Проблема с контекстом «getApplicationContext()» для нулевой ссылки на объект» ⇐ Android

[Гость]

I made nonActivity class, and I use there other nonActivity Database class. When I call method from 1st class I have Error

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java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.Context android.content.Context.getApplicationContext()' on a null object reference

Here is a fragment of my code of both classes:

DataBase.java

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 public DataBase(Context context) {
super(context, DATABASE_NAME, null, TABLE_VERSION);
}

and ObliczPodatki.java

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public class ObliczPodatki extends Application
.
.
.
myDb = new DataBase(this.getApplicationContext());

and the full error message:

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Process: com.example.nadgraniav01, PID: 11274
java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.Context android.content.Context.getApplicationContext()' on a null object reference
at android.content.ContextWrapper.getApplicationContext(ContextWrapper.java:116)
at com.example.nadgraniav01.ObliczPodatki.obliczPodatki(ObliczPodatki.java:43)
at com.example.nadgraniav01.DodajNadgranieActivity$2.onClick(DodajNadgranieActivity.java:99)
at android.view.View.performClick(View.java:6669)
at android.view.View.performClickInternal(View.java:6638)
at android.view.View.access$3100(View.java:789)
at android.view.View$PerformClick.run(View.java:26145)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6863)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:537)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

if I use this instead of this.getApplicationContext() I am getting following erroe

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Attempt to invoke virtual method 'java.io.File android.content.Context.getDatabasePath(java.lang.String)' on a null object reference

Источник: https://stackoverflow.com/questions/566 ... -reference