/*
 * Copyright 2013 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.nio.ByteBuffer;


Read-only ByteBuf which wraps a read-only direct ByteBuffer and use unsafe for best performance.
/** * Read-only ByteBuf which wraps a read-only direct ByteBuffer and use unsafe for best performance. */
final class ReadOnlyUnsafeDirectByteBuf extends ReadOnlyByteBufferBuf { private final long memoryAddress; ReadOnlyUnsafeDirectByteBuf(ByteBufAllocator allocator, ByteBuffer byteBuffer) { super(allocator, byteBuffer); // Use buffer as the super class will slice the passed in ByteBuffer which means the memoryAddress // may be different if the position != 0. memoryAddress = PlatformDependent.directBufferAddress(buffer); } @Override protected byte _getByte(int index) { return UnsafeByteBufUtil.getByte(addr(index)); } @Override protected short _getShort(int index) { return UnsafeByteBufUtil.getShort(addr(index)); } @Override protected int _getUnsignedMedium(int index) { return UnsafeByteBufUtil.getUnsignedMedium(addr(index)); } @Override protected int _getInt(int index) { return UnsafeByteBufUtil.getInt(addr(index)); } @Override protected long _getLong(int index) { return UnsafeByteBufUtil.getLong(addr(index)); } @Override public ByteBuf getBytes(int index, ByteBuf dst, int dstIndex, int length) { checkIndex(index, length); if (dst == null) { throw new NullPointerException("dst"); } if (dstIndex < 0 || dstIndex > dst.capacity() - length) { throw new IndexOutOfBoundsException("dstIndex: " + dstIndex); } if (dst.hasMemoryAddress()) { PlatformDependent.copyMemory(addr(index), dst.memoryAddress() + dstIndex, length); } else if (dst.hasArray()) { PlatformDependent.copyMemory(addr(index), dst.array(), dst.arrayOffset() + dstIndex, length); } else { dst.setBytes(dstIndex, this, index, length); } return this; } @Override public ByteBuf getBytes(int index, byte[] dst, int dstIndex, int length) { checkIndex(index, length); if (dst == null) { throw new NullPointerException("dst"); } if (dstIndex < 0 || dstIndex > dst.length - length) { throw new IndexOutOfBoundsException(String.format( "dstIndex: %d, length: %d (expected: range(0, %d))", dstIndex, length, dst.length)); } if (length != 0) { PlatformDependent.copyMemory(addr(index), dst, dstIndex, length); } return this; } @Override public ByteBuf getBytes(int index, ByteBuffer dst) { checkIndex(index); if (dst == null) { throw new NullPointerException("dst"); } int bytesToCopy = Math.min(capacity() - index, dst.remaining()); ByteBuffer tmpBuf = internalNioBuffer(); tmpBuf.clear().position(index).limit(index + bytesToCopy); dst.put(tmpBuf); return this; } @Override public ByteBuf copy(int index, int length) { checkIndex(index, length); ByteBuf copy = alloc().directBuffer(length, maxCapacity()); if (length != 0) { if (copy.hasMemoryAddress()) { PlatformDependent.copyMemory(addr(index), copy.memoryAddress(), length); copy.setIndex(0, length); } else { copy.writeBytes(this, index, length); } } return copy; } @Override public boolean hasMemoryAddress() { return true; } @Override public long memoryAddress() { return memoryAddress; } private long addr(int index) { return memoryAddress + index; } }