import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Tester to ensure forwarding wrapper works by delegating calls to the corresponding method with
 * the same parameters forwarded and return value forwarded back or exception propagated as is.
 *
 * <p>For example:
 *
 * {@snippet :

import java.util.Collection;
import java.util.Iterator;
import java.util.Objects;
import org.jspecify.annotations.Nullable;

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

import java.util.Collection;
import java.util.Iterator;
import java.util.Objects;
import org.jspecify.annotations.Nullable;

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

import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import org.jspecify.annotations.Nullable;

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

    void testInitialState() {
        assertEquals(SimpleCircuitBreaker.State.CLOSED, circuitBreaker.getState());
        assertTrue(circuitBreaker.allowsRequests());
    }

    @Test
    @DisplayName("Test successful calls in CLOSED state")
    void testSuccessfulCalls() throws Exception {
        String result = circuitBreaker.call(() -> "success");
        assertEquals("success", result);

  }

  /**
   * Precondition tester for {@code Iterator.remove()} that throws an exception with a consistent
   * error message.
   */
  static void checkRemove(boolean canRemove) {
    checkState(canRemove, "no calls to next() since the last call to remove()");
  }

  private CollectPreconditions() {}

   * listeners are added before any of the managed services are {@linkplain Service#startAsync
   * started}.
   *
   * <p>{@code addListener} guarantees execution ordering across calls to a given listener but not
   * across calls to multiple listeners. Specifically, a given listener will have its callbacks
   * invoked in the same order as the underlying service enters those states. Additionally, at most

  }

  @CollectionSize.Require(SEVERAL)
  @MapFeature.Require(SUPPORTS_REMOVE)
  /*
   * SetMultimap.asMap essentially returns a Map<K, Set<V>>; we just can't declare it that way.
   * Thus, calls like asMap().values().remove(someSet) are safe because they are comparing a set to
   * a collection of other sets.
   */
  @SuppressWarnings("CollectionUndefinedEquality")
  public void testValuesRemove() {

 * target iterators on demand. It also requires three additional constructor parameters: {@code
 * elementsToInsert}, the elements to be passed to {@code set()} and {@code add()} calls; {@code
 * features}, the features supported by the iterator; and {@code expectedElements}, the elements the
 * iterator should return in order.
 *

 *
 * <p>An instance may be called concurrently by multiple threads to process different entries.
 * Implementations of this interface should avoid performing blocking calls or synchronizing on
 * shared resources.
 *
 * @param <K> the most general type of keys this listener can listen for; for example {@code Object}
 *     if any key is acceptable