Struts 2 Set Tag Example


In this tutorial, we are going to tell how to use Struts 2 set tag (<s:set />). The set tag assigns a value to a variable in a specified scope.

The scope is the following…

  • application – the value will be set in application scope.
  • session– the value will be set in session scope.
  • request – the value will be set in request scope.
  • page – the value will be set in page scope.
  • action – the value will be set in the request scope and Struts action context using the name as a key.

Note: The value of set tag can be property value or hard-coded.

Assigning the property value in set tag variable.

<s:set var="ws" value="country" />

Assigning the hard-coded value in set tag variable.

<s:set var="ws" value="%{'INDIA'}" />

In this example, we check the condition using a set tag variable, if the condition is true it will be going in IF block otherwise ELSE block.

Web.xml

Add Struts 2 filters in web.xml

web.xml
<filter>
	<filter-name>struts2</filter-name>
	<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
	<filter-name>struts2</filter-name>
	<url-pattern>/*</url-pattern>
</filter-mapping>

Action Class

The action class has a country property.

SetTagAction.java
package org.websparrow;

import com.opensymphony.xwork2.ActionSupport;

public class SetTagAction extends ActionSupport {

	private static final long serialVersionUID = 6971245991310816510L;
	String country = "";

	@Override
	public String execute() throws Exception {
		return "SUCCESS";
	}

	public String getCountry() {
		return country;
	}

	public void setCountry(String country) {
		this.country = country;
	}
}

JSP Page

On the JSP page, we assign the property value into the set tag variable and check the condition.

index.jsp
<%@taglib prefix="s" uri="/struts-tags"%>
<html>
<head>
<title>Struts 2 Set Tag Example</title>
</head>
<body>
	<h1>Struts 2 Set Tag Example</h1>

	<%-- 	<s:set var="ws" value="%{'INDIA'}" /> --%>

	<s:set var="ws" value="country" />

	<s:if test="%{#ws=='INDIA'}">

		<p>Hi, You are from INDIA.</p>

	</s:if>
	<s:else>

		<p>Sorry, You are not from INDIA.</p>

	</s:else>

</body>
</html>

Struts.xml

Mapping the action URL and class.

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>
	<package name="default" extends="struts-default">
		<action name="setTag" class="org.websparrow.SetTagAction">
			<result name="SUCCESS">/index.jsp</result>
		</action>
	</package>
</struts>

Output

Now all is set, to check whether is it working or not, deploy the application and use the below URL. If country==INDIA it will be going in IF block otherwise ELSE block.

URL- localhost:8083/Struts2SetTagExample/setTag?country=INDIA

Screen 1

Struts 2 Set Tag Example

Screen 2

Struts 2 Set Tag Example

Download Source Code – struts2-set-tag-example.zip


Similar Posts

About the Author

Websparrow
I like sharing my experiments and ideas with everyone by writing articles on the latest technological trends.