* emacs lisp code block

#+begin_src emacs-lisp :var tbl='()
  (defun all-to-string (tbl)
    (if (listp tbl)
        (mapcar #'all-to-string tbl)
      (if (stringp tbl)
          tbl
        (format "%s" tbl))))
  (all-to-string tbl)
#+end_src


* java code block
  
#+begin_src java :classname myfirstjavaprog
  class myfirstjavaprog
  {  
      public static void main(String args[])
      {
          System.out.println("Hello World!");
      }
  }
#+end_src

#+begin_src C++
class myfirstjavaprog
  {
    public static void main(String args[])
    {
      System.out.println("Hello World!");
    }
  }
#+end_src