| /* |
| * Copyright 2000-2013 JetBrains s.r.o. |
| * |
| * 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 com.intellij.util.io; |
| |
| import com.intellij.openapi.diagnostic.Logger; |
| import org.jetbrains.annotations.Nullable; |
| import sun.misc.Cleaner; |
| import sun.nio.ch.DirectBuffer; |
| |
| import java.io.File; |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| |
| public abstract class DirectBufferWrapper extends ByteBufferWrapper { |
| protected static final Logger LOG = Logger.getInstance("#com.intellij.util.io.DirectBufferWrapper"); |
| |
| private volatile ByteBuffer myBuffer; |
| |
| protected DirectBufferWrapper(final File file, final long offset, final long length) { |
| super(file, offset, length); |
| } |
| |
| @Override |
| public ByteBuffer getCachedBuffer() { |
| return myBuffer; |
| } |
| |
| @Override |
| public ByteBuffer getBuffer() throws IOException { |
| ByteBuffer buffer = myBuffer; |
| if (buffer == null) { |
| myBuffer = buffer = create(); |
| } |
| return buffer; |
| } |
| |
| protected abstract ByteBuffer create() throws IOException; |
| |
| @Override |
| public void unmap() { |
| if (isDirty()) flush(); |
| if (myBuffer != null) disposeDirectBuffer((DirectBuffer)myBuffer); |
| myBuffer = null; |
| } |
| |
| static boolean disposeDirectBuffer(final DirectBuffer buffer) { |
| return AccessController.doPrivileged(new PrivilegedAction<Object>() { |
| @Override |
| @Nullable |
| public Object run() { |
| try { |
| Cleaner cleaner = buffer.cleaner(); |
| if (cleaner != null) cleaner.clean(); // Already cleaned otherwise |
| return null; |
| } |
| catch (Exception e) { |
| return buffer; |
| } |
| } |
| }) == null; |
| } |
| |
| } |