[Fix] Fix LuaName being ignored for fields passed to the Lua engine

* Also added a test to verfiy it working and updated some other tests
* Improved LuaValue support for values returned from lua function calls

GILua/build.gradle.kts

@@ -26,6 +26,9 @@ dependencies {
     compileOnly(libs.jvm.lombok)
     annotationProcessor(libs.jvm.lombok)
     implementation(libs.jvm.rtree.multi)
+    testImplementation(project(":base"))
+    testImplementation(project(":LuaJEngine"))
+    testImplementation(project(":JNLuaEngine"))
 }
 tasks.withType<KotlinCompile>().configureEach {
     compilerOptions {

GILua/src/test/java/org/anime_game_servers/gi_lua/test/models/ScriptArgsTest.kt

@@ -0,0 +1,150 @@
+package org.anime_game_servers.gi_lua.test.models
+
+import kotlinx.io.Source
+import org.anime_game_servers.core.base.annotations.lua.LuaStatic
+import org.anime_game_servers.gi_lua.models.ScriptArgs
+import org.anime_game_servers.gi_lua.models.loader.GIScriptLoader
+import org.anime_game_servers.jnlua_engine.JNLuaEngine
+import org.anime_game_servers.lua.engine.*
+import org.anime_game_servers.lua.models.ScriptType
+import org.anime_game_servers.lua.utils.asSource
+import org.anime_game_servers.luaj_engine.LuaJEngine
+import org.junit.jupiter.api.Test
+import java.nio.file.Files
+import java.nio.file.Path
+
+data class LuaContext(val engine: LuaEngine)
+
+@LuaStatic
+object KotlinFunctions{
+    @JvmStatic
+    fun checkScriptArgs(context:LuaContext, luaTable:Any) : Any{
+        // retrieve the int array as lua table from the lua side
+        val table = context.engine.getTable(luaTable)
+        val array = table.getAsIntArray()
+        val result = context.engine.createTable()
+
+        assert(array.size == 5)
+        array.forEachIndexed { index, value ->
+            assert(index+1 == value)
+            result.set(index, value)
+        }
+
+        // convert the int array back to a luaTable for lua and return it
+        return result.getRawTable()
+    }
+
+    @JvmStatic
+    fun getScriptArgs(context:LuaContext) : Any{
+        // retrieve the int array as lua table from the lua side
+        /*val table = context.engine.getTable(luaTable)
+        val x = table.optInt("x",0)
+        val y = table.optInt("y",0)
+        val z = table.optInt("z",0)*/
+
+        val result = context.engine.createTable()
+        /*result.set("x", x)
+        result.set("y", y)
+        result.set("z", z)*/
+
+        // convert the int array back to a luaTable for lua and return it
+        return result.getRawTable()
+    }
+}
+
+abstract class TestScriptLoader : GIScriptLoader {
+    abstract val engine: LuaEngine
+    override fun getScriptPath(scriptName: String): Path? {
+        val uri = ClassLoader.getSystemResource(scriptName).toURI()
+        return Path.of(uri)
+    }
+
+    override fun openScript(params: BaseScriptLoader.ScriptLoadParams): Source? {
+        val basePath: String = params.getBasePath()
+        val scriptPath = getScriptPath(basePath) ?: return null
+        if(Files.exists(scriptPath)){
+            return scriptPath.asSource()
+        }
+        return null
+    }
+
+    override fun getScript(scriptLoadParams: BaseScriptLoader.ScriptLoadParams): LuaScript? {
+        val basePath: String = scriptLoadParams.getBasePath()
+        val scriptPath = getScriptPath(basePath) ?: return null
+        return engine.getScript(scriptPath, scriptLoadParams.getScriptType());
+    }
+}
+
+class LuaJTest : ScriptArgsTest() {
+
+    override val scriptLoader = object : TestScriptLoader(){
+        override val engine: LuaEngine = LuaJEngine(ScriptConfig(this, RequireMode.DISABLED))
+    }
+
+    @Test
+    fun runTest(){
+        checkScriptArgs()
+    }
+}
+
+class JNLuaTest : ScriptArgsTest() {
+
+    override val scriptLoader = object : TestScriptLoader(){
+        override val engine: LuaEngine = JNLuaEngine(ScriptConfig(this, RequireMode.DISABLED))
+    }
+
+    @Test
+    fun runTest(){
+        checkScriptArgs()
+    }
+}
+
+abstract class ScriptArgsTest{
+    abstract val scriptLoader : TestScriptLoader
+
+    fun getEngine(): LuaEngine {
+        return scriptLoader.engine
+    }
+
+    fun checkScriptArgs() {
+        val engine = getEngine()
+        LuaEngine.registerNamespace(this::class.java.packageName)
+        engine.addGlobals()
+        val uri = ClassLoader.getSystemResource("ScriptArgsTest.lua").toURI()
+        val path = Path.of(uri);
+        val script = engine.getScript(path, ScriptType.EXECUTABLE)
+
+        assert(script != null)
+
+        script!!.evaluate()
+        val context = LuaContext(engine)
+        val args = ScriptArgs(7,8).apply {
+            param1 = 1
+            param2 = 2
+            param3 = 3
+            param4 = 4
+            sourceEid = 5
+            targetEid = 6
+            uid = 9
+            paramString1 = "paramString1"
+            source = "source"
+        }
+
+        assert(script.hasMethod("testScriptArgs"))
+        val luaValue = script.callMethod("testScriptArgs", context, args)!!
+        assert(luaValue.isTable())
+        val result = luaValue.asObject(ScriptArgs::class.java)
+        assert(result != null)
+        assert(result!!.param1 == args.param1)
+        assert(result.param2 == args.param2)
+        assert(result.param3 == args.param3)
+        assert(result.param4 == args.param4)
+        assert(result.sourceEid == args.sourceEid)
+        assert(result.targetEid == args.targetEid)
+        assert(result.groupId == args.groupId)
+        assert(result.uid == args.uid)
+        assert(result.type == args.type)
+        assert(result.paramString1 == args.paramString1)
+        assert(result.source == args.source)
+    }
+}

