JSF Tutorial - JSF Convert Number Example

f:convertNumber tag is used to convert a string value to a number of required format.

The following code shows how to use f:convertNumber tag

<f:convertNumber minFractionDigits="2" />

Tag Attributes

Attribute	Description
type	number (default), currency , or percent
pattern	Formatting pattern, as defined in java.text.DecimalFormat
maxFractionDigits	Maximum number of digits in the fractional part
minFractionDigits	Minimum number of digits in the fractional part
maxIntegerDigits	Maximum number of digits in the integer part
minIntegerDigits	Minimum number of digits in the integer part
integerOnly	True if only the integer part is parsed (default: false)
groupingUsed	True if grouping separators are used (default: true)
locale	Locale whose preferences are to be used for parsing and formatting
currencyCode	ISO 4217 currency code to use when converting currency values
currencySymbol	Currency symbol to use when converting currency values

Example

The following code is from demo.xhtml.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"   
      xmlns:h="http://java.sun.com/jsf/html"
      xmlns:f="http://java.sun.com/jsf/core"
      xmlns:c="http://java.sun.com/jsp/jstl/core"
      >
    <h:body>    
    <h:form>
      <h:panelGrid columns="3">
        Amount : 
        <h:inputText id="amount" value="#{receipt.amount}" 
          size="20" required="true"
          label="Amount" >
          <!-- display in at least 2 decimal points -->
          <f:convertNumber minFractionDigits="2" />
        </h:inputText>
        <h:message for="amount" style="color:red" />
      </h:panelGrid>
      <h:commandButton value="Submit" action="result" />
    </h:form>
    
    </h:body>
</html>

The following code is from UserBean.java.

package com.java2s.common;

import java.io.Serializable;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
 
@ManagedBean(name="receipt")
@SessionScoped
public class UserBean implements Serializable{
  
  double amount;

  public double getAmount() {
    return amount;
  }

  public void setAmount(double amount) {
    this.amount = amount;
  }

}

The following code is from result.xhtml.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"   
      xmlns:h="http://java.sun.com/jsf/html"
      xmlns:f="http://java.sun.com/jsf/core"
      xmlns:c="http://java.sun.com/jsp/jstl/core"
      >
    <h:body>
    <p>
      Amount [minFractionDigits="2"] : 
      <h:outputText value="#{receipt.amount}" >
        <f:convertNumber minFractionDigits="2" />
      </h:outputText>
    </p>
    <p>
      Amount [pattern="#0.000"] : 
      <h:outputText value="#{receipt.amount}" >
        <f:convertNumber pattern="#0.000" />
      </h:outputText>
    </p>
    <p>
      Amount [currencySymbol="$"] : 
      <h:outputText value="#{receipt.amount}">
        <f:convertNumber currencySymbol="$" type="currency" />
      </h:outputText>
    </p>
    <p>
      Amount [currencyCode="GBP"] : 
      <h:outputText value="#{receipt.amount}" >
        <f:convertNumber currencyCode="GBP" type="currency" />
      </h:outputText>
    </p>
    <p>
      Amount [type="percent"] : 
      <h:outputText value="#{receipt.amount}" >
        <f:convertNumber type="percent" />
      </h:outputText>
    </p>
    </h:body>
</html>

Download Convert_Number.zip

To RUN

Copy the generated WAR file from the target folder to Tomcat deployment folder and run Tomcat-Install-folder/bin/startup.bat.

After Tomcat finish starting, type the following URL in the browser address bar.

http://localhost:8080/simple-webapp/demo.xhtml