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* to you under the Apache License, Version 2.0 (the
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* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
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package com.datastax.oss.driver.internal.core.metadata.token;
import com.datastax.oss.driver.api.core.metadata.Node;
import com.datastax.oss.driver.api.core.metadata.token.Token;
import com.datastax.oss.driver.shaded.guava.common.annotations.VisibleForTesting;
import com.datastax.oss.driver.shaded.guava.common.base.Preconditions;
import com.datastax.oss.driver.shaded.guava.common.collect.ImmutableMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import net.jcip.annotations.ThreadSafe;
@ThreadSafe
class SimpleReplicationStrategy implements ReplicationStrategy {
private final ReplicationFactor replicationFactor;
SimpleReplicationStrategy(Map replicationConfig) {
this(extractReplicationFactor(replicationConfig));
}
@VisibleForTesting
SimpleReplicationStrategy(ReplicationFactor replicationFactor) {
this.replicationFactor = replicationFactor;
}
@Override
public Map> computeReplicasByToken(
Map tokenToPrimary, List ring) {
int rf = Math.min(replicationFactor.fullReplicas(), ring.size());
ImmutableMap.Builder> result = ImmutableMap.builder();
CanonicalNodeSetBuilder replicasBuilder = new CanonicalNodeSetBuilder();
for (int i = 0; i < ring.size(); i++) {
replicasBuilder.clear();
for (int j = 0; j < ring.size() && replicasBuilder.size() < rf; j++) {
replicasBuilder.add(tokenToPrimary.get(getTokenWrapping(i + j, ring)));
}
result.put(ring.get(i), replicasBuilder.build());
}
return result.build();
}
private static Token getTokenWrapping(int i, List ring) {
return ring.get(i % ring.size());
}
private static ReplicationFactor extractReplicationFactor(Map replicationConfig) {
String factorString = replicationConfig.get("replication_factor");
Preconditions.checkNotNull(factorString, "Missing replication factor in " + replicationConfig);
return ReplicationFactor.fromString(factorString);
}
}