GILua/src/test/resources/ScriptArgsTest.lua

@@ -0,0 +1,39 @@
+
+function testScriptArgs(ctx, evt)
+    if(evt.param1 ~= 1) then
+        return -1
+    end
+    if(evt.param2 ~= 2) then
+        return -2
+    end
+    if(evt.param3 ~= 3) then
+        return -3
+    end
+    if(evt.param4 ~= 4) then
+        return -4
+    end
+    if(evt.source_eid ~= 5) then
+        return -5
+    end
+    if(evt.target_eid ~= 6) then
+        return -6
+    end
+    if(evt.group_id ~= 7) then
+        return -7
+    end
+    if(evt.type ~= 8) then
+        return -8
+    end
+    if(evt.uid ~= 9) then
+        return -9
+    end
+
+    if(evt.param_str1 ~= "paramString1") then
+        return -10
+    end
+    if(evt.source_name ~= "source") then
+        return -11
+    end
+
+    return evt
+end

JNLuaEngine/src/main/java/org/anime_game_servers/jnlua_engine/JNLuaReflector.java

@@ -0,0 +1,153 @@
+package org.anime_game_servers.jnlua_engine;
+
+import io.github.oshai.kotlinlogging.KLogger;
+import io.github.oshai.kotlinlogging.KotlinLogging;
+import lombok.Getter;
+import org.anime_game_servers.lua.utils.LuaHelpersJvmKt;
+import org.terasology.jnlua.*;
+
+import java.beans.BeanInfo;
+import java.beans.IntrospectionException;
+import java.beans.Introspector;
+import java.beans.PropertyDescriptor;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.util.*;
+
+public class JNLuaReflector extends DefaultJavaReflector {
+    private static KLogger logger = KotlinLogging.INSTANCE.logger(JNLuaReflector.class.getName());
+    @Getter
+    private static final JNLuaReflector INSTANCE = new JNLuaReflector();
+
+    @Override
+    protected Map<String, Accessor> createClassAccessors(Class<?> clazz) {
+        Map<String, Accessor> result = new HashMap<String, Accessor>();
+
+        // Fields
+        Field[] fields = clazz.getFields();
+        for (int i = 0; i < fields.length; i++) {
+            var field = fields[i];
+            var luaNames = LuaHelpersJvmKt.getLuaNames(field);
+            for (var luaName : luaNames) {
+                result.put(luaName, new FieldAccessor(field));
+            }
+        }
+
+        // Methods
+        Map<String, Map<List<Class<?>>, Invocable>> accessibleMethods = new HashMap<String, Map<List<Class<?>>, Invocable>>();
+        Method[] methods = clazz.getMethods();
+        for (int i = 0; i < methods.length; i++) {
+            // Do not overwrite fields
+            Method method = methods[i];
+            if (result.containsKey(method.getName())) {
+                continue;
+            }
+
+            // Attempt to find the method in a public class if the declaring
+            // class is not public
+            if (!Modifier.isPublic(method.getDeclaringClass().getModifiers())) {
+                method = getPublicClassMethod(clazz, method.getName(),
+                        method.getParameterTypes());
+                if (method == null) {
+                    continue;
+                }
+            }
+
+            // For each method name and parameter type list, keep
+            // only the method declared by the most specific class
+            Map<List<Class<?>>, Invocable> overloaded = accessibleMethods
+                    .get(method.getName());
+            if (overloaded == null) {
+                overloaded = new HashMap<List<Class<?>>, Invocable>();
+                accessibleMethods.put(method.getName(), overloaded);
+            }
+            List<Class<?>> parameterTypes = Arrays.asList(method
+                    .getParameterTypes());
+            Invocable currentInvocable = overloaded.get(parameterTypes);
+            if (currentInvocable != null
+                    && method.getDeclaringClass().isAssignableFrom(
+                    currentInvocable.getDeclaringClass())) {
+                continue;
+            }
+            overloaded.put(parameterTypes, new InvocableMethod(method));
+        }
+        for (Map.Entry<String, Map<List<Class<?>>, Invocable>> entry : accessibleMethods
+                .entrySet()) {
+            result.put(entry.getKey(), new InvocableAccessor(clazz, entry
