Prepend zero to byte

Question

Hi,

I'm reading file and I want to print byte value in 2 digits if it is less than 10 (example if byte=1 it should disply byte=01), I don't want to compare it like this:

    if(byte<10){
        stringBuffer buf= new stringBuffer();
        buf.append("0"+byte);
    }

is there any built in method to do this, just like the format function in vc++?

Thanks gagana

Answer 1

See java.util.Formatter

Answer 2

java.util.Formatter

Answer 3

Take a look at the Formatter class

Answer 4

How about:

String twoDigits = String.format("%02d", myByte);

It's a lot closer to the C way of doing things rather than having to instantiate your own formatter.

Answer 5

byte b = ...
System.out.println(String.format("%02x",b));

Answer 6

For "small" values of b this should be fine:

String s = "" + b;
while(s.length() < 2) {
   s = "0" + s;
 }

Answer 7

You can use DecimalFormat:

NumberFormat nf = new DecimalFormat("00");
buf.append(df.format(byteArray[i]));

Obviously you just instantiate it once outside the loop.

Answer 8

System.out.println(new DecimalFormat("00").format(9));

prints 09 for me.

Answer 9

The 'a' is 10 in hexadecimal format.

So change your format strings from "%02x" to "%02d"

Answer 10

I'm not so convenient with java syntax... But here is a way... May be you need to find equalant of right for java

buf.append(right(("00" + byte),2))