kotlin 属性代理 读取Properties 中的属性

class PropertiesDelegate(val path: String) {

    val properties: Properties by lazy {
        val prop = Properties()
        try {
            javaClass.getResourceAsStream(path).use {
                prop.load(it)
            }
        } catch (e: Exception) {
            //logger.error(e.message, e)
            try {
                ClassLoader.getSystemClassLoader().getResourceAsStream(path).use {
                    prop.load(it)
                }
            } catch (e: Exception) {
                //logger.error(e.message, e)
                FileInputStream(path).use {
                    prop.load(it)
                }
            }
        }

        prop
    }

    operator fun <T> getValue(thisRef: Any, property: KProperty<*>): T {
        val value = properties[property.name]
        val classOfT = property.returnType.classifier as KClass<*>
        return if (Number::class.isSuperclassOf(classOfT)) {
            classOfT.javaObjectType.getDeclaredMethod("parse${classOfT.simpleName}", String::class.java).invoke(null, value)
        } else {
            value
        } as T
    }

    operator fun <T> setValue(thisRef: Any, property: KProperty<*>, value: T) {
        properties[property.name] = value
        File(path).outputStream().use {
            properties.store(it, "")
        }
    }
}

abstract class AbsProperties(path: String) {
    protected val prop = PropertiesDelegate(path)
}