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Phoenix framework: How to decode Phoenix Session Cookie with Java

I am trying two different ways to decode Phoenix Session Cookie.
First one is Elixir's interaction shell, and the second one is with Java.
Please see the following examples;
IEx
iex(1)> set_cookie = "SFMyNTY.g3QAAAABbQAAAAtfY3NyZl90b2tlbm0AAAAYZFRuNUtQMkJ5YWtKT1JnWUtCeXhmNmdP.l0T3G-i8I5dMwz7lEZnQAeK_WeqEZTxcDeyNY2poz_M"
"SFMyNTY.g3QAAAABbQAAAAtfY3NyZl90b2tlbm0AAAAYZFRuNUtQMkJ5YWtKT1JnWUtCeXhmNmdP.l0T3G-i8I5dMwz7lEZnQAeK_WeqEZTxcDeyNY2poz_M"
iex(2)> [_, payload, _] = String.split(set_cookie, ".", parts: 3)
["SFMyNTY",
"g3QAAAABbQAAAAtfY3NyZl90b2tlbm0AAAAYZFRuNUtQMkJ5YWtKT1JnWUtCeXhmNmdP",
"l0T3G-i8I5dMwz7lEZnQAeK_WeqEZTxcDeyNY2poz_M"]
iex(3)> {:ok, encoded_term } = Base.url_decode64(payload, padding: false)
{:ok,
<<131, 116, 0, 0, 0, 1, 109, 0, 0, 0, 11, 95, 99, 115, 114, 102, 95, 116, 111,
107, 101, 110, 109, 0, 0, 0, 24, 100, 84, 110, 53, 75, 80, 50, 66, 121, 97,
107, 74, 79, 82, 103, 89, 75, 66, 121, 120, 102, ...>>}
iex(4)> :erlang.binary_to_term(encoded_term)
%{"_csrf_token" => "dTn5KP2ByakJORgYKByxf6gO"}
Java
public static String decodePhoenixSessionCookie(String sessionCookie) {
String payload = sessionCookie.split("\\.")[1];
byte[] encoded_term = Base64.getUrlDecoder().decode(payload.getBytes());
return new String(encoded_term);
}
Java Output
�tm_csrf_tokenmdTn5KP2ByakJORgYKByxf6gO
What I wonder is; with the Java way, I can fully achieve field name and it's value, but some gibberish values come with them.
Do you know what's the reason for this?
Do I have a chance to get clean output like Elixir way in Java way?

Cannot use unicode filename as argument to Java program on Windows cmd, but wildcard works

I tried to pass filename with unicode characters to my java program in Windows cmd, but the filename I got in program was broken. Those unicode characters were presented as ?, and it threw IOException when I read those file.
However, if I use wildcard like *.txt, it works correctly.
For example, I have a file called [テスト]测试文件1.txt in my directory.
And I wrote a simple java program to show arguments it received, which also prints string bytes.
import java.util.Arrays;
public class FileArg {
public static void main(String[] args) {
for (String fn: args) {
System.out.println(fn);
System.out.println(Arrays.toString(fn.getBytes()));
}
}
}
My Java version is 15, and I have chcp to 65001, also running program with -Dfile.encoding=UTF-8 flag.
Then I run java -Dfile.encoding=UTF-8 FileArg "[テスト]测试文件1.txt" [テスト]测试文件1.txt *.txt.
The filename is broken if I passed them directly, but it works perfectly with wildcard.
The output:
[???]??文件1.txt
[91, 63, 63, 63, 93, 63, 63, -26, -106, -121, -28, -69, -74, 49, 46, 116, 120, 116]
[???]??文件1.txt
[91, 63, 63, 63, 93, 63, 63, -26, -106, -121, -28, -69, -74, 49, 46, 116, 120, 116]
[テスト]测试文件1.txt
[91, -29, -125, -122, -29, -126, -71, -29, -125, -120, 93, -26, -75, -117, -24, -81, -107, -26, -106, -121, -28, -69, -74, 49, 46, 116, 120, 116]
Result:
BTW, my default code page is cp950 (BIG5).
How could I get it work?

How to get key & value from Kafka RecordHeaders

I have a ProducerRecord object.
ProducerRecord<String, byte[]> hdr = addHeader.addMDGHeader(record);
I'm trying to write a test that checks a particular header key exists.
If I print hdr.headers().toString() I get the following RecordHeaders(headers = [RecordHeader(key = mdpHeader, value = [123, 34, 83, 101, 113, 117, 101, 110, 99, 101, 78, 111, 34, 58, 48, 44, 34, 84, 101, 109, 112, 108, 97, 116, 101, 115, 34, 58, 91, 93, 125])], isReadOnly = false).
How do I pull out mdpHeader?