+                    .getValue().values()));
+        }
+
+        // Constructors
+        Constructor<?>[] constructors = clazz.getConstructors();
+        List<Invocable> accessibleConstructors = new ArrayList<Invocable>(
+                constructors.length);
+        for (int i = 0; i < constructors.length; i++) {
+            // Ignore constructor if the declaring class is not public
+            if (!Modifier.isPublic(constructors[i].getDeclaringClass()
+                    .getModifiers())) {
+                continue;
+            }
+            accessibleConstructors
+                    .add(new InvocableConstructor(constructors[i]));
+        }
+        if (clazz.isInterface()) {
+            accessibleConstructors.add(new InvocableProxy(clazz));
+        }
+        if (!accessibleConstructors.isEmpty()) {
+            result.put("new", new InvocableAccessor(clazz,
+                    accessibleConstructors));
+        }
+
+        // Properties
+        BeanInfo beanInfo;
+        try {
+            beanInfo = Introspector.getBeanInfo(clazz);
+        } catch (IntrospectionException e) {
+            throw new RuntimeException(e);
+        }
+        PropertyDescriptor[] propertyDescriptors = beanInfo
+                .getPropertyDescriptors();
+        for (int i = 0; i < propertyDescriptors.length; i++) {
+            // Do not overwrite fields or methods
+            if (result.containsKey(propertyDescriptors[i].getName())) {
+                continue;
+            }
+
+            // Attempt to find the read/write methods in a public class if the
+            // declaring class is not public
+            Method method = propertyDescriptors[i].getReadMethod();
+            if (method != null
+                    && !Modifier.isPublic(method.getDeclaringClass()
+                    .getModifiers())) {
+                method = getPublicClassMethod(clazz, method.getName(),
+                        method.getParameterTypes());
+                try {
+                    propertyDescriptors[i].setReadMethod(method);
+                } catch (IntrospectionException e) {
+                }
+            }
+            method = propertyDescriptors[i].getWriteMethod();
+            if (method != null
+                    && !Modifier.isPublic(method.getDeclaringClass()
+                    .getModifiers())) {
+                method = getPublicClassMethod(clazz, method.getName(),
+                        method.getParameterTypes());
+                try {
+                    propertyDescriptors[i].setWriteMethod(method);
+                } catch (IntrospectionException e) {
+                }
+            }
+
+            // Do not process properties without a read and a write method
+            if (propertyDescriptors[i].getReadMethod() == null
+                    && propertyDescriptors[i].getWriteMethod() == null) {
+                continue;
+            }
+            result.put(propertyDescriptors[i].getName(), new PropertyAccessor(
+                    clazz, propertyDescriptors[i]));
+        }
+        return result;
+    }
+}

JNLuaEngine/src/main/java/org/anime_game_servers/jnlua_engine/JNLuaScript.java

@@ -8,10 +8,7 @@ import org.anime_game_servers.lua.engine.LuaEngine;
 import org.anime_game_servers.lua.engine.LuaScript;
 import org.anime_game_servers.lua.engine.LuaValue;
 import org.anime_game_servers.lua.engine.RequireMode;
-import org.anime_game_servers.lua.models.BooleanLuaValue;
+import org.anime_game_servers.lua.models.*;
-import org.anime_game_servers.lua.models.IntLuaValue;
-import org.anime_game_servers.lua.models.MutableBoolean;
-import org.anime_game_servers.lua.models.ScriptType;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.terasology.jnlua.script.CompiledLuaScript;
@@ -51,6 +48,7 @@ public class JNLuaScript implements LuaScript {
         context.setBindings(binding, ScriptContext.ENGINE_SCOPE);
         val luaState = binding.getLuaState();
         luaState.setConverter(JNLuaConverter.getINSTANCE());
+        luaState.setJavaReflector(JNLuaReflector.getINSTANCE());
 
