ANN: Lua OS 0.6

[Stefan Reich <stefan.reich.maker.of.eye@...>]

Hey folks.

A new release! This is really beginning to be fun. You can now write
actual Swing-based GUI apps in (Safe) Lua.

Here goes:
http://luaos.net/luaos-0.6.php (for Windows + Ubuntu as per usual)

As an appetizer, check out this little script:

-- Show the Lua OS example scripts in a list
-- and allow user to run any of them
-- Uses a Java Swing GUI!

gui = safecomm.invoke{'gui', 'getMasterObject' }
frame = gui:showFrame('Lua OS example scripts. This is a Lua app!!')

-- Notice how we seamlessly create Java objects and call Java methods:

list = gui:newList()
vector = gui:newVector()
scripts = gui:getExampleScripts()
size = scripts:size()
for i = 0, size-1 do
  vector:add(scripts:getName(i))
end
list:setListData(vector)

btnRun = gui:newButton('Run example')

-- We can even do callbacks (call Lua objects from Java):

actionListener = object()
function actionListener:run()
  local idx = list:getSelectedIndex()
  if idx >= 0 then
    scripts:runScript(idx)
  end
end
btnRun:addActionListener(gui:actionListener(actionListener))

buttons = gui:newPanel()
buttons:setLayout(gui:stalactiteLayout())
buttons:add(btnRun)

-- This is a very nice and useful little layout manager I once made

layout = gui:letterLayout('LLB')
layout:setBorder(10)
frame:setLayout(layout)
frame:add('L', gui:newScrollPane(list))
frame:add('B', buttons)

-- Stay alive while user does things
safecomm.daemon()

...and that's all already. :)

I did some timing measurements and we get about 1 ms per roundtrip -
that includes socket transfer to Java, going to the Swing thread,
transferring stuff back to Lua and tunnelling sandbox barriers. Pretty
decent I'd say and certainly quick enough for now.

A note on security: The sandboxes are probably not tight at this point
as the comm infrastructure has not been audited. But the goal now is
to get stuff to actually work - super-security will come at a later
time.

Enjoy!
Stefan