import java.util.concurrent.TimeUnit;
import org.jspecify.annotations.Nullable;

/**
 * A {@link BlockingDeque} which forwards all its method calls to another {@code BlockingDeque}.
 * Subclasses should override one or more methods to modify the behavior of the backing deque as
 * desired per the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *

  private static final String NONALPHA = "0123456789`~-_=+[]{}|;:',.<>/?!@#$%^&*()\"\\";

  @Param({"20", "2000"})
  int size;

  @Param({"2", "20"})
  int nonAlphaRatio; // one non-alpha char per this many chars

  @Param boolean noWorkToDo;

  Random random;
  String testString;

  @BeforeExperiment
  void setUp() {

<!--
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

/*
 * 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
 *

/*
 * 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
 *

/*
 * 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
 *

## Example { #example }

For a simple example, let's consider a file structure similar to the one described in [Bigger Applications](../tutorial/bigger-applications.md){.internal-link target=_blank} and [Testing](../tutorial/testing.md){.internal-link target=_blank}:

```
.
├── app
│   ├── __init__.py
│   ├── main.py

/*
 * 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
 *

  private static boolean isDeclaredThreadSafe(Method method) {
    return method.getAnnotation(AllowConcurrentEvents.class) != null;
  }

  /**
   * Subscriber that synchronizes invocations of a method to ensure that only one thread may enter
   * the method at a time.
   */
  @VisibleForTesting
  static final class SynchronizedSubscriber extends Subscriber {

    private SynchronizedSubscriber(EventBus bus, Object target, Method method) {

                return wrap(delegate);
              }
            });
  }

  public void testEquals() {
    SortedMultiset<String> set1 = ImmutableSortedMultiset.of("one");
    SortedMultiset<String> set2 = ImmutableSortedMultiset.of("two");
    new EqualsTester()
        .addEqualityGroup(set1, wrap(set1), wrap(set1))
        .addEqualityGroup(set2, wrap(set2))
        .testEquals();