java string base64 encoded

Question

I need a way to know if a string is Base64 encoded... any idea ?

thanks

take a look at this answer http://stackoverflow.com/questions/1677497/guessing-the-encoding-of-text-represented-as-byte-in-java/1678810#1678810 — Boris Pavlović, Oct 22 '10 at 07:47

score 4 · Accepted Answer · edited Oct 22 '10 at 08:20

4

The string length hast to be a multiple of 4 and only the following characters are allowed A-Z, a-z, 0-9 *+, */ and = as padding character (only at the end)

edited Oct 22 '10 at 08:20

phihag

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answered Oct 22 '10 at 07:46

Nikolaus Gradwohl

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score 4 · Answer 2 · answered Oct 22 '10 at 07:49

4

IMHO you need to try to decode it, and if it fails - it is not encoded.

There are many Base64 decoders for Java, here are some:

sun.misc.BASE64Decoder

Apache codec

http://migbase64.sourceforge.net/

http://www.source-code.biz/base64coder/java/

answered Oct 22 '10 at 07:49

Alex Abdugafarov

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java string base64 encoded

2 Answers2