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/*
* 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 io.trino.plugin.cassandra;
import com.datastax.oss.driver.api.core.metadata.token.Token;
import com.datastax.oss.driver.internal.core.metadata.token.Murmur3Token;
import java.math.BigInteger;
import static java.math.BigInteger.ZERO;
public final class Murmur3PartitionerTokenRing
implements TokenRing
{
public static final Murmur3PartitionerTokenRing INSTANCE = new Murmur3PartitionerTokenRing();
private static final long MIN_TOKEN = Long.MIN_VALUE;
private static final long MAX_TOKEN = Long.MAX_VALUE;
private static final BigInteger TOTAL_TOKEN_COUNT = BigInteger.valueOf(MAX_TOKEN).subtract(BigInteger.valueOf(MIN_TOKEN));
private Murmur3PartitionerTokenRing() {}
@Override
public double getRingFraction(Token start, Token end)
{
return getTokenCountInRange(start, end).doubleValue() / TOTAL_TOKEN_COUNT.doubleValue();
}
@Override
public BigInteger getTokenCountInRange(Token startToken, Token endToken)
{
long start = ((Murmur3Token) startToken).getValue();
long end = ((Murmur3Token) endToken).getValue();
if (start == end) {
if (start == MIN_TOKEN) {
return TOTAL_TOKEN_COUNT;
}
return ZERO;
}
BigInteger result = BigInteger.valueOf(end).subtract(BigInteger.valueOf(start));
if (end <= start) {
result = result.add(TOTAL_TOKEN_COUNT);
}
return result;
}
}