         val requireFunction = JNLuaRequireCommonFunction.getInstance(engine.getScriptConfig());
         binding.put(requireFunction.getName(), requireFunction);
@@ -121,13 +119,11 @@ public class JNLuaScript implements LuaScript {
     @Override
     public LuaValue callMethod(@NotNull String methodName, Object... args) throws ScriptException, NoSuchMethodException {
         val result = ((Invocable) scriptEngine).invokeFunction(methodName, args);
-        if (result instanceof Boolean) {
+        if (result instanceof Boolean boolVal) {
-            return ((Boolean) result) ? BooleanLuaValue.TRUE : BooleanLuaValue.FALSE;
+            return boolVal ? BooleanLuaValue.TRUE : BooleanLuaValue.FALSE;
-        } else if (result instanceof Integer) {
-            return new IntLuaValue((Integer) result);
         }
-        //TODO
+
-        return null;
+        return new JNLuaValue(engine, result);
     }
 
     @Override

JNLuaEngine/src/main/java/org/anime_game_servers/jnlua_engine/JNLuaValue.kt

@@ -0,0 +1,104 @@
+package org.anime_game_servers.jnlua_engine
+
+import org.anime_game_servers.lua.engine.LuaValue
+
+class JNLuaValue internal constructor(private val engine: JNLuaEngine, private val value: Any?) : LuaValue {
+    override fun isNull(): Boolean {
+        return value == null
+    }
+
+    override fun isBoolean(): Boolean {
+        return value is Boolean
+    }
+
+    override fun isInteger(): Boolean {
+        return value is Int
+    }
+
+    override fun isLong(): Boolean {
+        return value is Long
+    }
+
+    override fun isDouble(): Boolean {
+        return value is Double
+    }
+
+    override fun isFloat(): Boolean {
+        return value is Float
+    }
+
+    override fun isString(): Boolean {
+        return value is String
+    }
+
+    override fun isTable(): Boolean {
+        return value is Map<*, *> || value is JNLuaTable || value is Collection<*> || value != null && value !is Number && value !is Boolean && value !is String
+    }
+
+    override fun asBoolean(): Boolean {
+        return when(value){
+            is Boolean -> value
+            is Number -> value.toInt() != 0
+            is String -> value.toBoolean()
+            else -> false
+        }
+    }
+
+    override fun asInteger(): Int {
+        return when(value){
+            is Number -> value.toInt()
+            is Boolean -> if(value) 1 else 0
+            is String -> value.toInt()
+            else -> 0
+        }
+    }
+
+    override fun asLong(): Long {
+        return when(value){
+            is Number -> value.toLong()
+            is Boolean -> if(value) 1L else 0L
+            is String -> value.toLong()
+            else -> 0L
+        }
+    }
+
+    override fun asDouble(): Double {
+        return when(value){
+            is Number -> value.toDouble()
+            is Boolean -> if(value) 1.0 else 0.0
+            is String -> value.toDouble()
+            else -> 0.0
+        }
+    }
+
+    override fun asFloat(): Float {
+        return when(value){
+            is Number -> value.toFloat()
+            is Boolean -> if(value) 1f else 0f
+            is String -> value.toFloat()
+            else -> 0f
+        }
+    }
+
+    override fun asString(): String? {
+        return when(value){
+            is String -> value
+            is Number -> value.toString()
+            is Boolean -> value.toString()
+            else -> null
+        }
+    }
+
+    override fun <T> asObject(type: Class<T>): T? {
+        if (value == null || !isTable()) {
+            return null
+        }
+
+        if(type.isAssignableFrom(value.javaClass)){
+            return value as T
+        }
+
+        // TODO expects LuaValueProxy
+        return engine.serializer.toObject(type, value)
+    }
+}

LuaJEngine/src/main/java/org/anime_game_servers/luaj_engine/LuaJEngine.kt

@@ -5,8 +5,8 @@ import kotlinx.io.asInputStream
 import kotlinx.io.buffered
 import org.anime_game_servers.lua.engine.*
 import org.anime_game_servers.lua.models.ScriptType
+import org.anime_game_servers.luaj_engine.coerse.CoerceJavaToLua
 import org.luaj.vm2.lib.ResourceFinder
-import org.luaj.vm2.lib.jse.CoerceJavaToLua
 import org.luaj.vm2.script.LuajContext
 import java.io.ByteArrayInputStream
 import java.io.IOException

