Storage.js

/**
 * The {@codelink Storage} is an unordered collection of named values of any
 * type. Values in the storage are named using {@code string} keys. The storage
 * can be therefore thought of as a {@code Map<string, *>}.
 *
 * @interface
 */
export default class Storage {
  /**
   * This method is used to finalize the initialization of the storage after
   * the dependencies provided through the constructor have been prepared for
   * use.
   *
   * This method must be invoked only once and it must be the first method
   * invoked on this instance.
   *
   * @return {Storage} This storage.
   */
  init() {}

  /**
   * Returns {@code true} if the entry identified by the specified key exists
   * in this storage.
   *
   * @param {string} key The key identifying the storage entry.
   * @return {boolean} {@code true} if the storage entry exists.
   */
  has() {}

  /**
   * Retrieves the value of the entry identified by the specified . The
   * method returns {@code undefined} if the entry does not exists.
   *
   * Entries set to the {@code undefined} value can be tested for existence
   * using the {@codelink has} method.
   *
   * @param {string} key The key identifying the storage entry.
   * @return {*} The value of the storage entry.
   */
  get() {}

  /**
   * Sets the storage entry identified by the specified key to the provided
   * value. The method creates the entry if it does not exist already.
   *
   * @param {string} key The key identifying the storage entry.
   * @param {*} value The storage entry value.
   * @return {Storage} This storage.
   */
  set() {}

  /**
   * Deletes the entry identified by the specified key from this storage.
   *
   * @param {string} key The key identifying the storage entry.
   * @return {Storage} This storage.
   */
  delete() {}

  /**
   * Clears the storage of all entries.
   *
   * @return {Storage} This storage.
   */
  clear() {}

  /**
   * Returns an iterator for traversing the keys in this storage. The order
   * in which the keys are traversed is undefined.
   *
   * @return {Iterator<string>} An iterator for traversing the keys in this
   *         storage. The iterator also implements the iterable protocol,
   *         returning itself as its own iterator, allowing it to be used in
   *         a {@code for..of} loop.
   */
  keys() {}

  /**
   * Returns the number of entries in this storage.
   *
   * @return {number} The number of entries in this storage.
   */
  size() {}
}