Sample A (using org.apache.commons.codec.binary.Base64):
Base64.encodeBase64("foobar".getBytes());
Sample B (using android.util.Base64):
Base64.encode("foobar".getBytes(), Base64.DEFAULT);
Do these produce the same string?
No, the difference is that with the default settings, Android's Base64 includes line terminators. To obtain the same result as with the Apache encoding, use Base64.NO_WRAP.