JSTL Formatting <fmt:formatNumber> Tag

Last Updated : 14 Dec, 2023

In JSTL the <fmt:formatNumber> tag is mainly used to format the numeric value according to the specified localization setting, which also includes the grouping separators, currency symbols, and decimal separators. This function mainly simplified the presentation of numeric data in JSP by offering control over how the numbers should be displayed.

In this article, we will see the detailed syntax along with the parameters of <fmt:formatNumber> Tag. We will see the attributes, and practical implementation in terms of examples.

Syntax:

<fmt:formatNumber value="numericValue" 
                                   [type="numberType"] 
                                   [pattern="formatPattern"] 
                                   [var="resultVar"] 
                                   [scope="page|request|session|application"]
/>

Where,

value: This is the numeric value which is to be formatted.
type: This is the type of the number to format. The type of numbers is “number“, “currency” or the “percent“.
pattern: This is the optional parameter used for formatting in custom formats.
var: This is an optional parameter used to store the formatted result.
scope: This is the optional parameter that represents the scope of the variable as page, request, session, or application.

Attributes:

The table describes all the attributes present in fmt:formatNumber JSTL tag.

Attribute	Description	Required	Default
value	This is the numeric value which is to be formatted	Yes	N/A
type	This is the type of number to be formatted.	No	number
pattern	This is the format pattern for formatting the custom formats	No	N/A
maxIntegerDigits	This is the maximum number of integer digits	No	N/A
minIntegerDigits	This is the minimum number of integer digits.	No	N/A
maxFractionDigits	This is the maximum number of fraction digits	No	N/A
minFractionDigits	This is the minimum number of fraction digits	No	N/A
groupingUsed	This indicated whether the grouping separators should be used or not	No	true
var	This is the variable used to store the formatted result	No	N/A
scope	This is the scope of the variable	No	page

Example of JSTL Formatting <fmt:formatNumber> Tag

This is a JavaServer Pages (JSP) code that demonstrates the use of JSTL (JavaServer Pages Standard Tag Library) to format a numeric value using the fmt:formatNumber tag.

HTML

<%@ page contentType="text/html;charset=UTF-8" language="java" %> 
<%@ taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt" %> 
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> 
<html> 
<head> 
    <title>JSTL fmt:formatNumber Example</title> 
</head> 
<body> 
<c:set var="numericValue" value="12345.6789"/> 
  
<h3>Original Numeric Value: ${numericValue}</h3> 
<fmt:formatNumber value="${numericValue}"
                  type="currency"
                  pattern="#,###.##"
                  maxIntegerDigits="5"
                  minIntegerDigits="3"
                  maxFractionDigits="2"
                  minFractionDigits="1"
                  groupingUsed="true"
                  var="formattedNumber"
                  scope="request"/> 
<h3>Formatted Number: ${formattedNumber}</h3> 
</body> 
</html> 

Output:

Original Numeric Value: 12345.6789
Formatted Number: 12,345.68

Output of the Program

Explanation of the Above Program:

We have initialized the numericValue variable with the value “12345.6789“.
Then, the <fmt:formatNumber> tag is used to format the numeric value with different attributes.
We are storing the formatted number in the “formattedNumber” variable in the request scope.
And lastly, we are displaying both the original and formatted numbers using the <h3> tag in HTML.

Suggest improvement

JSTL Formatting <fmt:formatDate> Tag

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