* exists but cannot be used for another exchange, it is closed and this returns null.
   */
  private fun planReuseCallConnection(): ReusePlan? {
    // This may be mutated by releaseConnectionNoEvents()!
    val candidate = call.connection ?: return null

    // Make sure this connection is healthy & eligible for new exchanges. If it's no longer needed
    // then we're on the hook to close it.

import org.jspecify.annotations.Nullable;

/**
 * A {@link Closeable} that collects {@code Closeable} resources and closes them all when it is
 * {@linkplain #close closed}. This was intended to approximately emulate the behavior of Java 7's
 * <a href="http://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html"
 * >try-with-resources</a> statement in JDK6-compatible code. Code using this should be

        when(mockFuture.actionGet(anyLong(), any(TimeUnit.class))).thenAnswer(invocation -> {
            int count = attemptCount.incrementAndGet();
            if (count <= 5) {
                throw new RuntimeException("Simulated failure #" + count);
            }
            return "Success";
        });

        final String result = fesenClient.get(c -> mockFuture);

        assertEquals("Success", result);

  public final boolean trySetAccessible() {
    // We can't call accessibleObject.trySetAccessible since that was added in Java 9 and this code
    // should work on Java 8. So we emulate it this way.
    try {
      accessibleObject.setAccessible(true);
      return true;
    } catch (Exception e) { // sneaky checked exception
      return false;
    }
  }

     */
    public ImmutableIntArray build() {
      return count == 0 ? EMPTY : new ImmutableIntArray(array, 0, count);
    }
  }

  // Instance stuff here

  // The array is never mutated after storing in this field and the construction strategies ensure
  // it doesn't escape this class
  @SuppressWarnings("Immutable")
  private final int[] array;

  /*

     */
    public ImmutableLongArray build() {
      return count == 0 ? EMPTY : new ImmutableLongArray(array, 0, count);
    }
  }

  // Instance stuff here

  // The array is never mutated after storing in this field and the construction strategies ensure
  // it doesn't escape this class
  @SuppressWarnings("Immutable")
  private final long[] array;

  /*

      return new LockFreeBitArray(toPlainArray(data));
    }

    /**
     * Combines the two BitArrays using bitwise OR.
     *
     * <p>NOTE: Because of the use of atomics, if the other LockFreeBitArray is being mutated while
     * this operation is executing, not all of those new 1's may be set in the final state of this
     * LockFreeBitArray. The ONLY guarantee provided is that all the bits that were set in the other

   * Returns a view of the given character sequence as a {@link CharSource}. The behavior of the
   * returned {@code CharSource} and any {@code Reader} instances created by it is unspecified if
   * the {@code charSequence} is mutated while it is being read, so don't do that.
   *
   * @since 15.0 (since 14.0 as {@code CharStreams.asCharSource(String)})
   */
  public static CharSource wrap(CharSequence charSequence) {

   * Returns a view of the given character sequence as a {@link CharSource}. The behavior of the
   * returned {@code CharSource} and any {@code Reader} instances created by it is unspecified if
   * the {@code charSequence} is mutated while it is being read, so don't do that.
   *
   * @since 15.0 (since 14.0 as {@code CharStreams.asCharSource(String)})
   */
  public static CharSource wrap(CharSequence charSequence) {

   *
   * <p>For example, verify that calls to remove() actually removed the correct elements.
   *
   * @param elements the expected elements passed to the constructor, as mutated by {@code
   *     remove()}, {@code set()}, and {@code add()} calls
   */
  protected void verify(List<E> elements) {}

  /** Executes the test. */