Dinesh on Java: Struts 2 BeanTag Example

In this section, we are going to describe the Bean Tag. The Bean tag is a generic tag that is used to instantiates a class that confirms to the JavaBeans specification. This tag has a body which can contain a number of Param elements to set any mutator methods on that class.

In this tutorials, you will use the "bean" tag to instantiate a class named "UserBean", set its property via "param" element and print out the value.

Simple Bean
A simple class, later use bean tag to instantiate it.

UserBean.java

package com.dineshonjava.struts2.bean;

/**
 * @author Dinesh Rajput
 *
 */
public class UserBean {
 private String userName;
 private String userAge;
 private String userPhone;
 private String userAddress;
 public String getUserName() {
  return userName;
 }
 public void setUserName(String userName) {
  this.userName = userName;
 }
 public String getUserAge() {
  return userAge;
 }
 public void setUserAge(String userAge) {
  this.userAge = userAge;
 }
 public String getUserPhone() {
  return userPhone;
 }
 public void setUserPhone(String userPhone) {
  this.userPhone = userPhone;
 }
 public String getUserAddress() {
  return userAddress;
 }
 public void setUserAddress(String userAddress) {
  this.userAddress = userAddress;
 }
 
}

Action
An Action class to forward the request.

DataTagAction.java

package com.dineshonjava.struts2.action;

import com.dineshonjava.struts2.bean.UserBean;
import com.opensymphony.xwork2.ActionSupport;

/**
 * @author Dinesh Rajput
 *
 */
public class DataTagAction extends ActionSupport {

 private static final long serialVersionUID = -7744420104547018874L;
 private UserBean bean;
 public String execute() {
  return SUCCESS;
 }
 public UserBean getBean() {
  return bean;
 }
 public void setBean(UserBean bean) {
  this.bean = bean;
 }
 
}

Bean tag example
A JSP page to show the use of "bean" tag to instantiate the "UserBean".

<%@ page contentType="text/html; charset=UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<html>
<head>
<title>Bean Data Tag Struts2 | dineshonjava.com</title>
</head>
<body>
   <h2>An example of the Bean tag: </h2>
   <s:bean name="com.dineshonjava.struts2.bean.UserBean" var="paramTag">
  <s:param name="userName">Dinesh Rajput</s:param>
  <s:param name="userAge">27</s:param>
  <s:param name="userPhone">9998851234</s:param>
  <s:param name="userAddress">ABC Noida</s:param>
 </s:bean>
 
 <ol>
  <li>User Name : <s:property value="#paramTag.userName" /></li>
  <li>User Age : <s:property value="#paramTag.userAge" /></li>
  <li>User Phone : <s:property value="#paramTag.userPhone" /></li>
  <li>User Address : <s:property value="#paramTag.userAddress" /></li>
 </ol>
</body>
</html>

Configuration Files for struts2:
struts.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
    "http://struts.apache.org/dtds/struts-2.0.dtd">
 
<struts>
    <constant name="struts.enable.DynamicMethodInvocation" value="false" />
    <constant name="struts.devMode" value="false" />
    <constant name="struts.custom.i18n.resources" value="myapp" />
 
 <package name="default" extends="struts-default" namespace="/">
        <action name="beantag" class="com.dineshonjava.struts2.action.DataTagAction">
            <result name="success">/success.jsp</result>
        </action>
    </package>
 </struts>

create web.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>Struts2DataTag</display-name>
 <filter>
        <filter-name>struts2</filter-name>
        <filter-class>
            org.apache.struts2.dispatcher.FilterDispatcher
        </filter-class>
    </filter>
    <filter-mapping>
        <filter-name>struts2</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
</web-app>

Right click on the project name and click Export > WAR File to create a War file. Then deploy this WAR in the Tomcat's webapps directory. Finally, start Tomcat server and try to access

URL http://localhost:8080/doj/beantag.

This will give you following screen:

Download Source Code
BeanDataTagExample.zip

<<Previous << || Index || >>Next >>