Ekiras Replica: Struts2

Points To Remember

Download the struts required jars and add to the lib folder.

Setup : Struts Hello World Example

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_2_5.xsd"
 id="WebApp_ID" version="2.5">
 <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>

Struts Filter- This filter routes all incoming requests to struts.xml. struts.xml matches the actions and provides response accordingly.
Welcome File List- this defines which file will be loaded on starting the application. We can have multiple welcome-file one followed by another.

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>
<!-- *********************  START STRUTS FILE ********************************* -->

 <package name="HelloWorld" extends="struts-default">
  
  <action name="HelloWorld" class="com.ekiras.action.Action" method="sayHello">
   <result name="success">result.jsp</result>
  </action>
 
 </package>
 
<!-- *********************  END STRUTS FILE *********************************** -->
</struts>

struts.xml contains

Package - name="any unique name" extends="any other package or struts-default" namespace="optional (default namespace if not nemtioned)"
Action name="HelloWorld" when this action is performed it sends request to function sayHello of class com.ekiras.action.Action
- Result- result="success" if the return type of method sayhello is equal to "success" then it will redirect to result.jsp page

index.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Struts Hello World</title>
</head>
<body>
<h1>Hello World Test - STRUTS 2.0</h1>
<s:form action="HelloWorld">
 <s:textfield label="Enter Your Name" name="bean.usrName"/>
 <s:submit label="Submit" />
</s:form>
</body>
</html>

This page is the welcome page in this example. It contains a text field that takes a name as an input and set's the value of useName fiels of Bean class on form submittion.
result.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib prefix="s" uri="/struts-tags"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Struts-Hello World</title>
</head>
<body>
<h1>Hello - <s:property value="bean.usrName"/></h1>
</body>
</html>

This page is loaded when the action HelloWorld is performed and the method sayHello() of class Action returns a string success.
Action.java

package com.ekiras.action;


import com.ekiras.bean.Bean;
import com.opensymphony.xwork2.ActionSupport;

public class Action extends ActionSupport{

 private static final long serialVersionUID = 1L;
 private Bean bean;
 
 
 public Bean getBean() {
  return bean;
 }
 public void setBean(Bean bean) {
  this.bean = bean;
 }



 public String sayHello()
 {
  return "success";
 }
}

This class has only one function sayHello() and it just returns a string success. It also contains an object of Bean class and its getter setters.
Bean.java

package com.ekiras.bean;

public class Bean {

 private String usrName;

 public String getUsrName() {
  return usrName;
 }

 public void setUsrName(String usrName) {
  this.usrName = usrName;
 }
 
 
}

This class contains

One member variables
1. usrName- it is used to store the user name
getter setters for member variable