*         .addAll(WEBSAFE_COLORS)
   *         .add(new Color(0, 191, 255))
   *         .build();
   * }</pre>
   *
   * <p>Elements appear in the resulting list in the same order they were added to the builder.
   *
   * <p>Builder instances can be reused; it is safe to call {@link #build} multiple times to build
   * multiple lists in series. Each new list contains all the elements of the ones created before
   * it.

   *         .addAll(WEBSAFE_COLORS)
   *         .add(new Color(0, 191, 255))
   *         .build();
   * }</pre>
   *
   * <p>Elements appear in the resulting list in the same order they were added to the builder.
   *
   * <p>Builder instances can be reused; it is safe to call {@link #build} multiple times to build
   * multiple lists in series. Each new list contains all the elements of the ones created before
   * it.

    Builder<E> combine(Builder<E> builder) {
      checkNotNull(builder);
      contents.addAll(builder.contents);
      return this;
    }

    @Override
    public ImmutableList<E> build() {
      return copyOf(contents);
    }
  }