org.luaj.vm2.lib
Class PackageLib

java.lang.Object
  org.luaj.vm2.Varargs
      org.luaj.vm2.LuaValue
          org.luaj.vm2.LuaFunction
              org.luaj.vm2.lib.LibFunction
                  org.luaj.vm2.lib.TwoArgFunction
                      org.luaj.vm2.lib.PackageLib

public class PackageLib
extends TwoArgFunction

Subclass of LibFunction which implements the lua standard package and module library functions.

Lua Environment Variables

The following variables are available to lua scrips when this library has been loaded:

• "package.loaded" Lua table of loaded modules.
• "package.path" Search path for lua scripts.
• "package.preload" Lua table of uninitialized preload functions.
• "package.searchers" Lua table of functions that search for object to load.

Java Environment Variables

These Java environment variables affect the library behavior:

• "luaj.package.path" Initial value for "package.path". Default value is "?.lua"

Loading

Typically, this library is included as part of a call to either JsePlatform.standardGlobals() or JmePlatform.standardGlobals()

 Globals globals = JsePlatform.standardGlobals();
 System.out.println( globals.get("require").call"foo") );
  

To instantiate and use it directly, link it into your globals table via LuaValue.load(LuaValue) using code such as:

 Globals globals = new Globals();
 globals.load(new JseBaseLib());
 globals.load(new PackageLib());
 System.out.println( globals.get("require").call("foo") );
  

Limitations

This library has been implemented to match as closely as possible the behavior in the corresponding library in C. However, the default filesystem search semantics are different and delegated to the bas library as outlined in the BaseLib and JseBaseLib documentation.

See Also:

LibFunction, BaseLib, JseBaseLib, JsePlatform, JmePlatform, Lua 5.2 Package Lib Reference

Nested Class Summary

class	PackageLib.java_searcher
static class	PackageLib.loadlib
class	PackageLib.lua_searcher
class	PackageLib.preload_searcher
class	PackageLib.require require (modname) Loads the given module.
class	PackageLib.searchpath

Field Summary

static java.lang.String	DEFAULT_LUA_PATH The default value to use for package.path.
PackageLib.java_searcher	java_searcher Loader that loads as a Java class.
PackageLib.lua_searcher	lua_searcher Loader that loads as a lua script using the lua path currently in PackageLib.searchpath
PackageLib.preload_searcher	preload_searcher Loader that loads from preload table if found there

Fields inherited from class org.luaj.vm2.lib.LibFunction

name, opcode

Fields inherited from class org.luaj.vm2.LuaFunction

s_metatable

Fields inherited from class org.luaj.vm2.LuaValue

ADD, CALL, CONCAT, DIV, EMPTYSTRING, ENV, EQ, FALSE, INDEX, LE, LEN, LT, METATABLE, MINUSONE, MOD, MODE, MUL, NEWINDEX, NIL, NILS, NONE, NOVALS, ONE, POW, SUB, TBOOLEAN, TFUNCTION, TINT, TLIGHTUSERDATA, TNIL, TNONE, TNUMBER, TOSTRING, TRUE, TSTRING, TTABLE, TTHREAD, TUSERDATA, TVALUE, TYPE_NAMES, UNM, ZERO

Constructor Summary

PackageLib()

Method Summary

LuaValue	call(LuaValue modname, LuaValue env) Perform one-time initialization on the library by adding package functions to the supplied environment, and returning it as the return value.
void	setIsLoaded(java.lang.String name, LuaTable value) Allow packages to mark themselves as loaded
void	setLuaPath(java.lang.String newLuaPath) Set the lua path used by this library instance to a new value.
static java.lang.String	toClassname(java.lang.String filename) Convert lua filename to valid class name
java.lang.String	tojstring() Convert to human readable String for any type.

Methods inherited from class org.luaj.vm2.lib.TwoArgFunction

call, call, call, invoke

Methods inherited from class org.luaj.vm2.lib.LibFunction

bind, bind, call, newupe, newupl, newupn

Methods inherited from class org.luaj.vm2.LuaFunction

checkfunction, classnamestub, getmetatable, isfunction, name, optfunction, strvalue, type, typename

