Struts 2 - The url tags

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The url tag is responsible for generating URL strings. The advantage of this is that you can supply parameters to the tag. Let us go through an example to show the usage of url tag.

Create action classes:

package com.tutorialspoint.struts2;

public class HelloWorldAction{
   private String name;

   public String execute() throws Exception {
      return "success";
   }
   
   public String getName() {
      return name;
   }

   public void setName(String name) {
      this.name = name;
   }
}

Create views

Let us have HelloWorld.jsp with the following content:

<%@ page contentType="text/html; charset=UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<html>
<head>
<title>Hello World</title>
</head>
<body>
<s:url id="login" action="login" var="myurl">
	<s:param name="user">Zara</s:param>
</s:url>

<a href='<s:property value="#myurl"/>'>
<s:property value="#myurl"/></a>

</body>
</html>

Here we are generating a url link to the "login.action". We have given this url a name "myurl". This is so that we can reuse this url link in multiple places within the jsp file. We then supply the url with a parameter called user. The parameter value is actually appended to the query string as you can see from the output above.

The URL tag is mainly useful when you want to create a dynamic hyperlink based on a bean's property value.

Configuration Files

Your struts.xml should look like:

<?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.devMode" value="true" />
   <package name="helloaction" extends="struts-default">
      <action name="hello" 
            class="com.tutorialspoint.struts2.HelloWorldAction" 
            method="execute">
         <result name="success">/HelloWorld.jsp</result>
      </action>
   </package>
</struts>

Your web.xml should look like:

<?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>Struts 2</display-name>
   <welcome-file-list>
      <welcome-file>index.jsp</welcome-file>
   </welcome-file-list>
   <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>
</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/HelloWorldStruts2/hello.action. This will give you following screen:

Struts url tag


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