fzakaria/ascii85

A Java library for working with Ascii85, also called Base85 - a form of binary-to-text encoding

ascii85's Issues

This class do not support empty arrays

I doesn't support empty byte array

 @Test
public void testEmpty() {
    byte[] empty = new byte[0];
    String encoded = Ascii85.encode(empty);
    try 
    {
        byte[] actual = Ascii85.decode(encoded);
        assertThat(actual, is(empty));
    } 
    catch (Exception e) 
    {
        e.printStackTrace();
    }
}

Encoded string is smaller than expected and therefore allocated ByteBuffer capacity is smaller than original byte array size, causing BufferOverflowException

Encoded a JPEG frame represented by byte array with original length 25820 into a Ascii85 string with 32259 length. Which supposed to be actually 32275 = 25820 * 5 / 4;
Then try to decode that string using Ascii85.decode(); so the Allocated ByteBuffer is 25807 = 32259 * 4 / 5, which is less than original byte array length of 25820;

java.nio.BufferOverflowException
at java.nio.HeapByteBuffer.put(HeapByteBuffer.java:164)
at java.nio.ByteBuffer.put(ByteBuffer.java:642)
Ascii85.decode(Ascii85.java:143)

So somehow encoded string turns out to be shorter than byteArrLen * 5/4, which breaks assumption in decode and it causes the exception.

Thanks

Buffer overflow exception when input contains 'z's

When decoding, the formula for the output size is "input_size * 4 / 5", which does account for the fact that when input contains only 'z's output can be 4 times as large as the output.

Handling of non-ASCII characters

What is the intended behaviour of the decode function (ASCII to binary), when the input string contains characters that are neither ASCII nor whitespace? Should it fail or maybe the invalid characters should just be ignored?

does not properly encode/decode random bytes

SecureRandom random = new SecureRandom();
byte[] randoms = new byte[128];
random.nextBytes(randoms);
String encoded = Ascii85.encode(randoms);
try {
	System.out.println(toHexString(MessageDigest.getInstance("MD5").digest(randoms)));
	System.out.println(toHexString(MessageDigest.getInstance("MD5").digest(Ascii85.decode(encoded))));
} catch (Exception e) {
	e.printStackTrace();
}

This short program outputs two different hashes. Does this library not work for random bytes?

Kotlin

Hi Farid,

I ported your excellent ascii85 to kotlin here

I see you are way into several language... it's time for Kotlin! 😛

If you want I can push it and also implement gradle 😉

Maven Central Deploy

Hi,

First of all, thanks for the lib. It seems that the lib is not on maven central as advertised. Is that something that is planned to be fixed?