content: /*
   * 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.harry.gen.rng;
  
  import java.util.function.Consumer;
  import java.util.function.Function;
  
  import io.netty.util.concurrent.FastThreadLocal;
  import org.apache.cassandra.harry.gen.EntropySource;
  
  public class SeedableEntropySource
  {
      private static final FastThreadLocal<EntropySource> THREAD_LOCAL = new FastThreadLocal<>();
  
      public static <T> T computeWithSeed(long seed, Function<EntropySource, T> fn)
      {
          return fn.apply(entropySource(seed));
      }
  
      public static void doWithSeed(long seed, Consumer<EntropySource> fn)
      {
          fn.accept(entropySource(seed));
      }
  
      private static EntropySource entropySource(long seed)
      {
          EntropySource entropySource = THREAD_LOCAL.get();
          if (entropySource == null)
          {
              entropySource = new JdkRandomEntropySource(0);
              THREAD_LOCAL.set(entropySource);
          }
          entropySource.seed(seed);
          return entropySource;
      }
  }