org.apache.cassandra.utils.memory.ContextAllocator Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* 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
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*/
package org.apache.cassandra.utils.memory;
import java.nio.ByteBuffer;
import org.apache.cassandra.utils.ByteBufferUtil;
import org.apache.cassandra.utils.concurrent.OpOrder;
/**
* Wraps calls to a PoolAllocator with the provided writeOp. Also doubles as a Function that clones Cells
* using itself
*/
public final class ContextAllocator extends AbstractAllocator
{
private final OpOrder.Group opGroup;
private final MemtableBufferAllocator allocator;
public ContextAllocator(OpOrder.Group opGroup, MemtableBufferAllocator allocator)
{
this.opGroup = opGroup;
this.allocator = allocator;
}
@Override
public ByteBuffer clone(ByteBuffer buffer)
{
assert buffer != null;
if (buffer.remaining() == 0)
return ByteBufferUtil.EMPTY_BYTE_BUFFER;
ByteBuffer cloned = allocate(buffer.remaining());
cloned.mark();
cloned.put(buffer.duplicate());
cloned.reset();
return cloned;
}
public ByteBuffer allocate(int size)
{
return allocator.allocate(size, opGroup);
}
}