How to format a java string with leading zero?

Question

Here is the String, for example: "Apple", and I would like to add zero to fill in 8 chars. I would like to show the result like this;' "000Apple" How can I do so? Thank you.

Answer 1

 StringUtils.leftPad(yourString, 8, '0');

This is from commons-lang. See javadoc

Answer 2

public class LeadingZerosExample {
    public static void main(String[] args) {
    int number = 1500;

    //
    // String format below will add leading zeros (the %0 syntax) to the number above. 
        // The length of the formatted string will be 7 characters.
    //
    String formatted = String.format("%07d", number);

    System.out.println("Number with leading zeros: " + formatted);
    }
}

Answer 3

Use Apache Commons StringUtils.leftPad (or look at the code to make your own function).

Answer 4

It isn't pretty, but it works. If you have access apache commons i would suggest that use that

if (val.length() < 8) {
  for (int i = 0; i < val - 8; i++) {
    val = "0" + val;
  }
}

Answer 5

public class PaddingLeft {
    public static void main(String[] args) {
        String input = "Apple";
        String result = "00000000" + input;
        int length = result.length();
        result = result.substring(length - 8, length);
        System.out.println(result);
    }
}

Answer 6

In case you have to do it without the help of a library:

("00000000" + "Apple").substring("Apple".length())

(Works, as long as your String isn't longer than 8 chars.)

Answer 7

You may have to take care of edgecase. This is a generic method.

public class Test {
    public static void main(String[] args){
        System.out.println(padCharacter('0',8,"hello"));
    }
    public static String padCharacter(char c, int num, String str){
        for(int i=0;i<=num-str.length()+1;i++){str = c+str;}
        return str;
    }
}

Answer 8

String input = "Apple";
StringBuffer buf = new StringBuffer(input);

while (buf.length() < 8) {
  buf.insert(0, '0');
}

String output = buf.toString();