Home Communities
IT Knowledge
Inspiration
Languages
EN

Java - convert int to binary String with leading zeros

13 points
Created by:
425

Short solution:

``````int number = 8;

String binaryString = Integer.toBinaryString(number);
String withLeadingZeros = String.format("%8s", binaryString).replace(' ', '0');

System.out.println(binaryString);     // 1000

In java simples way to convert int to binary String with leading zeros is to use `Integer.toBinaryString(number)` and `String.format()` method. Note that as first param in String format we pass number of leading spaces and we replace all spaces with 0.

1. Print int and binary representation of a number

``````public class Example1 {

public static void main(String[] args) {

System.out.println("int | binary");

int number = 8;

String binary = Integer.toBinaryString(number);
String padding = String.format("%8s", binary).replace(' ', '0');

}
}``````

Output:

``````int | binary
8 - 00001000``````

2. Print int and binary representation between 0 and 8

``````public class Example2 {

public static void main(String[] args) {

System.out.println("int | binary");

for (int i = 0; i <= 8; i++) {

String binary = Integer.toBinaryString(i);
String padding = String.format("%8s", binary).replace(' ', '0');

}
}
}``````

Output:

``````int | binary
0 - 00000000
1 - 00000001
2 - 00000010
3 - 00000011
4 - 00000100
5 - 00000101
6 - 00000110
7 - 00000111
8 - 00001000``````

3. Print int and binary representation between 0 and 255 - ASCII

``````public class Example3 {

public static void main(String[] args) {

for (int i = 0; i <= 255; i++) {

String binary = Integer.toBinaryString(i);
String padding = String.format("%8s", binary).replace(' ', '0');

}
}
}``````

Output:

``````  0 - 00000000
1 - 00000001
2 - 00000010
3 - 00000011
4 - 00000100
5 - 00000101
6 - 00000110
7 - 00000111
8 - 00001000

...

252 - 11111100
253 - 11111101
254 - 11111110
255 - 11111111``````

Merged questions

Join to our subscribers to be up to date with content, news and offers.