Is it possible to restore sources from apk?

Question

Java

Hello. Is it possible to restore the source code of the application from the apk file??
HDD ordered to live long, taking with it the source code of the last application.
Already tried dex2jar, and several online decompilers.
With the online decompiler, everything is ambiguous, it shuts up on the mainactivity with the NullPointerExtention error.
And dex2jar does not provide clarity in the decompiled code.

Answer 1

One dex2jar is not enough
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