org.apache.cassandra.db.rows.CellPath Maven / Gradle / Ivy
/*
* 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 org.apache.cassandra.db.rows;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.security.MessageDigest;
import java.util.Objects;
import org.apache.cassandra.io.util.DataOutputPlus;
import org.apache.cassandra.io.util.DataInputPlus;
import org.apache.cassandra.utils.ByteBufferUtil;
import org.apache.cassandra.utils.ObjectSizes;
import org.apache.cassandra.utils.memory.AbstractAllocator;
/**
* A path for a cell belonging to a complex column type (non-frozen collection or UDT).
*/
public abstract class CellPath
{
public static final CellPath BOTTOM = new EmptyCellPath();
public static final CellPath TOP = new EmptyCellPath();
public abstract int size();
public abstract ByteBuffer get(int i);
// The only complex paths we currently have are collections and UDTs, which both have a depth of one
public static CellPath create(ByteBuffer value)
{
assert value != null;
return new SingleItemCellPath(value);
}
public int dataSize()
{
int size = 0;
for (int i = 0; i < size(); i++)
size += get(i).remaining();
return size;
}
public void digest(MessageDigest digest)
{
for (int i = 0; i < size(); i++)
digest.update(get(i).duplicate());
}
public abstract CellPath copy(AbstractAllocator allocator);
public abstract long unsharedHeapSizeExcludingData();
@Override
public final int hashCode()
{
int result = 31;
for (int i = 0; i < size(); i++)
result += 31 * Objects.hash(get(i));
return result;
}
@Override
public final boolean equals(Object o)
{
if(!(o instanceof CellPath))
return false;
CellPath that = (CellPath)o;
if (this.size() != that.size())
return false;
for (int i = 0; i < size(); i++)
if (!Objects.equals(this.get(i), that.get(i)))
return false;
return true;
}
public interface Serializer
{
public void serialize(CellPath path, DataOutputPlus out) throws IOException;
public CellPath deserialize(DataInputPlus in) throws IOException;
public long serializedSize(CellPath path);
public void skip(DataInputPlus in) throws IOException;
}
private static class SingleItemCellPath extends CellPath
{
private static final long EMPTY_SIZE = ObjectSizes.measure(new SingleItemCellPath(ByteBufferUtil.EMPTY_BYTE_BUFFER));
protected final ByteBuffer value;
private SingleItemCellPath(ByteBuffer value)
{
this.value = value;
}
public int size()
{
return 1;
}
public ByteBuffer get(int i)
{
assert i == 0;
return value;
}
public CellPath copy(AbstractAllocator allocator)
{
return new SingleItemCellPath(allocator.clone(value));
}
public long unsharedHeapSizeExcludingData()
{
return EMPTY_SIZE + ObjectSizes.sizeOnHeapExcludingData(value);
}
}
private static class EmptyCellPath extends CellPath
{
public int size()
{
return 0;
}
public ByteBuffer get(int i)
{
throw new UnsupportedOperationException();
}
public CellPath copy(AbstractAllocator allocator)
{
return this;
}
public long unsharedHeapSizeExcludingData()
{
return 0;
}
}
}