/*
* The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
* (the "License"). You may not use this work except in compliance with the License, which is
* available at www.apache.org/licenses/LICENSE-2.0
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
* either express or implied, as more fully set forth in the License.
*
* See the NOTICE file distributed with this work for information regarding copyright ownership.
*/
package alluxio.network.protocol.databuffer;
import alluxio.util.io.BufferUtils;
import com.google.common.base.Preconditions;
import io.netty.buffer.Unpooled;
import java.nio.ByteBuffer;
/**
* A DataBuffer with the underlying data being a {@link ByteBuffer}. If the backing ByteBuffer is
* a direct ByteBuffer, {@link #release()} should only be called when all references to the
* object are finished with it. For this reason, it is not recommended to share objects of this
* class unless reference counting is implemented by the users of this class.
*/
public final class DataByteBuffer implements DataBuffer {
private final ByteBuffer mBuffer;
private final long mLength;
/**
*
* @param buffer The ByteBuffer representing the data
* @param length The length of the ByteBuffer
*/
public DataByteBuffer(ByteBuffer buffer, long length) {
mBuffer = Preconditions.checkNotNull(buffer, "buffer");
mLength = length;
}
@Override
public Object getNettyOutput() {
return Unpooled.wrappedBuffer(mBuffer);
}
@Override
public long getLength() {
return mLength;
}
@Override
public ByteBuffer getReadOnlyByteBuffer() {
ByteBuffer buffer = mBuffer.asReadOnlyBuffer();
buffer.position(0);
return buffer;
}
@Override
public void readBytes(byte[] dst, int dstIndex, int length) {
mBuffer.get(dst, dstIndex, length);
}
@Override
public int readableBytes() {
return mBuffer.remaining();
}
@Override
public void release() {
if (mBuffer.isDirect()) {
BufferUtils.cleanDirectBuffer(mBuffer);
}
}
}