LuaJEngine/src/main/java/org/anime_game_servers/luaj_engine/LuaJScript.java

@@ -3,7 +3,6 @@ package org.anime_game_servers.luaj_engine;
 import io.github.oshai.kotlinlogging.KLogger;
 import io.github.oshai.kotlinlogging.KotlinLogging;
 import kotlin.Pair;
-import kotlin.text.Regex;
 import lombok.val;
 import org.anime_game_servers.lua.engine.LuaEngine;
 import org.anime_game_servers.lua.engine.LuaScript;
@@ -12,7 +11,7 @@ import org.anime_game_servers.lua.engine.RequireMode;
 import org.anime_game_servers.lua.models.BooleanLuaValue;
 import org.anime_game_servers.lua.models.MutableBoolean;
 import org.anime_game_servers.lua.models.ScriptType;
-import org.luaj.vm2.lib.jse.CoerceJavaToLua;
+import org.anime_game_servers.luaj_engine.coerse.CoerceJavaToLua;
 
 import javax.annotation.Nonnull;
 import javax.script.Bindings;
@@ -24,7 +23,6 @@ import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.List;
 import java.util.Map;
-import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.regex.Pattern;
 
 public class LuaJScript implements LuaScript {

LuaJEngine/src/main/java/org/anime_game_servers/luaj_engine/LuaJValue.java

@@ -48,7 +48,7 @@ public class LuaJValue implements LuaValue {
 
     @Override
     public boolean isTable() {
-        return value.istable();
+        return value.istable() || value.isuserdata();
     }
 
     @Override
@@ -83,10 +83,14 @@ public class LuaJValue implements LuaValue {
 
     @Override
     public <T> T asObject(Class<T> type) {
-        if (!value.istable()) {
+        if (!value.istable() && !value.isuserdata()) {
             return null;
         }
 
+        if(value.isuserdata()) {
+            return (T) value.checkuserdata(type);
+        }
+
         return engine.getSerializer().toObject(type, value.checktable());
     }
 }

LuaJEngine/src/main/java/org/anime_game_servers/luaj_engine/coerse/CoerceJavaToLua.java

