Let us see an example first to understand how a string looks with left padding −
demotext //left padding with spaces 0000000demotext //left padding with 7 zeros
The following is our string −
String str = "Jack";
Now take a StringBuilder object −
StringBuilder strBuilder = new StringBuilder();
Perform left padding and extend the string length. The spaces that will be padded comes on the left. Append the spaces here −
while (strBuilder.length() + str.length() < 10) { strBuilder.append(' '); }
The following is an example to pad a string to the left with spaces
public class Demo { public static void main(String[] args) { String str = "Jack"; StringBuilder strBuilder = new StringBuilder(); // left padding with spaces while (strBuilder.length() + str.length() < 10) { strBuilder.append(' '); } // append strBuilder.append(str); String res = strBuilder.toString(); System.out.println(res); } }
Jack