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Java String Formatting - How to apply zero padding in integers using String#printf()?

Java String Formatting Java 

This example shows how to append zeros before an integer with String#printf()

Syntax: %0nd where n is any positive integer

package com.logicbig.example.string;


import java.util.IllegalFormatFlagsException;

public class StringPrintfIntegerZeroPadding {

    public static void main(String[] args) {
        //padding with zeros
        System.out.printf("[%04d]%n", 9);

        //right padding with zeros is not possible
        try {
            System.out.printf("[%-04d]%n", 9);
        } catch (IllegalFormatFlagsException e) {
            System.out.println(e);
        }
    }
}

Output

[0009]
java.util.IllegalFormatFlagsException: Flags = '-0'

See Also