How can I embed Lua in Java?

Try also kahlua and Mochalua.

There is http://www.keplerproject.org/luajava/manual.html, but essentially lua is more suitable for integration with C. There are a bunch of other scripting languages with good java integration around though. Consider groovy, jruby or jython for starters.

Lua is a C library, you can embed it in Java but you'll have to interface the java virtual machine and Lua with some C code.

The LuaJava authors have already done that work - you're better off using that than writing your own.