* #toMap(Iterable, Function)}.
   *
   * <p>Specifically, for each {@code k} in the backing set, the returned map has an entry mapping
   * {@code k} to {@code function.apply(k)}. The {@code keySet}, {@code values}, and {@code
   * entrySet} views of the returned map iterate in the same order as the backing set.
   *
   * <p>Modifications to the backing set are read through to the returned map. The returned map

import java.util.Set;
import org.jspecify.annotations.Nullable;

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

import java.util.Set;
import org.jspecify.annotations.Nullable;

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

   * backing map.
   *
   * <p>This instance will assume ownership of {@code countMap}, and other code should not maintain
   * references to the map or modify it in any way.
   *
   * <p>The returned multiset is serializable if the input map is.
   *
   * @param countMap backing map for storing the elements in the multiset and their counts. It must

import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * A multimap which forwards all its method calls to another multimap. Subclasses should override
 * one or more methods to modify the behavior of the backing multimap as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * A multimap which forwards all its method calls to another multimap. Subclasses should override
 * one or more methods to modify the behavior of the backing multimap as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

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>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingBlockingDeque} forward <b>indiscriminately</b>

   * java.util.TreeMap}).
   *
   * <p>Each method invocation on the set returned by this method results in exactly one method
   * invocation on the backing map or its {@code keySet} view, with one exception. The {@code
   * addAll} method is implemented as a sequence of {@code put} invocations on the backing map.
   *
   * <p>The specified map must be empty at the time this method is invoked, and should not be

import org.jspecify.annotations.Nullable;

/**
 * A concurrent map which forwards all its method calls to another concurrent map. Subclasses should
 * override one or more methods to modify the behavior of the backing map as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class forwards calls to <i>only some</i> {@code

   * #toMap(Iterable, Function)}.
   *
   * <p>Specifically, for each {@code k} in the backing set, the returned map has an entry mapping
   * {@code k} to {@code function.apply(k)}. The {@code keySet}, {@code values}, and {@code
   * entrySet} views of the returned map iterate in the same order as the backing set.
   *
   * <p>Modifications to the backing set are read through to the returned map. The returned map