/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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 org.apache.drill.exec.memory.BufferAllocator;
/**
* Allows us to decorate DrillBuf to make it expandable so that we can use them in the context of the Netty framework
* (thus supporting RPC level memory accounting).
*/
public class ExpandableByteBuf extends MutableWrappedByteBuf {
private final BufferAllocator allocator;
public ExpandableByteBuf(ByteBuf buffer, BufferAllocator allocator) {
super(buffer);
this.allocator = allocator;
}
@Override
public ByteBuf copy(int index, int length) {
return new ExpandableByteBuf(buffer.copy(index, length), allocator);
}
@Override
public ByteBuf capacity(int newCapacity) {
if (newCapacity > capacity()) {
ByteBuf newBuf = allocator.buffer(newCapacity);
newBuf.writeBytes(buffer, 0, buffer.capacity());
newBuf.readerIndex(buffer.readerIndex());
newBuf.writerIndex(buffer.writerIndex());
buffer.release();
buffer = newBuf;
return newBuf;
} else {
return super.capacity(newCapacity);
}
}
}