/**
 * A volatile storage for objects based on a key, which may be invalidated and discarded.
 */
classCache{
  ...
}

/**
 * Splits a string on whitespace.  Repeated whitespace characters are collapsed.
 *
 *@param s The string to split.  An {@code null} string is treated as an empty string.
 *@return A list of the whitespace-delimited parts of the input.
 */
Listsplit(String s);

classTwitterDatabaseimplementsDatabase{
/**
   * Semantic version number.
   *
   *@return The database version in semver format.
   */
@Override
public StringgetVersion(){
    ...
  }
}