import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * A skeleton {@code Multimap} implementation, not necessarily in terms of a {@code Map}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
abstract class AbstractMultimap<K extends @Nullable Object, V extends @Nullable Object>
    implements Multimap<K, V> {
  @Override

const crossDomainXMLEntity = "/crossdomain.xml"

// A cross-domain policy file is an XML document that grants a web client, such as Adobe Flash Player
// or Adobe Acrobat (though not necessarily limited to these), permission to handle data across domains.
// When clients request content hosted on a particular source domain and that content make requests

     * The Java tools location is {@link StandardLocation#CLASS_PATH}.
     *
     * <h4>Context-sensitive interpretation</h4>
     * A dependency with this path type will not necessarily be placed on the class path.
     * There are two circumstances where the dependency may nevertheless be placed somewhere else:
     *
     * <ul>

    val name = this.withLock { nextQueueName++ }
    return TaskQueue(this, "Q$name")
  }

  /**
   * Returns a snapshot of queues that currently have tasks scheduled. The task runner does not
   * necessarily track queues that have no tasks scheduled.
   */
  fun activeQueues(): List<TaskQueue> {
    this.withLock {
      return busyQueues + readyQueues
    }
  }

  fun cancelAll() {
    assertLockHeld()

/// warning

This is a more or less advanced section. If you are just starting, you can skip it.

You don't necessarily need OAuth2 scopes, and you can handle authentication and authorization however you want.

But OAuth2 with scopes can be nicely integrated into your API (with OpenAPI) and your API docs.

  /**
   * End of Transmission Block: A communication control character used to indicate the end of a
   * block of data for communication purposes. ETB is used for blocking data where the block
   * structure is not necessarily related to the processing format.
   *
   * @since 8.0
   */
  public static final byte ETB = 23;

  /**
   * Cancel: A control character used to indicate that the data with which it is sent is in error or

   * The order of the elements in the element set is unspecified.
   *
   * <p>If the element set supports any removal operations, these necessarily cause <b>all</b>
   * occurrences of the removed element(s) to be removed from the multiset. Implementations are not
   * expected to support the add operations, although this is possible.
   *

  /** Returns true if this adapter can read [header] in a choice. */
  fun matches(header: DerHeader): Boolean

  /**
   * Returns a value from this adapter.
   *
   * This must always return a value, though it doesn't necessarily need to consume data from
   * [reader]. For example, if the reader's peeked tag isn't readable by this adapter, it may return
   * a default value.
   *

   * obtain this map with the more specific generic type {@code Map<K, SortedSet<V>>}, call {@link
   * Multimaps#asMap(SortedSetMultimap)} instead. <b>However</b>, the returned map <i>itself</i> is
   * not necessarily a {@link SortedMap}: A {@code SortedSetMultimap} must expose the <i>values</i>
   * for a given key in sorted order, but it need not expose the <i>keys</i> in sorted order.

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