scala-newline-and-indent.el

(require 'scala-mode-auto nil t)

(defun iy/scala-newline-and-indent ()
  (interactive)
  (when (and (looking-back "{ *") (looking-at " *}")) ;; open empty braces
    (delete-horizontal-space)
    (scala-newline)
    (scala-indent-line-to (scala-indentation))
    (forward-line -1)
    (end-of-line))
  (scala-newline)
  (scala-indent-line-to (scala-indentation)))

(defun iy/scala-mode-init ()
  (local-set-key (kbd "<return>") 'iy/scala-newline-and-indent)
  (local-set-key (kbd "C-<return>") 'scala-newline)
  (if (fboundp 'c-subword-mode)
      (c-subword-mode t)
    (subword-mode t))
  (scala-electric-mode))

(add-hook 'scala-mode-hook 'iy/scala-mode-init)