android在java.util.Objects.requireNonNull中获取空指针异常（Objects.java:203）

Question

我正在阅读编写字符串数组并在Recycler视图中显示它们。在显示它们之前，我正在使用Collections.reverse（Arrays.asList（FilePathStrings））来反转顺序;以下是我得到的例外情况：

java.lang.NullPointerException
at java.util.Objects.requireNonNull(Objects.java:203)
at java.util.Arrays$ArrayList.<init>(Arrays.java:3826)
at java.util.Arrays.asList(Arrays.java:3813)
at com.example.soberapps.nightcamera.b.c.a(Unknown Source)
at android.support.v4.app.i.b(Unknown Source)
at android.support.v4.app.o.a(Unknown Source)
at android.support.v4.app.o.e(Unknown Source)
at android.support.v4.app.o.a(Unknown Source)
at android.support.v4.app.c.d(Unknown Source)
at android.support.v4.app.o.b(Unknown Source)
at android.support.v4.app.o.a(Unknown Source)
at android.support.v4.app.o.b(Unknown Source)
at android.support.v4.app.o.h(Unknown Source)
at android.support.v4.app.o$1.run(Unknown Source)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at androidx.test.espresso.base.Interrogator.a(Interrogator.java:19)
at androidx.test.espresso.base.UiControllerImpl.a(UiControllerImpl.java:164)
at androidx.test.espresso.base.UiControllerImpl.a(UiControllerImpl.java:156)
at androidx.test.espresso.base.UiControllerImpl.a(UiControllerImpl.java:34)
at androidx.test.espresso.action.MotionEvents.a(MotionEvents.java:75)
at androidx.test.espresso.action.MotionEvents.a(MotionEvents.java:50)
at androidx.test.espresso.action.Tap.c(Tap.java:8)
at androidx.test.espresso.action.Tap.a(Tap.java:18)
at androidx.test.espresso.action.Tap$1.b(Tap.java:3)
at androidx.test.espresso.action.GeneralClickAction.perform(GeneralClickAction.java:22)
at androidx.test.espresso.ViewInteraction$SingleExecutionViewAction.perform(ViewInteraction.java:9)
at androidx.test.espresso.ViewInteraction.a(ViewInteraction.java:78)
at androidx.test.espresso.ViewInteraction.a(ViewInteraction.java:94)
at androidx.test.espresso.ViewInteraction$1.call(ViewInteraction.java:3)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6316)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:872)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:762)

错误报告崩溃

java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.contains(java.lang.CharSequence)' on a null object reference
    at android.os.Parcel.readException(Parcel.java:1689)
    at android.os.Parcel.readException(Parcel.java:1636)
    at android.app.ActivityManagerProxy.handleApplicationCrash(ActivityManagerProxy.java:5217)
    at com.android.internal.os.RuntimeInit$UncaughtHandler.uncaughtException(RuntimeInit.java:97)
    at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:1068)
    at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:1063)

Answer 1

Arrays.asList(null)抛出这个例外。您的参数（FilePathStrings）等于null。