/*
* Copyright 2016 higherfrequencytrading.com
*
* Licensed 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 net.openhft.lang.io;
import sun.nio.ch.DirectBuffer;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
public class DirectByteBufferBytes extends NativeBytes implements IByteBufferBytes {
private ByteBuffer buffer;
public DirectByteBufferBytes(int capacity) {
this(ByteBuffer.allocateDirect(capacity).order(ByteOrder.nativeOrder()), 0, capacity);
}
public DirectByteBufferBytes(final ByteBuffer buffer) {
this(buffer, 0, buffer.capacity());
}
public DirectByteBufferBytes(final ByteBuffer buffer, int start, int capacity) {
super(
((DirectBuffer) buffer).address() + start,
((DirectBuffer) buffer).address() + capacity
);
this.buffer = buffer;
}
@Override
public ByteBuffer buffer() {
return buffer;
}
@Override
public ByteBuffer sliceAsByteBuffer(ByteBuffer toReuse) {
return sliceAsByteBuffer(toReuse, buffer);
}
protected DirectByteBufferBytes resize(int newCapacity, boolean cleanup, boolean preserveData) {
if(newCapacity != capacity()) {
final ByteBuffer oldBuffer = this.buffer;
final long oldAddress = this.startAddr;
final long oldPosition = position();
if(preserveData && (oldPosition > newCapacity)) {
throw new IllegalArgumentException(
"Capacity can't be less than currently used data (size=" + oldPosition
+ ", capacity=" + newCapacity + ")"
);
}
this.buffer = ByteBuffer.allocateDirect(newCapacity).order(ByteOrder.nativeOrder());
setStartPositionAddress(((DirectBuffer) buffer).address());
this.capacityAddr = this.startAddr + newCapacity;
this.limitAddr = this.capacityAddr;
if (preserveData && (oldPosition > 0)) {
UNSAFE.copyMemory(oldAddress, this.startAddr, Math.min(newCapacity, oldPosition));
this.positionAddr = this.startAddr + Math.min(newCapacity, oldPosition);
}
if(cleanup) {
IOTools.clean(oldBuffer);
}
}
return this;
}
}