@@ -0,0 +1,170 @@
+package org.anime_game_servers.luaj_engine.coerse;
+
+import org.luaj.vm2.*;
+import org.luaj.vm2.lib.jse.JavaArray;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Helper class to coerce values from Java to lua within the luajava library.
+ * <p>
+ * This class is primarily used by the {@link org.luaj.vm2.lib.jse.LuajavaLib},
+ * but can also be used directly when working with Java/lua bindings.
+ * <p>
+ * To coerce scalar types, the various, generally the {@code valueOf(type)} methods
+ * on {@link LuaValue} may be used:
+ * <ul>
+ * <li>{@link LuaValue#valueOf(boolean)}</li>
+ * <li>{@link LuaValue#valueOf(byte[])}</li>
+ * <li>{@link LuaValue#valueOf(double)}</li>
+ * <li>{@link LuaValue#valueOf(int)}</li>
+ * <li>{@link LuaValue#valueOf(String)}</li>
+ * </ul>
+ * <p>
+ * To coerce arrays of objects and lists, the {@code listOf(..)} and {@code tableOf(...)} methods
+ * on {@link LuaValue} may be used:
+ * <ul>
+ * <li>{@link LuaValue#listOf(LuaValue[])}</li>
+ * <li>{@link LuaValue#listOf(LuaValue[], org.luaj.vm2.Varargs)}</li>
+ * <li>{@link LuaValue#tableOf(LuaValue[])}</li>
+ * <li>{@link LuaValue#tableOf(LuaValue[], LuaValue[], org.luaj.vm2.Varargs)}</li>
+ * </ul>
+ * The method {@link org.luaj.vm2.lib.jse.CoerceJavaToLua#coerce(Object)} looks as the type and dimesioning
+ * of the argument and tries to guess the best fit for corrsponding lua scalar,
+ * table, or table of tables.
+ *
+ * @see org.luaj.vm2.lib.jse.CoerceJavaToLua#coerce(Object)
+ * @see org.luaj.vm2.lib.jse.LuajavaLib
+ */
+public class CoerceJavaToLua {
+
+    static final Map<Class<?>, Coercion> COERCIONS = Collections.synchronizedMap(new HashMap<>());
+
+    static final Coercion instanceCoercion = new InstanceCoercion();
+    static final Coercion arrayCoercion = new ArrayCoercion();
+    static final Coercion luaCoercion = new LuaCoercion();
+
+    static {
+        Coercion boolCoercion = new BoolCoercion();
+        Coercion intCoercion = new IntCoercion();
+        Coercion charCoercion = new CharCoercion();
+        Coercion doubleCoercion = new DoubleCoercion();
+        Coercion stringCoercion = new StringCoercion();
+        Coercion bytesCoercion = new BytesCoercion();
+        Coercion classCoercion = new ClassCoercion();
+        COERCIONS.put(Boolean.class, boolCoercion);
+        COERCIONS.put(Byte.class, intCoercion);
+        COERCIONS.put(Character.class, charCoercion);
+        COERCIONS.put(Short.class, intCoercion);
+        COERCIONS.put(Integer.class, intCoercion);
+        COERCIONS.put(Long.class, doubleCoercion);
+        COERCIONS.put(Float.class, doubleCoercion);
+        COERCIONS.put(Double.class, doubleCoercion);
+        COERCIONS.put(String.class, stringCoercion);
+        COERCIONS.put(byte[].class, bytesCoercion);
+        COERCIONS.put(Class.class, classCoercion);
+    }
+
+    /**
+     * Coerse a Java object to a corresponding lua value.
+     * <p>
+     * Integral types {@code boolean}, {@code byte},  {@code char}, and {@code int}
+     * will become {@link LuaInteger};
+     * {@code long}, {@code float}, and {@code double} will become {@link LuaDouble};
+     * {@code String} and {@code byte[]} will become {@link LuaString};
+     * types inheriting from {@link LuaValue} will be returned without coercion;
+     * other types will become {@link LuaUserdata}.
+     *
+     * @param o Java object needing conversion
+     * @return {@link LuaValue} corresponding to the supplied Java value.
+     * @see LuaValue
+     * @see LuaInteger
+     * @see LuaDouble
+     * @see LuaString
+     * @see LuaUserdata
+     */
+    public static LuaValue coerce(Object o) {
+        if (o == null)
+            return LuaValue.NIL;
+        Class<?> clazz = o.getClass();
+        Coercion c = COERCIONS.get(clazz);
+        if (c == null) {
+            c = clazz.isArray() ? arrayCoercion :
+                    o instanceof LuaValue ? luaCoercion :
+                            instanceCoercion;
+            COERCIONS.put(clazz, c);
+        }
+        return c.coerce(o);
+    }
+
+    interface Coercion {
+        LuaValue coerce(Object javaValue);
+    }
+
+    private static final class BoolCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            boolean b = (Boolean) javaValue;
+            return b ? LuaValue.TRUE : LuaValue.FALSE;
+        }
+    }
+
+    private static final class IntCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            Number n = (Number) javaValue;
+            return LuaInteger.valueOf(n.intValue());
+        }
+    }
+
+    private static final class CharCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            Character c = (Character) javaValue;
+            return LuaInteger.valueOf(c);
+        }
+    }
+
+    private static final class DoubleCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            Number n = (Number) javaValue;
+            return LuaDouble.valueOf(n.doubleValue());
+        }
+    }
+
+    private static final class StringCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            return LuaString.valueOf(javaValue.toString());
+        }
+    }
+
+    private static final class BytesCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            return LuaValue.valueOf((byte[]) javaValue);
+        }
+    }
+
+    private static final class ClassCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            return JavaClass.forClass((Class<?>) javaValue);
+        }
+    }
+
+    private static final class InstanceCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            return new JavaInstance(javaValue);
+        }
+    }
+
+    private static final class ArrayCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            // should be userdata?
+            return new JavaArray(javaValue);
+        }
+    }
+
+    private static final class LuaCoercion implements Coercion {
+        public LuaValue coerce(Object javaValue) {
+            return (LuaValue) javaValue;
+        }
+    }
+}

LuaJEngine/src/main/java/org/anime_game_servers/luaj_engine/coerse/JavaClass.java

@@ -0,0 +1,37 @@
+package org.anime_game_servers.luaj_engine.coerse;
+
+import org.anime_game_servers.lua.utils.LuaHelpersJvmKt;
+import org.luaj.vm2.LuaValue;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+public class JavaClass extends org.luaj.vm2.lib.jse.JavaClass {
+
+    protected static final Map<Class<?>, JavaClass> classes = Collections.synchronizedMap(new HashMap<>());
+    JavaClass(Class c) {
+        super(c);
+    }
+
+    public static JavaClass forClass(Class<?> c) {
+        return classes.computeIfAbsent(c, JavaClass::new);
+    }
+
+    @Override
+    protected void addField(Field fi, Map<LuaValue, Field> m) {
+        if (Modifier.isPublic(fi.getModifiers())) {
+            var names = LuaHelpersJvmKt.getLuaNames(fi);
+            for (var name : names) {
+                m.put(LuaValue.valueOf(name), fi);
+            }
+            try {
+                if (!fi.isAccessible())
+                    fi.setAccessible(true);
+            } catch (SecurityException s) {
+            }
+        }
+    }
+}

LuaJEngine/src/main/java/org/anime_game_servers/luaj_engine/coerse/JavaInstance.java

