OptionValue     string
}

// Table return the table name of the index.
func (idx Index) Table() string {
	return idx.TableName
}

// Name return the name of the index.
func (idx Index) Name() string {
	return idx.NameValue
}

// Columns return the columns of the index
func (idx Index) Columns() []string {
	return idx.ColumnList
}

// PrimaryKey returns the index is primary key or not.

   *
   * @since 16.0
   */
  public int remainingCapacity() {
    return maxSize - size();
  }

  @Override
  protected Queue<E> delegate() {
    return delegate;
  }

  /**
   * Adds the given element to this queue. If the queue is currently full, the element at the head
   * of the queue is evicted to make room.
   *
   * @return {@code true} always
   */
  @Override
  @CanIgnoreReturnValue

        if (nextSnapshot != null) return true

        synchronized(this@DiskLruCache) {
          // If the cache is closed, truncate the iterator.
          if (closed) return false

          while (delegate.hasNext()) {
            nextSnapshot = delegate.next()?.snapshot() ?: continue
            return true
          }
        }

        return false
      }

 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},
 *       typically because the type forbids nullable type arguments: For example, {@code
 *       ImmutableList.get} returns {@code E}, but that value is never {@code null}. (Accordingly,
 *       {@code ImmutableList} is declared to forbid {@code ImmutableList<@Nullable String>}.)

        }
        if (targetClassLoader != null) {
            return targetClassLoader;
        }
        if (thisClassLoader != null) {
            return thisClassLoader;
        }

        final ClassLoader systemClassLoader = ClassLoader.getSystemClassLoader();
        if (systemClassLoader != null) {
            return systemClassLoader;
        }