The Header.value() method returns byte array byte[], and then you can convert it into string, you can see more examples here
String value = new String(header.value(), StandardCharsets.UTF_8);

MD5 generate different result between C# and Java [closed]

Closed. This question is not reproducible or was caused by typos. It is not currently accepting answers.
This question was caused by a typo or a problem that can no longer be reproduced. While similar questions may be on-topic here, this one was resolved in a way less likely to help future readers.
Closed 7 years ago.
Improve this question
I have a byte array, and I want to compute the MD5 hash in java and C# separately. However, their generate very different result.
below is my C# code:
byte[] input = { 90, 12, 200, 139, 85, 104, 9, 202, 0, 0, 0, 0, 28, 251, 54, 201, 233, 153, 79, 1 };
MD5 md5 = MD5.Create();
byte[] result = md5.ComputeHash(input);
It generate md5 hash: 85,126,37,15,86,254,54,94,243,185,219,84,21,17,192,153,.
and below is the java code:
byte[] input = {90,12,-56,-117,85,104,9,-54,0,0,0,0,28,-5,54,-47,-23,-103,79,1};
byte[] md5 = MessageDigest.getInstance("MD5").digest(input);
and it results in:
-56,-74,-89,-76,9,35,-83,-89,-73,-39,17,83,24,18,-91,-62,
As you can see, the results are quite different. I know c# use unsigned byte, java uses signed byte. There is no way make me believe the results are identical.
Thanks in advance.

Your C# and Java inputs aren't the same.
Let's try to convert the C# input to signed bytes:
byte[] input = { 90, 12, 200, 139, 85, 104, 9, 202, 0, 0, 0, 0, 28, 251, 54, 201, 233, 153, 79, 1 };
sbyte[] signedInput = input.Select(i => unchecked((sbyte)i)).ToArray();
Console.WriteLine(string.Join(", ", signedInput));
This outputs:
90, 12, -56, -117, 85, 104, 9, -54, 0, 0, 0, 0, 28, -5, 54, -55, -23, -103, 79, 1
There's a different byte here, in bold. The Java version contains -47 at this offset.
And just to be sure, we can do a simple check using the Java version's input:
var javaInput = new[] { 90, 12, -56, -117, 85, 104, 9, -54, 0, 0, 0, 0, 28, -5, 54, -47, -23, -103, 79, 1 };
var javaInputUnsigned = javaInput.Select(i => unchecked((byte)i)).ToArray();
var hash = MD5.Create().ComputeHash(javaInputUnsigned).Select(i => unchecked((sbyte)i)).ToArray();
Console.WriteLine(string.Join(", ", hash));
This yields the same result as in the Java version:
-56, -74, -89, -76, 9, 35, -83, -89, -73, -39, 17, 83, 24, 18, -91, -62

Spring AMQP : CorrelationId changes between moment of sending and receiving a message

While I was testing the send and receive methods which I created for my project I ran into a strange problem.
When I send a certain message using a correlationId that is based on a UUID object, the receiving party gets a slightly modified version of this correlationId (which cannot be deserialised).
On the sending side I do this:
MessageProperties properties = new MessageProperties();
properties.setCorrelationId(MessageSerializer.serialize(UUID.randomUUID().toString()));
On my last test the UUID generated was: "d4170243-9e7e-4c42-9168-f9da4debc5bb"
This generates the following correlationId (when serialized):
[-84, -19, 0, 5, 116, 0, 36, 100, 52, 49, 55, 48, 50, 52, 51, 45, 57, 101, 55, 101, 45, 52, 99, 52, 50, 45, 57, 49, 54, 56, 45, 102, 57, 100, 97, 52, 100, 101, 98, 99, 53, 98, 98]
When I receive the message on the other side this id is slightly changed:
[-17, -65, -67, -17, -65, -67, 0, 5, 116, 0, 36, 100, 52, 49, 55, 48, 50, 52, 51, 45, 57, 101, 55, 101, 45, 52, 99, 52, 50, 45, 57, 49, 54, 56, 45, 102, 57, 100, 97, 52, 100, 101, 98, 99, 53, 98, 98]
When using the RabbitMQ management plugin I noticed that the id already changed upon arrival at the queue.
Tracing my code on the sending side brings me to the send option of the RabbitTemplate class.
RabbitTemplate template = new RabbitTemplate(connection);
template.setExchange("amq.direct");
template.setRoutingKey("some.route");
template.send(message);
But I can't figure out what's causing this problem. I guess it's just me using the correlationId option the wrong way. Could someone help me out?
Appreciate it.

Explanation is the following:
You serialize the UUID string to a byte array
Your serialization prepends non ascii character to this array ([-17, -65, -67, -17, -65, -67, 0, 5, 116, 0, 36,...])
The reference documentation states that the correlation id is a shortstr. RabbitMQ client converts this byte array to a string using
new String(yourArray , "UTF-8").
The non ascii character "corrupt" the conversion from byte[] to string
You can get the same result with the following code:
new String(MessageSerializer.serialize(UUID.randomUUID().toString()) , "UTF-8").getByte("UTF-8")
Which will return:
[-17, -65, -67, -17, -65, -67, 0, 5, 116, 0, 36, 100, 52, 49, 55, 48, 50, 52, 51, 45, 57, 101, 55, 101, 45, 52, 99, 52, 50, 45, 57, 49, 54, 56, 45, 102, 57, 100, 97, 52, 100, 101, 98, 99, 53, 98, 98]