setAccessible(true);%0A        unmap = x;%0A
     
@@ -1815,31 +1815,82 @@
     
-unmap.invoke(null, buff
+Object cleaner = getCleaner.invoke(buffer);%0A            clean.invoke(clean
 er);

Fix unmapping of mmapped files in Java 9