How can I pad an integer with zeros on the left?
How do you left pad an int
with zeros when converting to a String
in java?
I'm basically looking to pad out integers up to 9999
with leading zeros (e.g. 1 = 0001
).
Solution 1:
Use java.lang.String.format(String,Object...)
like this:
String.format("%05d", yournumber);
for zero-padding with a length of 5. For hexadecimal output replace the d
with an x
as in "%05x"
.
The full formatting options are documented as part of java.util.Formatter
.
Solution 2:
Let's say you want to print 11
as 011
You could use a formatter: "%03d"
.
You can use this formatter like this:
int a = 11;
String with3digits = String.format("%03d", a);
System.out.println(with3digits);
Alternatively, some java methods directly support these formatters:
System.out.printf("%03d", a);
Solution 3:
If you for any reason use pre 1.5 Java then may try with Apache Commons Lang method
org.apache.commons.lang.StringUtils.leftPad(String str, int size, '0')
Solution 4:
Found this example... Will test...
import java.text.DecimalFormat;
class TestingAndQualityAssuranceDepartment
{
public static void main(String [] args)
{
int x=1;
DecimalFormat df = new DecimalFormat("00");
System.out.println(df.format(x));
}
}
Tested this and:
String.format("%05d",number);
Both work, for my purposes I think String.Format is better and more succinct.
Solution 5:
Try this one:
import java.text.DecimalFormat;
DecimalFormat df = new DecimalFormat("0000");
String c = df.format(9); // Output: 0009
String a = df.format(99); // Output: 0099
String b = df.format(999); // Output: 0999