java output hex (ByteArrayOutputStream)

Question

I have :

ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
encoder.encode(question, outputStream);

and when System.out.println(outputStream) prints this .. i see 0►☻☺♣▬♂test some and I want to see this in HEX like 30 04 12 54 33

How can I do that ?

Thanks

I was able to write the binary to a file like this :

File file = new File("out.bin");
FileOutputStream filename = new FileOutputStream(file);
outputStream.writeTo(filename);

for my case is there a solution ? just for this example .. i'm not so good at this so ... :| — pufos
– pufos, Commented Mar 29, 2012 at 13:19
I write the binary to a file like outputStream.writeTo(filename) where file is File file = new File("out.bin"); FileOutputStream filename = new FileOutputStream(file); — pufos
– pufos, Commented Mar 29, 2012 at 14:55

ControlAltDel · Accepted Answer · 2012-03-29 12:58:00Z

1

Can use use Integer.toHexString()? http://docs.oracle.com/javase/7/docs/api/java/lang/Integer.html#toHexString(int)

answered Mar 29, 2012 at 12:58

ControlAltDel

35.2k10 gold badges60 silver badges86 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

pufos Over a year ago

and in my actual case ? i'm trying to figure out because i never did this ... thank you

dragon66 · Accepted Answer · 2012-03-29 18:35:32Z

0

Although the System.out.println() method can print different things out, it is mainly for printing strings. For this purpose, it will try to convert the input into character string according to the platform or some explicitly given character encoding. To print raw bytes as hex, you need some manipulation before printing them out. The following example might be useful to you.

import java.io.*;

class PrintHex
{
    public static void main(String[] args) 
    {
        byte[] raw = {0x30,0x04,0x12,0x54,0x33};
        byte[] raw1 = {'G','I','F'};
        ByteArrayOutputStream bo = new ByteArrayOutputStream();
        ByteArrayOutputStream bo1 = new ByteArrayOutputStream();
        bo.write(raw,0,raw.length);
        bo1.write(raw1,0,raw1.length);

        System.out.println(bo);
        System.out.println(bo1);

        System.out.println("0x" + getHex(raw));
        System.out.println("0x" + getHex(raw1));
    }
    static final String HEXES = "0123456789ABCDEF";

    public static String getHex( byte [] raw ) {
        if ( raw == null ) {
           return null;
        }
        final StringBuilder hex = new StringBuilder( 2 * raw.length );
        for ( final byte b : raw ) {
           hex.append(HEXES.charAt((b & 0xF0) >> 4))
         .append(HEXES.charAt((b & 0x0F)));
        }
        return hex.toString();
   }
}

The getHex method is from http://www.rgagnon.com/javadetails/java-0596.html

edited Mar 29, 2012 at 18:35

answered Mar 29, 2012 at 13:44

dragon66

2,7152 gold badges25 silver badges47 bronze badges

1 Comment

dragon66 Over a year ago

pufos, what do you mean by binary to hex? ByteArrayOutputStream to hex? Change ByteArrayOutputStream to byte array first, than use the above method.

Collectives™ on Stack Overflow

java output hex (ByteArrayOutputStream)

2 Answers 2

1 Comment

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related