| /* |
| * 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.stress.generate; |
| |
| import java.util.concurrent.atomic.AtomicIntegerFieldUpdater; |
| |
| import org.apache.cassandra.stress.util.DynamicList; |
| |
| public class Seed implements Comparable<Seed> |
| { |
| |
| public final int visits; |
| public final long seed; |
| |
| private volatile DynamicList.Node poolNode; |
| private volatile int position; |
| |
| private static final AtomicIntegerFieldUpdater<Seed> positionUpdater = AtomicIntegerFieldUpdater.newUpdater(Seed.class, "position"); |
| |
| public int compareTo(Seed that) |
| { |
| return Long.compare(this.seed, that.seed); |
| } |
| |
| Seed(long seed, int visits) |
| { |
| this.seed = seed; |
| this.visits = visits; |
| } |
| |
| public int position() |
| { |
| return position; |
| } |
| |
| public int moveForwards(int rowCount) |
| { |
| return positionUpdater.getAndAdd(this, rowCount); |
| } |
| |
| public int hashCode() |
| { |
| return (int) seed; |
| } |
| |
| public boolean equals(Object that) |
| { |
| return that instanceof Seed && this.seed == ((Seed) that).seed; |
| } |
| |
| public boolean save(DynamicList<Seed> sampleFrom, int maxSize) |
| { |
| DynamicList.Node poolNode = sampleFrom.append(this, maxSize); |
| if (poolNode == null) |
| return false; |
| this.poolNode = poolNode; |
| return true; |
| } |
| |
| public boolean isSaved() |
| { |
| return poolNode != null; |
| } |
| |
| public void remove(DynamicList<Seed> sampleFrom) |
| { |
| sampleFrom.remove(poolNode); |
| } |
| } |