[bmcginnis]

I'm trying to pass variables picked up in lua over to a java program but don't know where to start. LuaJava has a poorly documented API and I've guess and checked everything I can think of. Is anyone familiar with LuaJava that could tell me how to this, I feel like it should be a no brainer. Thanks.

[bmcginnis]

Still can't figure it out. Heres my code so far:

import java.awt.AWTException;
import org.keplerproject.luajava.*;

public class Dinger
{
	private static _Dinger Dinger;

	public static void main(String[] args) throws AWTException
	{
		Dinger = new _Dinger();		
		
		Dinger.Delay(1);
		
		LuaState LuaState = LuaStateFactory.newLuaState();
		
		LuaState.openLibs();
	
	 	LuaState.LdoFile("Dinger.lua");
		
		double i = LuaState.getNumber(cursorX); // one of the many ideas I've tried, but doesn't work
		
		System.out.println(i);

	}
}

This program successfully runs and prints the word "Test" with the double i line removed.

and here is Dinger.lua:

print("Test")
local cursorX = 5

One thing I did figure out though is that luajava's LdoFile(""); has some limitations.

For example:

LuaState.LdoFile("Dinger.lua"); works --- when .lua in same folder as program
LuaState.LdoFile("lua/Dinger.lua"); works --- when .lua is in a sub-folder of the program
LuaState.LdoFile("C:/Users/Public/Games/World of Warcraft/Interface/Addons/Dinger.lua"); -- doesnt work -- for locations of file unless in sub-folder

Basically the only thing I want to know how to do is get the value of cursorX in Dinger.lua to the double i in Dinger.java

This post has been edited by bmcginnis: 20 October 2009 - 03:54 AM

[nick2price]

Unless someone is familiar with LuaJava, it would be impossible to tell you unless you post what you feel is the appropiate method to do this from the api.

[bmcginnis]

unfortunatly the api is hardly documented, with most the methods having nothing more than just the method name and i cant figure out how to pass a variable, if anyone has ideas that might work it would be appreciated

This post has been edited by bmcginnis: 20 October 2009 - 08:03 AM

[KYA]

I'll look into it as I'm sure the LuaJava library is similar to the C API for Lua. Check this out, it might point you in the right direction. Scroll down for the C API functions.

[KYA]

In C, I would do this:

#include <cstdio>
#include <cstring>

#ifdef __cplusplus
extern "C" {
#endif
#include <lua.h>
#include <lauxlib.h>
#include <lualib.h>
#ifdef __cplusplus
}
#endif

int main()
{
	char buff[256];
	int error;
	lua_State *L = luaL_newstate();			/*open a new lua state*/
	luaL_openlibs(L);						/*open standard libraries*/

	luaL_dofile(L, "test.lua");
	lua_getglobal(L, "xCursor");
	printf("%d\n\n", lua_tointeger(L,lua_gettop(L)));
	lua_close(L); /*clean up*/
	return 0;
}

test.lua is:

Quote

xCursor = 5

Output:

Quote

5

Basically is gets the global value, pushes it onto the stack. We then retrieve it (it's at index 1 of the stack, Lua does indexes differently).

[KYA]

Here's how I did it in java:

public static void main(String[] args){
		LuaState L = LuaStateFactory.newLuaState();
		L.LdoFile("test.lua");
		L.getGlobal("xCursor");
		System.out.println("xCursor's value is:" + L.toInteger(L.getTop()));
	}

I was getting zero, but that was due to the lua file not being in the right directory lol.

[bmcginnis]

That example looks promising as the API is fairly similar. The problem where I can't seem to find the similarity is here:

lua_getglobal(L, "xCursor"); // from your C code.

L.getGlobal("cursorX"); // Java code, getGlobal only has 1 arg which is a string since it realizes the luastate from L. infront.



converted code as best I could (not working though):

	LuaState L = LuaStateFactory.newLuaState();
		
	L.openLibs();
	
	 L.LdoFile("Dinger.lua");
		
	L.getGlobal("cursorX");
	
	int i = L.toNumber();
		
	System.out.println(i);

By the way toNumber requires int idx as an arg, would this have to do with the push index?

[bmcginnis]

just refreshed and realized u had posted a response before mine. It worked well thanks for the help.