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.kafka.common.test.api;
  
  import java.util.List;
  import java.util.Set;
  import java.util.function.Predicate;
  import java.util.stream.Collectors;
  
  public interface DetectThreadLeak {
      /**
       * @return the new threads after `DetectThreadLeak` is created
       */
      List<Thread> newThreads();
  
      /**
       * Creates an instance of {@link DetectThreadLeak} that filters threads based on a given predicate.
       * This method captures the current state of threads that match the predicate at the time of invocation
       * and provides a way to detect new threads that match the predicate but were not present at the initial capture.
       *
       * @param predicate A {@link Predicate<Thread>} used to filter threads. Only threads that satisfy
       *                  the predicate are considered for detection.
       * @return An instance of {@link DetectThreadLeak} that can be used to detect new threads matching
       *         the predicate that were not present at the time of this method's invocation.
       *         The {@link DetectThreadLeak#newThreads()} method of the returned instance will return a list
       *         of new threads that match the predicate and have been started after this method was called.
       */
      static DetectThreadLeak of(Predicate<Thread> predicate) {
          Set<Long> before = Thread.getAllStackTraces().keySet()
                  .stream().filter(predicate).map(Thread::getId).collect(Collectors.toSet());
          return () -> Thread.getAllStackTraces().keySet()
                  .stream().filter(predicate)
                  .filter(t -> !before.contains(t.getId()))
                  .collect(Collectors.toList());
      }
  }
  