/*
* 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 java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.channels.GatheringByteChannel;
import java.nio.channels.ScatteringByteChannel;
/**
* A derived buffer which exposes its parent's sub-region only. It is
* recommended to use {@link ByteBuf#slice()} and
* {@link ByteBuf#slice(int, int)} instead of calling the constructor
* explicitly.
*/
public class SlicedByteBuf extends AbstractDerivedByteBuf {
private final ByteBuf buffer;
private final int adjustment;
private final int length;
public SlicedByteBuf(ByteBuf buffer, int index, int length) {
super(length);
if (index < 0 || index > buffer.capacity() - length) {
throw new IndexOutOfBoundsException(buffer + ".slice(" + index + ", " + length + ')');
}
if (buffer instanceof SlicedByteBuf) {
this.buffer = ((SlicedByteBuf) buffer).buffer;
adjustment = ((SlicedByteBuf) buffer).adjustment + index;
} else if (buffer instanceof DuplicatedByteBuf) {
this.buffer = buffer.unwrap();
adjustment = index;
} else {
this.buffer = buffer;
adjustment = index;
}
this.length = length;
writerIndex(length);
}
@Override
public ByteBuf unwrap() {
return buffer;
}
@Override
public ByteBufAllocator alloc() {
return buffer.alloc();
}
@Override
public ByteOrder order() {
return buffer.order();
}
@Override
public boolean isDirect() {
return buffer.isDirect();
}
@Override
public int capacity() {
return length;
}
@Override
public ByteBuf capacity(int newCapacity) {
throw new UnsupportedOperationException("sliced buffer");
}
@Override
public boolean hasArray() {
return buffer.hasArray();
}
@Override
public byte[] array() {
return buffer.array();
}
@Override
public int arrayOffset() {
return buffer.arrayOffset() + adjustment;
}
@Override
public boolean hasMemoryAddress() {
return buffer.hasMemoryAddress();
}
@Override
public long memoryAddress() {
return buffer.memoryAddress() + adjustment;
}
@Override
protected byte _getByte(int index) {
return buffer.getByte(index + adjustment);
}
@Override
protected short _getShort(int index) {
return buffer.getShort(index + adjustment);
}
@Override
protected int _getUnsignedMedium(int index) {
return buffer.getUnsignedMedium(index + adjustment);
}
@Override
protected int _getInt(int index) {
return buffer.getInt(index + adjustment);
}
@Override
protected long _getLong(int index) {
return buffer.getLong(index + adjustment);
}
@Override
public ByteBuf duplicate() {
ByteBuf duplicate = buffer.slice(adjustment, length);
duplicate.setIndex(readerIndex(), writerIndex());
return duplicate;
}
@Override
public ByteBuf copy(int index, int length) {
checkIndex(index, length);
return buffer.copy(index + adjustment, length);
}
@Override
public ByteBuf slice(int index, int length) {
checkIndex(index, length);
if (length == 0) {
return Unpooled.EMPTY_BUFFER;
}
return buffer.slice(index + adjustment, length);
}
@Override
public ByteBuf getBytes(int index, ByteBuf dst, int dstIndex, int length) {
checkIndex(index, length);
buffer.getBytes(index + adjustment, dst, dstIndex, length);
return this;
}
@Override
public ByteBuf getBytes(int index, byte[] dst, int dstIndex, int length) {
checkIndex(index, length);
buffer.getBytes(index + adjustment, dst, dstIndex, length);
return this;
}
@Override
public ByteBuf getBytes(int index, ByteBuffer dst) {
checkIndex(index, dst.remaining());
buffer.getBytes(index + adjustment, dst);
return this;
}
@Override
protected void _setByte(int index, int value) {
buffer.setByte(index + adjustment, value);
}
@Override
protected void _setShort(int index, int value) {
buffer.setShort(index + adjustment, value);
}
@Override
protected void _setMedium(int index, int value) {
buffer.setMedium(index + adjustment, value);
}
@Override
protected void _setInt(int index, int value) {
buffer.setInt(index + adjustment, value);
}
@Override
protected void _setLong(int index, long value) {
buffer.setLong(index + adjustment, value);
}
@Override
public ByteBuf setBytes(int index, byte[] src, int srcIndex, int length) {
checkIndex(index, length);
buffer.setBytes(index + adjustment, src, srcIndex, length);
return this;
}
@Override
public ByteBuf setBytes(int index, ByteBuf src, int srcIndex, int length) {
checkIndex(index, length);
buffer.setBytes(index + adjustment, src, srcIndex, length);
return this;
}
@Override
public ByteBuf setBytes(int index, ByteBuffer src) {
checkIndex(index, src.remaining());
buffer.setBytes(index + adjustment, src);
return this;
}
@Override
public ByteBuf getBytes(int index, OutputStream out, int length) throws IOException {
checkIndex(index, length);
buffer.getBytes(index + adjustment, out, length);
return this;
}
@Override
public int getBytes(int index, GatheringByteChannel out, int length) throws IOException {
checkIndex(index, length);
return buffer.getBytes(index + adjustment, out, length);
}
@Override
public int setBytes(int index, InputStream in, int length) throws IOException {
checkIndex(index, length);
return buffer.setBytes(index + adjustment, in, length);
}
@Override
public int setBytes(int index, ScatteringByteChannel in, int length) throws IOException {
checkIndex(index, length);
return buffer.setBytes(index + adjustment, in, length);
}
@Override
public int nioBufferCount() {
return buffer.nioBufferCount();
}
@Override
public ByteBuffer nioBuffer(int index, int length) {
checkIndex(index, length);
return buffer.nioBuffer(index + adjustment, length);
}
@Override
public ByteBuffer[] nioBuffers(int index, int length) {
checkIndex(index, length);
return buffer.nioBuffers(index + adjustment, length);
}
@Override
public ByteBuffer internalNioBuffer(int index, int length) {
checkIndex(index, length);
return nioBuffer(index, length);
}
@Override
public int forEachByte(int index, int length, ByteBufProcessor processor) {
int ret = buffer.forEachByte(index + adjustment, length, processor);
if (ret >= adjustment) {
return ret - adjustment;
} else {
return -1;
}
}
@Override
public int forEachByteDesc(int index, int length, ByteBufProcessor processor) {
int ret = buffer.forEachByteDesc(index + adjustment, length, processor);
if (ret >= adjustment) {
return ret - adjustment;
} else {
return -1;
}
}
}