/*
* 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.dht;
import java.util.Random;
import static org.junit.Assert.assertEquals;
import org.junit.Before;
import org.junit.Test;
import org.apache.cassandra.db.DecoratedKey;
public abstract class PartitionerTestCase<T extends Token> {
protected IPartitioner<T> partitioner;
public abstract void initPartitioner();
@Before
public void clean()
{
initPartitioner();
}
public T tok(String string)
{
return partitioner.getToken(string);
}
/**
* Recurses randomly to the given depth a few times.
*/
public void assertMidpoint(T left, T right, int depth)
{
Random rand = new Random();
for (int i = 0; i < 1000; i++)
{
assertMidpoint(left, right, rand, depth);
}
}
private void assertMidpoint(T left, T right, Random rand, int depth)
{
T mid = partitioner.midpoint(left, right);
assert new Range(left, right).contains(mid)
: "For " + left + "," + right + ": range did not contain mid:" + mid;
if (depth < 1)
return;
if (rand.nextBoolean())
assertMidpoint(left, mid, rand, depth-1);
else
assertMidpoint(mid, right, rand, depth-1);
}
@Test
public void testMidpoint()
{
assertMidpoint(tok("a"), tok("b"), 16);
assertMidpoint(tok("a"), tok("bbb"), 16);
}
@Test
public void testMidpointMinimum()
{
T mintoken = partitioner.getMinimumToken();
assert mintoken.compareTo(partitioner.midpoint(mintoken, mintoken)) != 0;
assertMidpoint(mintoken, tok("a"), 16);
assertMidpoint(mintoken, tok("aaa"), 16);
assertMidpoint(mintoken, mintoken, 126);
assertMidpoint(tok("a"), mintoken, 16);
}
@Test
public void testMidpointWrapping()
{
assertMidpoint(tok("b"), tok("a"), 16);
assertMidpoint(tok("bbb"), tok("a"), 16);
}
@Test
public void testDiskFormat()
{
String key = "key";
DecoratedKey<T> decKey = partitioner.decorateKey(key);
DecoratedKey<T> result = partitioner.convertFromDiskFormat(partitioner.convertToDiskFormat(decKey));
assertEquals(decKey, result);
}
@Test
public void testTokenFactoryBytes()
{
Token.TokenFactory factory = partitioner.getTokenFactory();
assert tok("a").compareTo(factory.fromByteArray(factory.toByteArray(tok("a")))) == 0;
}
@Test
public void testTokenFactoryStrings()
{
Token.TokenFactory factory = partitioner.getTokenFactory();
assert tok("a").compareTo(factory.fromString(factory.toString(tok("a")))) == 0;
}
}