How to use printf() method with long values in Java?

Question

I remember that I did this in C but I couldn’t get it work in Java.

How to print long values with printf() method in Java?

I tried with below code what I actually need is to print the long value in hexadecimal way like below

long l = 32L -----> 0000000000000022

If I use %d then it prints integer value which I don’t want...

class TestPrintf() 
{
    public static void main(String[] args)
    {

    long l = 100L;

    System.out.printf(“%l”+l); // Error unknown format exception
    System.out.printf(“%d”+l); // Prints 100
    System.out.printf(“%f”+l); // Unknown illegal format conversion float != java.lang.long
    }
}

Answer 1

You need to put the actual argument to print as the next argument of a printf() methods. Concatenating will not work.

System.out.printf("%d%n", 123);             // for ints and longs
System.out.printf("%d%n", 12345L);          // for ints and longs
System.out.printf("%f%n", (double) 12345L); // for floating point numbers

Full documentation in java.util.Formatter

Answer 2

If you want a 16-character zero-padded string, with A-F in uppercase, prefixed by 0x, you should use:

System.out.printf("0x%016X", l);