Base64 encoder and decoder

Question

Is there a base-64 decoder and encoder for a String in Android?

blackpanther · Answer 1 · 2014-11-16T21:28:09.300

77

This is an example of how to use the Base64 class to encode and decode a simple String value.

// String to be encoded with Base64
String text = "Test";
// Sending side
byte[] data = null;
try {
    data = text.getBytes("UTF-8");
} catch (UnsupportedEncodingException e1) {
    e1.printStackTrace();
}
String base64 = Base64.encodeToString(data, Base64.DEFAULT);

// Receiving side
byte[] data1 = Base64.decode(base64, Base64.DEFAULT);
String text1 = null;
try {
    text1 = new String(data1, "UTF-8");
} catch (UnsupportedEncodingException e) {
    e.printStackTrace();
}

This excerpt can be included in an Android activity.

edited Nov 16 '14 at 21:28

answered Aug 22 '12 at 20:50

blackpanther

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13

using `Base64.DEFAULT` will insert a line break in my case. I use `Base64.NO_WRAP` instead. – Arvin Dec 18 '13 at 08:48
The only one which works for me with 2 bytes characters. – Jerry Jul 03 '18 at 18:14

score 33 · Accepted Answer · edited May 15 '13 at 13:30

33

See android.util.Base64

It seems that this was added in API version 8 or android 2.2 so it will not be available on the older platforms.

But the source of it is at android/util/Base64.java so if needed one could just copy it unchanged for older versions.

edited May 15 '13 at 13:30

CelinHC

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answered Dec 01 '10 at 07:42

Dan D.

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encoded Base64 of Mw== is TXc9PQ== But this source code show TXc9PQo= What's wrong?! :-o – Dr.jacky Aug 01 '14 at 12:10
2

@Mr.Hyde You have a trailing new line. TXc9PQo= decodes to `Mw==\n`. – Dan D. Aug 02 '14 at 02:39
3

Yea, and to solve it, we should use Base64.NO_WRAP for flag in encodeToString function, instead of Base64.DEFAULT. – Dr.jacky Aug 02 '14 at 08:30
hi have Base64.class but its having an error "$assertionsDisabled cannot be resolved to a variable" – Prasad Sep 13 '14 at 06:27

Jared Burrows · Answer 3 · 2019-05-13T07:26:12.647

13

Here is a simple method I was going to use until I realized that this is only supported in Android API 8+:

// Has line break
public String getBase64(String input) {
    return Base64.encodeToString(input.getBytes(), Base64.DEFAULT);
}

// No line break
public String getBase64(String input) {
    return Base64.encodeToString(input.getBytes(), Base64.NO_WRAP);
}

edited May 13 '19 at 07:26

answered Aug 26 '12 at 16:06

Jared Burrows

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as @arvin commented above: "using Base64.DEFAULT will insert a line break in my case. I use Base64.NO_WRAP instead." – AbdulMomen عبدالمؤمن Jun 30 '15 at 09:27

score 12 · Answer 4 · answered Dec 23 '15 at 22:21

To encode:

private String encodeString(String s) {
    byte[] data = new byte[0];

    try {
        data = s.getBytes("UTF-8");

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } finally {
        String base64Encoded = Base64.encodeToString(data, Base64.DEFAULT);

        return base64Encoded;

    }
}

To decode:

private String decodeString(String encoded) {
    byte[] dataDec = Base64.decode(encoded, Base64.DEFAULT);
    String decodedString = "";
    try {

        decodedString = new String(dataDec, "UTF-8");
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();

    } finally {

        return decodedString;
    }
}

Example

    String text = "example007";

    Log.e("encoded", encodeString(text)); //Output: ZXhhbXBsZTAwNw==
    Log.e("decoded", decodeString(encodeString(text))); //Output: example007

score 5 · Answer 5 · answered May 07 '15 at 07:24

5

If you don't want a line break at the end of the String, change the flags from Base64.DEFAULT to Base64.NO_WRAP

Base64.encodeToString("yourString".getBytes("UTF-8"), Base64.NO_WRAP);

answered May 07 '15 at 07:24

Hugo Gresse

17,195
9
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score 0 · Answer 6 · answered Apr 11 '23 at 06:37

Kotlin supports Base64 for versions 1.8.20 and over. It has 3 types available which are Base64.Default, Base64.UrlSafe and Base64.Mime.

// Base64.Default
val nameBytes = "Nav".map { it.code.toByte() }.toByteArray()
val encodedValue = Base64.Default.encode(nameBytes)
// Encode value: TmF2
println("Encoded: $encodedValue") 
// Decoded value: Nav
println("Decoded: ${String(Base64.Default.decode(encodedValue))}")

// Base64.UrlSafe
val googleIOUrlBytes = "google.io".map { it.code.toByte() }.toByteArray()
// Encode value: Z29vZ2xlLmlv
val encodedURLSafe = Base64.UrlSafe.encode(googleIOUrlBytes)
println("Encoded UrlSafe: $encodedURLSafe")
// Decoded value: google.io
println("Decoded UrlSafe: ${String(Base64.UrlSafe.decode(encodedURLSafe))}")

Base64 encoder and decoder

6 Answers6

To encode:

To decode:

Example

Linked

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