Android studio: NoClassDefFoundError with java.util.Base64
Just replace
import java.util.Base64;
with
import android.util.Base64;
And then modify your code to something like this (just an example):
String encoded = Base64.encode(someString.getBytes(), Base64.DEFAULT)); // for encoding
String decoded = Base64.decode(encoded, Base64.DEFAULT)); // for decoding
replace java.util.Base64
with android.util.Base64
. android doesn't use openjdk or oracle jre so the standard packages may not be there.