/**
     * Creates and returns a new instance of {@link Hashtable}.
     *
     * @param <K> the key type of {@link Hashtable}
     * @param <V> the value type of {@link Hashtable}
     * @return a new instance of {@link Hashtable}
     * @see Hashtable#Hashtable()
     */
    public static <K, V> Hashtable<K, V> newHashtable() {
        return new Hashtable<>();
    }

    /**

     * @return The environment for LDAP connection.
     */
    protected Hashtable<String, String> createEnvironment(final String initialContextFactory, final String securityAuthentication,
            final String providerUrl, final String principal, final String credntials) {
        final Hashtable<String, String> env = new Hashtable<>();
        putEnv(env, Context.INITIAL_CONTEXT_FACTORY, initialContextFactory);

   * value, you should always choose it explicitly.
   *
   * <p>The current implementation uses the concurrency level to create a fixed number of hashtable
   * segments, each governed by its own write lock. The segment lock is taken once for each explicit
   * write, and twice for each cache loading computation (once prior to loading the new value, and