Methods inherited from class org.luaj.vm2.LuaValue

add, add, add, and, arg, arg1, argerror, argerror, aritherror, aritherror, arithmt, arithmtwith, assert_, buffer, call, callmt, checkboolean, checkclosure, checkdouble, checkglobals, checkint, checkinteger, checkjstring, checklong, checkmetatag, checknotnil, checknumber, checknumber, checkstring, checktable, checkthread, checkuserdata, checkuserdata, compareerror, compareerror, comparemt, concat, concat, concatmt, concatTo, concatTo, concatTo, div, div, div, divInto, eq_b, eq, eqmtcall, equals, error, get, get, get, gettable, gt_b, gt_b, gt_b, gt, gt, gt, gteq_b, gteq_b, gteq_b, gteq, gteq, gteq, illegal, inext, initupvalue1, invoke, invoke, invoke, invoke, invoke, invokemethod, invokemethod, invokemethod, invokemethod, invokemethod, invokemethod, isboolean, isclosure, isint, isinttype, islong, isnil, isnumber, isstring, istable, isthread, isuserdata, isuserdata, isvalidkey, len, lenerror, length, listOf, listOf, load, lt_b, lt_b, lt_b, lt, lt, lt, lteq_b, lteq_b, lteq_b, lteq, lteq, lteq, metatableOf, metatag, method, method, method, method, method, method, mod, mod, mod, modFrom, mul, mul, mul, narg, neg, neq_b, neq, next, not, onInvoke, optboolean, optclosure, optdouble, optint, optinteger, optjstring, optlong, optnumber, optstring, opttable, optthread, optuserdata, optuserdata, optvalue, or, pow, pow, pow, powWith, powWith, presize, raweq, raweq, raweq, raweq, raweq, rawget, rawget, rawget, rawlen, rawset, rawset, rawset, rawset, rawset, rawset, rawset, rawsetlist, set, set, set, set, set, set, set, setmetatable, settable, strcmp, strcmp, strongvalue, sub, sub, sub, subargs, subFrom, subFrom, tableOf, tableOf, tableOf, tableOf, tableOf, tableOf, tailcallOf, testfor_b, toboolean, tobyte, tochar, todouble, tofloat, toint, tolong, tonumber, toshort, tostring, toString, touserdata, touserdata, typerror, unimplemented, userdataOf, userdataOf, valueOf, valueOf, valueOf, valueOf, valueOf, valueOf, varargsOf, varargsOf, varargsOf, varargsOf, varargsOf, varargsOf

Methods inherited from class org.luaj.vm2.Varargs

argcheck, checkboolean, checkclosure, checkdouble, checkfunction, checkint, checkinteger, checkjstring, checklong, checknotnil, checknumber, checkstring, checktable, checkthread, checkuserdata, checkuserdata, checkvalue, eval, isfunction, isnil, isnoneornil, isnumber, isstring, istable, isTailcall, isthread, isuserdata, isvalue, optboolean, optclosure, optdouble, optfunction, optint, optinteger, optjstring, optlong, optnumber, optstring, opttable, optthread, optuserdata, optuserdata, optvalue, toboolean, tobyte, tochar, todouble, tofloat, toint, tojstring, tolong, toshort, touserdata, touserdata, type

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

DEFAULT_LUA_PATH

public static java.lang.String DEFAULT_LUA_PATH

The default value to use for package.path. This can be set with the system property "luaj.package.path", and is "?.lua" by default.

preload_searcher

public PackageLib.preload_searcher preload_searcher

Loader that loads from preload table if found there

lua_searcher

public PackageLib.lua_searcher lua_searcher

Loader that loads as a lua script using the lua path currently in PackageLib.searchpath

java_searcher

public PackageLib.java_searcher java_searcher

Loader that loads as a Java class. Class must have public constructor and be a LuaValue.

Constructor Detail

PackageLib

public PackageLib()

Method Detail

call

public LuaValue call(LuaValue modname,
                     LuaValue env)

Perform one-time initialization on the library by adding package functions to the supplied environment, and returning it as the return value. It also creates the package.preload and package.loaded tables for use by other libraries.

Specified by:

call in class TwoArgFunction

Parameters:

modname - the module name supplied if this is loaded via 'require'.

env - the environment to load into, typically a Globals instance.

Returns:

First return value (this(arg1,arg2)), or LuaValue.NIL if there were none.

See Also:

LuaValue.call(), LuaValue.call(LuaValue), LuaValue.call(LuaValue, LuaValue, LuaValue), LuaValue.invoke(LuaValue, Varargs), LuaValue.method(String,LuaValue,LuaValue), LuaValue.method(LuaValue,LuaValue,LuaValue)

setIsLoaded

public void setIsLoaded(java.lang.String name,
                        LuaTable value)

Allow packages to mark themselves as loaded

setLuaPath

public void setLuaPath(java.lang.String newLuaPath)

Set the lua path used by this library instance to a new value. Merely sets the value of PackageLib.searchpath to be used in subsequent searches.

tojstring

public java.lang.String tojstring()

Description copied from class: LuaValue

Convert to human readable String for any type.

Overrides:

tojstring in class LibFunction

Returns:

String for use by human readers based on type.

See Also:

LuaValue.tostring(), LuaValue.optjstring(String), LuaValue.checkjstring(), LuaValue.isstring(), LuaValue.TSTRING

toClassname

public static final java.lang.String toClassname(java.lang.String filename)

Convert lua filename to valid class name