Java tutorial
/* * Copyright 2012 The Netty Project * * The Netty Project licenses this file to you 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 io.netty.buffer; import io.netty.util.internal.PlatformDependent; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.nio.ByteBuffer; /** * A NIO {@link ByteBuffer} based buffer. It is recommended to use * {@link UnpooledByteBufAllocator#directBuffer(int, int)}, {@link Unpooled#directBuffer(int)} and * {@link Unpooled#wrappedBuffer(ByteBuffer)} instead of calling the constructor explicitly.} */ public class UnpooledUnsafeDirectByteBuf extends UnpooledDirectByteBuf { long memoryAddress; /** * Creates a new direct buffer. * * @param initialCapacity the initial capacity of the underlying direct buffer * @param maxCapacity the maximum capacity of the underlying direct buffer */ public UnpooledUnsafeDirectByteBuf(ByteBufAllocator alloc, int initialCapacity, int maxCapacity) { super(alloc, initialCapacity, maxCapacity); } /** * Creates a new direct buffer by wrapping the specified initial buffer. * * @param maxCapacity the maximum capacity of the underlying direct buffer */ protected UnpooledUnsafeDirectByteBuf(ByteBufAllocator alloc, ByteBuffer initialBuffer, int maxCapacity) { // We never try to free the buffer if it was provided by the end-user as we not know if this is an duplicate or // an slice. This is done to prevent an IllegalArgumentException when using Java9 as Unsafe.invokeCleaner(...) // will check if the given buffer is either an duplicate or slice and in this case throw an // IllegalArgumentException. // // See http://hg.openjdk.java.net/jdk9/hs-demo/jdk/file/0d2ab72ba600/src/jdk.unsupported/share/classes/ // sun/misc/Unsafe.java#l1250 // // We also call slice() explicitly here to preserve behaviour with previous netty releases. super(alloc, initialBuffer, maxCapacity, /* doFree = */ false, /* slice = */ true); } UnpooledUnsafeDirectByteBuf(ByteBufAllocator alloc, ByteBuffer initialBuffer, int maxCapacity, boolean doFree) { super(alloc, initialBuffer, maxCapacity, doFree, false); } @Override final void setByteBuffer(ByteBuffer buffer, boolean tryFree) { super.setByteBuffer(buffer, tryFree); memoryAddress = PlatformDependent.directBufferAddress(buffer); } @Override public boolean hasMemoryAddress() { return true; } @Override public long memoryAddress() { ensureAccessible(); return memoryAddress; } @Override public byte getByte(int index) { checkIndex(index); return _getByte(index); } @Override protected byte _getByte(int index) { return UnsafeByteBufUtil.getByte(addr(index)); } @Override public short getShort(int index) { checkIndex(index, 2); return _getShort(index); } @Override protected short _getShort(int index) { return UnsafeByteBufUtil.getShort(addr(index)); } @Override protected short _getShortLE(int index) { return UnsafeByteBufUtil.getShortLE(addr(index)); } @Override public int getUnsignedMedium(int index) { checkIndex(index, 3); return _getUnsignedMedium(index); } @Override protected int _getUnsignedMedium(int index) { return UnsafeByteBufUtil.getUnsignedMedium(addr(index)); } @Override protected int _getUnsignedMediumLE(int index) { return UnsafeByteBufUtil.getUnsignedMediumLE(addr(index)); } @Override public int getInt(int index) { checkIndex(index, 4); return _getInt(index); } @Override protected int _getInt(int index) { return UnsafeByteBufUtil.getInt(addr(index)); } @Override protected int _getIntLE(int index) { return UnsafeByteBufUtil.getIntLE(addr(index)); } @Override public long getLong(int index) { checkIndex(index, 8); return _getLong(index); } @Override protected long _getLong(int index) { return UnsafeByteBufUtil.getLong(addr(index)); } @Override protected long _getLongLE(int