/*
* Copyright 2009 Red Hat, Inc.
*
* Red Hat 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 org.jboss.netty.buffer;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.GatheringByteChannel;
import java.nio.channels.ScatteringByteChannel;
/**
* A skeletal implementation for Java heap buffers.
*
* @author The Netty Project
* @author Trustin Lee
*
* @version $Rev$, $Date$
*/
public abstract class HeapChannelBuffer extends AbstractChannelBuffer {
/**
* The underlying heap byte array that this buffer is wrapping.
*/
protected final byte[] array;
/**
* Creates a new heap buffer with a newly allocated byte array.
*
* @param length the length of the new byte array
*/
public HeapChannelBuffer(int length) {
this(new byte[length], 0, 0);
}
/**
* Creates a new heap buffer with an existing byte array.
*
* @param array the byte array to wrap
*/
public HeapChannelBuffer(byte[] array) {
this(array, 0, array.length);
}
/**
* Creates a new heap buffer with an existing byte array.
*
* @param array the byte array to wrap
* @param readerIndex the initial reader index of this buffer
* @param writerIndex the initial writer index of this buffer
*/
protected HeapChannelBuffer(byte[] array, int readerIndex, int writerIndex) {
if (array == null) {
throw new NullPointerException("array");
}
this.array = array;
setIndex(readerIndex, writerIndex);
}
public int capacity() {
return array.length;
}
public boolean hasArray() {
return true;
}
public byte[] array() {
return array;
}
public int arrayOffset() {
return 0;
}
public byte getByte(int index) {
return array[index];
}
public void getBytes(int index, ChannelBuffer dst, int dstIndex, int length) {
if (dst instanceof HeapChannelBuffer) {
getBytes(index, ((HeapChannelBuffer) dst).array, dstIndex, length);
} else {
dst.setBytes(dstIndex, array, index, length);
}
}
public void getBytes(int index, byte[] dst, int dstIndex, int length) {
System.arraycopy(array, index, dst, dstIndex, length);
}
public void getBytes(int index, ByteBuffer dst) {
dst.put(array, index, Math.min(capacity() - index, dst.remaining()));
}
public void getBytes(int index, OutputStream out, int length)
throws IOException {
out.write(array, index, length);
}
public int getBytes(int index, GatheringByteChannel out, int length)
throws IOException {
return out.write(ByteBuffer.wrap(array, index, length));
}
public void setByte(int index, byte value) {
array[index] = value;
}
public void setBytes(int index, ChannelBuffer src, int srcIndex, int length) {
if (src instanceof HeapChannelBuffer) {
setBytes(index, ((HeapChannelBuffer) src).array, srcIndex, length);
} else {
src.getBytes(srcIndex, array, index, length);
}
}
public void setBytes(int index, byte[] src, int srcIndex, int length) {
System.arraycopy(src, srcIndex, array, index, length);
}
public void setBytes(int index, ByteBuffer src) {
src.get(array, index, src.remaining());
}
public int setBytes(int index, InputStream in, int length) throws IOException {
int readBytes = 0;
do {
int localReadBytes = in.read(array, index, length);
if (localReadBytes < 0) {
if (readBytes == 0) {
return -1;
} else {
break;
}
}
readBytes += localReadBytes;
index += localReadBytes;
length -= localReadBytes;
} while (length > 0);
return readBytes;
}
public int setBytes(int index, ScatteringByteChannel in, int length) throws IOException {
ByteBuffer buf = ByteBuffer.wrap(array, index, length);
int readBytes = 0;
do {
int localReadBytes;
try {
localReadBytes = in.read(buf);
} catch (ClosedChannelException e) {
localReadBytes = -1;
}
if (localReadBytes < 0) {
if (readBytes == 0) {
return -1;
} else {
break;
}
} else if (localReadBytes == 0) {
break;
}
readBytes += localReadBytes;
} while (readBytes < length);
return readBytes;
}
public ChannelBuffer slice(int index, int length) {
if (index == 0) {
if (length == 0) {
return ChannelBuffers.EMPTY_BUFFER;
}
if (length == array.length) {
return duplicate();
} else {
return new TruncatedChannelBuffer(this, length);
}
} else {
if (length == 0) {
return ChannelBuffers.EMPTY_BUFFER;
}
return new SlicedChannelBuffer(this, index, length);
}
}
public ByteBuffer toByteBuffer(int index, int length) {
return ByteBuffer.wrap(array, index, length).order(order());
}
}