* </ul>
 *
 * <h2>Forwarding collections</h2>
 *
 * We provide implementations of collections that forward all method calls to a delegate collection
 * by default. Subclasses can override one or more methods to implement the decorator pattern. For
 * an example, see {@link ForwardingCollection}.
 *
 * <h2>Other</h2>
 *
 * <ul>
 *   <li>{@link EvictingQueue}
 *   <li>{@link Interner}, {@link Interners}

import java.util.concurrent.ExecutionException;

/**
 * This class provides a skeletal implementation of the {@code Cache} interface to minimize the
 * effort required to implement this interface.
 *
 * <p>To implement a cache, the programmer needs only to extend this class and provide an
 * implementation for the {@link #put} and {@link #getIfPresent} methods. {@link #getAllPresent} is

   * {@linkplain Object#equals equal} to the original, nor is it required to return even an object
   * of the same class. For example, if sublists of {@code MyList} instances were serializable,
   * those sublists might implement a private {@code MySubList} type but serialize as a plain {@code
   * MyList} to save space. So long as {@code MyList} has all the public supertypes of {@code

    // load timeout multiplier.  Or we could try to use a CPU time bound instead of wall clock time
    // bound.  But these ideas are harder to implement.  We do not try to detect or handle a
    // user-specified -XX:+DisableExplicitGC.
    //
    // TODO(user): Consider using
    // java/lang/management/OperatingSystemMXBean.html#getSystemLoadAverage()
    //

// DialContextWithLookupHost is a helper function which returns `net.DialContext` function.
// It randomly fetches an IP via custom LookupHost function and dials it by the given dial
// function. LookupHost may implement an internal DNS caching implementation, lookupHost
// input if nil then net.DefaultResolver.LookupHost is used.
//
// It dials one by one and returns first connected `net.Conn`.

- To be able to reliably use S3 multipart APIs feature of the SDKs without re-inventing the wheel of pre-signing the each URL in multipart API. This is very tedious to implement with all the scenarios of fault tolerance that's already implemented by the client SDK. The general client SDKs don't support multipart with presigned URLs.

      short i = 0;
      for (Object e : elements) {
        array[i++] = (Short) e;
      }
      return create(array);
    }

    /**
     * Creates a new collection containing the given elements; implement this method instead of
     * {@link #create(Object...)}.
     */
    protected abstract List<Short> create(Short[] elements);

    @Override
    public Short[] createArray(int length) {

      int i = 0;
      for (Object e : elements) {
        array[i++] = (Character) e;
      }
      return create(array);
    }

    /**
     * Creates a new collection containing the given elements; implement this method instead of
     * {@link #create(Object...)}.
     */
    protected abstract List<Character> create(Character[] elements);

    @Override
    public Character[] createArray(int length) {

      short i = 0;
      for (Object e : elements) {
        array[i++] = (Short) e;
      }
      return create(array);
    }

    /**
     * Creates a new collection containing the given elements; implement this method instead of
     * {@link #create(Object...)}.
     */
    protected abstract List<Short> create(Short[] elements);

    @Override
    public Short[] createArray(int length) {

      int i = 0;
      for (Object e : elements) {
        array[i++] = (Long) e;
      }
      return create(array);
    }

    /**
     * Creates a new collection containing the given elements; implement this method instead of
     * {@link #create(Object...)}.
     */
    protected abstract List<Long> create(Long[] elements);

    @Override
    public Long[] createArray(int length) {