org.apache.cassandra.dht.LocalPartitioner Maven / Gradle / Ivy
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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
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* Unless required by applicable law or agreed to in writing, software
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package org.apache.cassandra.dht;
import java.nio.ByteBuffer;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Random;
import org.apache.cassandra.db.DecoratedKey;
import org.apache.cassandra.db.CachedHashDecoratedKey;
import org.apache.cassandra.db.marshal.AbstractType;
import org.apache.cassandra.utils.ByteBufferUtil;
import org.apache.cassandra.utils.ObjectSizes;
import org.apache.cassandra.utils.memory.HeapAllocator;
public class LocalPartitioner implements IPartitioner
{
private static final long EMPTY_SIZE = ObjectSizes.measure(new LocalPartitioner(null).new LocalToken());
final AbstractType comparator; // package-private to avoid access workarounds in embedded LocalToken.
public LocalPartitioner(AbstractType comparator)
{
this.comparator = comparator;
}
public DecoratedKey decorateKey(ByteBuffer key)
{
return new CachedHashDecoratedKey(getToken(key), key);
}
public Token midpoint(Token left, Token right)
{
throw new UnsupportedOperationException();
}
public Token split(Token left, Token right, double ratioToLeft)
{
throw new UnsupportedOperationException();
}
public LocalToken getMinimumToken()
{
return new LocalToken(ByteBufferUtil.EMPTY_BYTE_BUFFER);
}
public LocalToken getToken(ByteBuffer key)
{
return new LocalToken(key);
}
public LocalToken getRandomToken()
{
throw new UnsupportedOperationException();
}
public LocalToken getRandomToken(Random random)
{
throw new UnsupportedOperationException();
}
public Token.TokenFactory getTokenFactory()
{
return tokenFactory;
}
private final Token.TokenFactory tokenFactory = new Token.TokenFactory()
{
public ByteBuffer toByteArray(Token token)
{
return ((LocalToken)token).token;
}
public Token fromByteArray(ByteBuffer bytes)
{
return new LocalToken(bytes);
}
public String toString(Token token)
{
return comparator.getString(((LocalToken)token).token);
}
public void validate(String token)
{
comparator.validate(comparator.fromString(token));
}
public Token fromString(String string)
{
return new LocalToken(comparator.fromString(string));
}
};
public boolean preservesOrder()
{
return true;
}
public Map describeOwnership(List sortedTokens)
{
return Collections.singletonMap((Token)getMinimumToken(), new Float(1.0));
}
public AbstractType getTokenValidator()
{
return comparator;
}
public AbstractType partitionOrdering()
{
return comparator;
}
public class LocalToken extends ComparableObjectToken
{
static final long serialVersionUID = 8437543776403014875L;
private LocalToken()
{
super(null);
}
public LocalToken(ByteBuffer token)
{
super(HeapAllocator.instance.clone(token));
}
@Override
public String toString()
{
return comparator.getString(token);
}
@Override
public int compareTo(Token o)
{
assert getPartitioner() == o.getPartitioner();
return comparator.compare(token, ((LocalToken) o).token);
}
@Override
public int hashCode()
{
final int prime = 31;
return prime + token.hashCode();
}
@Override
public boolean equals(Object obj)
{
if (this == obj)
return true;
if (!(obj instanceof LocalToken))
return false;
LocalToken other = (LocalToken) obj;
return token.equals(other.token);
}
@Override
public IPartitioner getPartitioner()
{
return LocalPartitioner.this;
}
@Override
public long getHeapSize()
{
return EMPTY_SIZE + ObjectSizes.sizeOnHeapOf(token);
}
}
}