package com.netflix.astyanax.partitioner;
import java.math.BigInteger;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import com.google.common.collect.Lists;
import com.netflix.astyanax.Serializer;
import com.netflix.astyanax.connectionpool.TokenRange;
import com.netflix.astyanax.connectionpool.impl.TokenRangeImpl;
public class Murmur3Partitioner implements Partitioner {
public static final BigInteger MINIMUM = new BigInteger(Long.toString(Long.MIN_VALUE));
public static final BigInteger MAXIMUM = new BigInteger(Long.toString(Long.MAX_VALUE));
public static final BigInteger ONE = new BigInteger("1");
private static final org.apache.cassandra.dht.Murmur3Partitioner partitioner = new org.apache.cassandra.dht.Murmur3Partitioner();
private static final Murmur3Partitioner instance = new Murmur3Partitioner();
public static Partitioner get() {
return instance;
}
private Murmur3Partitioner() {
}
@Override
public String getMinToken() {
return MINIMUM.toString();
}
@Override
public String getMaxToken() {
return MAXIMUM.toString();
}
@Override
public List<TokenRange> splitTokenRange(String first, String last, int count) {
if (first.equals(last)) {
last = getTokenMinusOne(last);
}
List<TokenRange> tokens = Lists.newArrayList();
List<String> splits = splitRange(new BigInteger(first), new BigInteger(last), count);
Iterator<String> iter = splits.iterator();
String current = iter.next();
while (iter.hasNext()) {
String next = iter.next();
tokens.add(new TokenRangeImpl(current, next, new ArrayList<String>()));
current = next;
}
return tokens;
}
@Override
public List<TokenRange> splitTokenRange(int count) {
return splitTokenRange(getMinToken(), getMaxToken(), count);
}
@Override
public String getTokenForKey(ByteBuffer key) {
return partitioner.getToken(key).toString();
}
public <T> String getTokenForKey(T key, Serializer<T> serializer) {
return partitioner.getToken(serializer.toByteBuffer(key)).toString();
}
@Override
public String getTokenMinusOne(String token) {
Long lToken = Long.parseLong(token);
// if zero rotate to the Maximum else minus one.
if (lToken.equals(MINIMUM))
return MAXIMUM.toString();
else
return Long.toString(lToken - 1);
}
public static List<String> splitRange(BigInteger first, BigInteger last, int count) {
List<String> tokens = Lists.newArrayList();
tokens.add(first.toString());
BigInteger delta = (last.subtract(first).divide(BigInteger.valueOf((long)count)));
BigInteger current = first;
for (int i = 0; i < count-1; i++) {
current = current.add(delta);
tokens.add(current.toString());
}
tokens.add(last.toString());
return tokens;
}
}