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LUAK - Kotlin port of LuaJ (fork of https://github.com/korlibs/korge-luak)
/*******************************************************************************
* Copyright (c) 2009-2011 Luaj.org. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package org.luaj.vm2.lib.jse
import org.luaj.vm2.LuaDouble
import org.luaj.vm2.LuaInteger
import org.luaj.vm2.LuaString
import org.luaj.vm2.LuaUserdata
import org.luaj.vm2.LuaValue
/**
* Helper class to coerce values from Java to lua within the luajava library.
*
*
* This class is primarily used by the [LuajavaLib],
* but can also be used directly when working with Java/lua bindings.
*
*
* To coerce scalar types, the various, generally the `valueOf(type)` methods
* on [LuaValue] may be used:
*
* * [LuaValue.valueOf]
* * [LuaValue.valueOf]
* * [LuaValue.valueOf]
* * [LuaValue.valueOf]
* * [LuaValue.valueOf]
*
*
*
* To coerce arrays of objects and lists, the `listOf(..)` and `tableOf(...)` methods
* on [LuaValue] may be used:
*
* * [LuaValue.listOf]
* * [LuaValue.listOf]
* * [LuaValue.tableOf]
* * [LuaValue.tableOf]
*
* The method [CoerceJavaToLua.coerce] 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 CoerceJavaToLua.coerce
* @see LuajavaLib
*/
object CoerceJavaToLua {
internal val COERCIONS: MutableMap, Coercion> = HashMap()
internal val instanceCoercion: Coercion = InstanceCoercion()
internal val arrayCoercion: Coercion = ArrayCoercion()
internal val luaCoercion: Coercion = LuaCoercion()
internal interface Coercion {
fun coerce(javaValue: Any): LuaValue
}
private class BoolCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
val b = javaValue as Boolean
return if (b) LuaValue.BTRUE else LuaValue.BFALSE
}
}
private class IntCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
val n = javaValue as Number
return LuaInteger.valueOf(n.toInt())
}
}
private class CharCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
val c = javaValue as Char
return LuaInteger.valueOf(c.toInt())
}
}
private class DoubleCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
val n = javaValue as Number
return LuaDouble.valueOf(n.toDouble())
}
}
private class StringCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
return LuaString.valueOf(javaValue.toString())
}
}
private class BytesCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
return LuaValue.valueOf(javaValue as ByteArray)
}
}
private class ClassCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
return JavaClass.forClass(javaValue as Class<*>)
}
}
private class InstanceCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
return JavaInstance(javaValue)
}
}
private class ArrayCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
// should be userdata?
return JavaArray(javaValue)
}
}
private class LuaCoercion : Coercion {
override fun coerce(javaValue: Any): LuaValue {
return javaValue as LuaValue
}
}
init {
val boolCoercion = BoolCoercion()
val intCoercion = IntCoercion()
val charCoercion = CharCoercion()
val doubleCoercion = DoubleCoercion()
val stringCoercion = StringCoercion()
val bytesCoercion = BytesCoercion()
val classCoercion = ClassCoercion()
COERCIONS[Boolean::class.javaObjectType] = boolCoercion
COERCIONS[Byte::class.javaObjectType] = intCoercion
COERCIONS[Char::class.javaObjectType] = charCoercion
COERCIONS[Short::class.javaObjectType] = intCoercion
COERCIONS[Int::class.javaObjectType] = intCoercion
COERCIONS[Long::class.javaObjectType] = doubleCoercion
COERCIONS[Float::class.javaObjectType] = doubleCoercion
COERCIONS[Double::class.javaObjectType] = doubleCoercion
COERCIONS[String::class.javaObjectType] = stringCoercion
COERCIONS[ByteArray::class.javaObjectType] = bytesCoercion
COERCIONS[Class::class.javaObjectType] = classCoercion
}
/**
* Coerse a Java object to a corresponding lua value.
*
*
* Integral types `boolean`, `byte`, `char`, and `int`
* will become [LuaInteger];
* `long`, `float`, and `double` will become [LuaDouble];
* `String` and `byte[]` will become [LuaString];
* types inheriting from [LuaValue] will be returned without coercion;
* other types will become [LuaUserdata].
* @param o Java object needing conversion
* @return [LuaValue] corresponding to the supplied Java value.
* @see LuaValue
*
* @see LuaInteger
*
* @see LuaDouble
*
* @see LuaString
*
* @see LuaUserdata
*/
fun coerce(o: Any?): LuaValue {
if (o == null)
return LuaValue.NIL
val clazz = o.javaClass
var c: Coercion? = COERCIONS[clazz]
if (c == null) {
c = when {
clazz.isArray -> arrayCoercion
o is LuaValue -> luaCoercion
else -> instanceCoercion
}
COERCIONS[clazz] = c
}
return c.coerce(o)
}
}