@@ -0,0 +1,49 @@
+package org.anime_game_servers.luaj_engine.coerse;
+
+import org.luaj.vm2.LuaError;
+import org.luaj.vm2.LuaUserdata;
+import org.luaj.vm2.LuaValue;
+import org.luaj.vm2.lib.jse.CoerceLuaToJava;
+
+import java.lang.reflect.Field;
+
+public class JavaInstance extends LuaUserdata {
+    JavaClass jclass;
+
+    public JavaInstance(Object instance) {
+        super(instance);
+    }
+
+    public LuaValue get(LuaValue key) {
+        if (jclass == null)
+            jclass = JavaClass.forClass(m_instance.getClass());
+        Field f = jclass.getField(key);
+        if (f != null)
+            try {
+                return CoerceJavaToLua.coerce(f.get(m_instance));
+            } catch (Exception e) {
+                throw new LuaError(e);
+            }
+        LuaValue m = jclass.getMethod(key);
+        if (m != null)
+            return m;
+        Class<?> c = jclass.getInnerClass(key);
+        if (c != null)
+            return JavaClass.forClass(c);
+        return super.get(key);
+    }
+
+    public void set(LuaValue key, LuaValue value) {
+        if (jclass == null)
+            jclass = JavaClass.forClass(m_instance.getClass());
+        Field f = jclass.getField(key);
+        if (f != null)
+            try {
+                f.set(m_instance, CoerceLuaToJava.coerce(value, f.getType()));
+                return;
+            } catch (Exception e) {
+                throw new LuaError(e);
+            }
+        super.set(key, value);
+    }
+}

base/src/commonMain/kotlin/org/anime_game_servers/lua/models/StringLuaValue.kt

@@ -0,0 +1,30 @@
+package org.anime_game_servers.lua.models
+
+import org.anime_game_servers.lua.engine.Class
+import kotlin.jvm.JvmField
+
+open class StringLuaValue(protected val value: String) : MockLuaValue {
+    override fun isInteger() = true
+
+    override fun asBoolean() = when(value.lowercase()){
+        "true" -> true
+        "false" -> false
+        else -> try {
+            value.toInt() != 0
+        } catch (e: NumberFormatException) {
+            false
+        }
+    }
+    override fun asInteger() = value.toInt()
+    override fun asLong() = value.toLong()
+    override fun asDouble() = value.toDouble()
+    override fun asFloat() = value.toFloat()
+    override fun asString() = value
+
+    override fun <T> asObject(type: Class<T>): T? = null
+
+    companion object {
+        @JvmField
+        val EMPTY = StringLuaValue("")
+    }
+}

base/src/jvmMain/kotlin/org/anime_game_servers/lua/engine/LuaEngine.kt

@@ -6,6 +6,7 @@ import org.anime_game_servers.core.base.interfaces.IntKey
 import org.anime_game_servers.core.base.interfaces.IntValueEnum
 import org.anime_game_servers.lua.models.ScriptType
 import org.anime_game_servers.lua.serialize.Serializer
+import org.anime_game_servers.lua.utils.getLuaName
 import org.reflections.Reflections
 import java.nio.file.Path
 
@@ -44,19 +45,13 @@ interface LuaEngine {
         }
     }
 
-    private fun getLuaName(classObject: Class<*>): String {
-        return classObject.getAnnotation(LuaNames::class.java)?.let {
-            it.value.firstOrNull() ?: classObject.simpleName
-        } ?: classObject.simpleName
-    }
-
     fun addGlobals() {
         registeredEnums.forEach { enumClass ->
             val enumArray = enumClass.enumConstants
-            addGlobalEnum(getLuaName(enumClass), enumArray)
+            addGlobalEnum(enumClass.getLuaName(), enumArray)
         }
         registeredStaticClasses.forEach { staticClass ->
-            addGlobalStaticClass(getLuaName(staticClass), staticClass)
+            addGlobalStaticClass(staticClass.getLuaName(), staticClass)
         }
     }
 

