我有这样的java代码:
Method m = device.getClass()
.getMethod("removeBondNative", (Class[]) null);
m.invoke(device, (Object[]) null);
我正在尝试用 Kotlin 写同样的东西,如下所示:
device.javaClass.getMethod("removeBondNative", null as Class<*>).invoke(device, null as Any)
但我收到此错误消息:
Process: com.example.zemcd.toofxchange, PID: 17466
kotlin.TypeCastException: null cannot be cast to non-null type java.lang.Class<*>
at com.example.zemcd.toofxchange.BluetoothUtils$Companion.unPair(BluetoothUtils.kt:61)
at com.example.zemcd.toofxchange.DeviceAdapter$DeviceHolder$bindItems$1$$special$$inlined$forEach$lambda$1.onClick(DeviceAdapter.kt:98)
at android.view.View.performClick(View.java:5217)
at android.view.View$PerformClick.run(View.java:21349)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5585)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:730)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:620)
我还尝试将 null 更改为 Unit:
device.javaClass.getMethod("removeBondNative", Unit as Class<*>).invoke(device, null as Any)
但仍然遇到错误:
Process: com.example.zemcd.toofxchange, PID: 19219
java.lang.ClassCastException: kotlin.Unit cannot be cast to java.lang.Class
at com.example.zemcd.toofxchange.BluetoothUtils$Companion.unPair(BluetoothUtils.kt:61)
at com.example.zemcd.toofxchange.DeviceAdapter$DeviceHolder$bindItems$1$$special$$inlined$forEach$lambda$1.onClick(DeviceAdapter.kt:98)
at android.view.View.performClick(View.java:5217)
at android.view.View$PerformClick.run(View.java:21349)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5585)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:730)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:620)
我在这里做错了什么?在这种情况下,java 反射如何在 Kotlin 中镜像?
最佳答案
错误消息告诉您问题所在:Class<*>
是非空类型,因此转换为它时始终检查转换值不为空。你可以写null as Class<*>?
,但这相当于 (Class) null
。您想要null as Array<Class<*>>?
相反。
但是,无论如何,这似乎毫无意义:"If parameterTypes is null, it is treated as if it were an empty array"所以.getMethod("removeBondNative")
应该给你相同的结果。
关于java - java方法接受null类数组的kotlin反射,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/46759959/