Java/安卓/ Kotlin : Reflection on private Field and call public methods on it

Question

是否可以使用反射来访问对象的私有(private)字段并在该字段上调用公共(public)方法？

一个

class Hello {
   private World word
}

class World {
   public BlaBlaBla foo()
}

Hello h = new Hello()

World world = reflect on the h


// And then 

world.foo()

Answer 1

可以使用反射使私有(private)字段可访问。以下示例(均用 Kotlin 编写)展示了它...

使用 Java 反射:

val hello = Hello()
val f = hello::class.java.getDeclaredField("world")
f.isAccessible = true
val w = f.get(hello) as World
println(w.foo())

使用 Kotlin 反射:

val hello = Hello()
val f = Hello::class.memberProperties.find { it.name == "world" }
f?.let {
    it.isAccessible = true
    val w = it.get(hello) as World
    println(w.foo())
}