base/src/jvmMain/kotlin/org/anime_game_servers/lua/serialize/BaseSerializer.kt

@@ -4,6 +4,7 @@ import com.esotericsoftware.reflectasm.ConstructorAccess
 import com.esotericsoftware.reflectasm.MethodAccess
 import io.github.oshai.kotlinlogging.KotlinLogging.logger
 import org.anime_game_servers.core.base.annotations.lua.LuaNames
+import org.anime_game_servers.lua.utils.getLuaNames
 import java.lang.reflect.Field
 import java.lang.reflect.ParameterizedType
 import java.lang.reflect.TypeVariable
@@ -47,7 +48,7 @@ abstract class BaseSerializer : Serializer {
             Arrays.stream(classtype.declaredFields)
                 .forEach { field: Field ->
                     val name = field.name
-                    val luaNames = getLuaNames(field)
+                    val luaNames = field.getLuaNames()
                     val fieldMeta = if (methodNameSet.contains(getSetterName(name))) {
                         val setter = getSetterName(name)
                         val index = methodAccess.getIndex(setter)
@@ -68,7 +69,7 @@ abstract class BaseSerializer : Serializer {
             .filter { field: Field -> methodNameSet.contains(getSetterName(field.name)) }
             .forEach { field: Field ->
                 val name = field.name
-                val luaNames = getLuaNames(field)
+                val luaNames = field.getLuaNames()
                 val setter = getSetterName(name)
                 val index = methodAccess.getIndex(setter)
                 val fieldMeta = FieldMeta(name, luaNames, setter, index, field.type, field)
@@ -81,18 +82,6 @@ abstract class BaseSerializer : Serializer {
         return fieldMetaMap
     }
 
-    protected fun getLuaNames(field: Field): List<String> {
-        val luaName: MutableList<String> = mutableListOf(field.name)
-        field.annotations
-            .filterIsInstance<LuaNames>()
-            .forEach { luaNames: LuaNames ->
-                if (luaNames.value.isNotEmpty()) {
-                    luaName.addAll(luaNames.value)
-                }
-            }
-        return luaName
-    }
-
     protected fun set(`object`: Any?, @Nonnull fieldMeta: FieldMeta, methodAccess: MethodAccess?, value: Int) {
         try {
             if (methodAccess != null && fieldMeta.setter != null) {

base/src/jvmMain/kotlin/org/anime_game_servers/lua/utils/LuaHelpersJvm.kt

@@ -3,8 +3,12 @@ package org.anime_game_servers.lua.utils
 import kotlinx.io.Source
 import kotlinx.io.asSource
 import kotlinx.io.buffered
+import org.anime_game_servers.core.base.annotations.lua.LuaNames
 import java.io.IOException
 import java.io.InputStream
+import java.lang.reflect.AnnotatedElement
+import java.lang.reflect.Field
+import java.lang.reflect.Member
 import java.nio.file.Files
 import java.nio.file.Path
 
@@ -17,3 +21,21 @@ fun Path.asSource(): Source {
     val stream = Files.newInputStream(this)
     return stream.asSource().buffered()
 }
+
+fun Member.getLuaNames(): List<String> {
+    val luaName: MutableList<String> = mutableListOf(name)
+    (this as? AnnotatedElement)?.let {
+        annotations
+            .filterIsInstance<LuaNames>()
+            .forEach { luaNames: LuaNames ->
+                if (luaNames.value.isNotEmpty()) {
+                    luaName.addAll(luaNames.value)
+                }
+            }
+    }
+    return luaName
+}
+
+fun Class<*>.getLuaName()= getAnnotation(LuaNames::class.java)?.let {
+        it.value.firstOrNull() ?: simpleName
+    } ?: simpleName

base/src/jvmTest/kotlin/org/anime_game_servers/lua/test/execution/CallingJavaFunctions.kt

@@ -133,11 +133,12 @@ abstract class ParsingTest{
         val context = LuaContext(engine)
 
         assert(script.hasMethod("expectIntArray"))
-        val luaValue = script.callMethod("expectIntArray", context)
+        val luaValue = script.callMethod("expectIntArray", context)!!
-        luaValue?.isLong()
+        assert(luaValue.isTable())
+
         assert(script.hasMethod("expectObjectTable"))
-        val objectTableResult = script.callMethod("expectObjectTable", context)
+        val objectTableResult = script.callMethod("expectObjectTable", context)!!
-        objectTableResult?.isLong()
+        assert(objectTableResult.isTable())
 
         // TODO test nested tables
         // TODO test mixed tables (int+string keys)

base/src/jvmTest/resources/CallingJavaFunctionsTest.lua

@@ -5,7 +5,7 @@ function expectIntArray(context)
     local array = KotlinFunctions.expectIntArray(context, param)
     for i,v in ipairs(array) do
         if v == Nil then
-            return Nil
+            return i
         end
     end
     return array
@@ -17,14 +17,14 @@ function expectObjectTable(context)
     local z = 3
     local result = KotlinFunctions.expectObjectTable(context, {x=x, y=y, z=z})
 
-    if(result.x ~= x) then
+    if result.x ~= x then
-        return Nil
+        return "X"
     end
-    if(result.y ~= y) then
+    if result.y ~= y then
-        return Nil
+        return "Y"
     end
-    if(result.z ~= z) then
+    if result.z ~= z then
-        return Nil
+        return "Z"
     end
 
     return result