index) { return UnsafeByteBufUtil.getLongLE(addr(index)); } @Override public ByteBuf getBytes(int index, ByteBuf dst, int dstIndex, int length) { UnsafeByteBufUtil.getBytes(this, addr(index), index, dst, dstIndex, length); return this; } @Override void getBytes(int index, byte[] dst, int dstIndex, int length, boolean internal) { UnsafeByteBufUtil.getBytes(this, addr(index), index, dst, dstIndex, length); } @Override void getBytes(int index, ByteBuffer dst, boolean internal) { UnsafeByteBufUtil.getBytes(this, addr(index), index, dst); } @Override public ByteBuf setByte(int index, int value) { checkIndex(index); _setByte(index, value); return this; } @Override protected void _setByte(int index, int value) { UnsafeByteBufUtil.setByte(addr(index), value); } @Override public ByteBuf setShort(int index, int value) { checkIndex(index, 2); _setShort(index, value); return this; } @Override protected void _setShort(int index, int value) { UnsafeByteBufUtil.setShort(addr(index), value); } @Override protected void _setShortLE(int index, int value) { UnsafeByteBufUtil.setShortLE(addr(index), value); } @Override public ByteBuf setMedium(int index, int value) { checkIndex(index, 3); _setMedium(index, value); return this; } @Override protected void _setMedium(int index, int value) { UnsafeByteBufUtil.setMedium(addr(index), value); } @Override protected void _setMediumLE(int index, int value) { UnsafeByteBufUtil.setMediumLE(addr(index), value); } @Override public ByteBuf setInt(int index, int value) { checkIndex(index, 4); _setInt(index, value); return this; } @Override protected void _setInt(int index, int value) { UnsafeByteBufUtil.setInt(addr(index), value); } @Override protected void _setIntLE(int index, int value) { UnsafeByteBufUtil.setIntLE(addr(index), value); } @Override public ByteBuf setLong(int index, long value) { checkIndex(index, 8); _setLong(index, value); return this; } @Override protected void _setLong(int index, long value) { UnsafeByteBufUtil.setLong(addr(index), value); } @Override protected void _setLongLE(int index, long value) { UnsafeByteBufUtil.setLongLE(addr(index), value); } @Override public ByteBuf setBytes(int index, ByteBuf src, int srcIndex, int length) { UnsafeByteBufUtil.setBytes(this, addr(index), index, src, srcIndex, length); return this; } @Override public ByteBuf setBytes(int index, byte[] src, int srcIndex, int length) { UnsafeByteBufUtil.setBytes(this, addr(index), index, src, srcIndex, length); return this; } @Override public ByteBuf setBytes(int index, ByteBuffer src) { UnsafeByteBufUtil.setBytes(this, addr(index), index, src); return this; } @Override void getBytes(int index, OutputStream out, int length, boolean internal) throws IOException { UnsafeByteBufUtil.getBytes(this, addr(index), index, out, length); } @Override public int setBytes(int index, InputStream in, int length) throws IOException { return UnsafeByteBufUtil.setBytes(this, addr(index), index, in, length); } @Override public ByteBuf copy(int index, int length) { return UnsafeByteBufUtil.copy(this, addr(index), index, length); } final long addr(int index) { return memoryAddress + index; } @Override protected SwappedByteBuf newSwappedByteBuf() { if (PlatformDependent.isUnaligned()) { // Only use if unaligned access is supported otherwise there is no gain. return new UnsafeDirectSwappedByteBuf(this); } return super.newSwappedByteBuf(); } @Override public ByteBuf setZero(int index, int length) { checkIndex(index, length); UnsafeByteBufUtil.setZero(addr(index), length); return this; } @Override public ByteBuf writeZero(int length) { ensureWritable(length); int wIndex = writerIndex; UnsafeByteBufUtil.setZero(addr(wIndex), length); writerIndex = wIndex + length; return this; } }