Welcome!

IoT User Interface Authors: Elizabeth White, John Basso, Kevin Jackson, Richard Hale, Liz McMillan

Related Topics: IoT User Interface, Java IoT

IoT User Interface: Article

Struts Validations Framework Using AJAX

Real-time data validation is one of the advantages of AJAX technology

Real-time data validation is one of the advantages of AJAX technology. By applying this technology, the struts validation framework will enrich the struts MVC and move the Web application closer to the desktop application.

The validation framework is used to validate fields. There are many ways to do validation on a Web application. It falls into two categories: server-side and client-side. A struts validation framework is one of the best frameworks for a Java-based Web application environment. It can configure the application using server-side validation and employ the error message that renders on the validation process invoked during the request processing time, or it can do client-side validation by using the JavaScript rendered on the requested page.

AJAX is a JavaScript technology that can asynchronously call the server and fetch the XML documents that are so popular lately. One of its uses is real-time data validation.

This article is concerned with enriching the existing struts validation framework with AJAX. A few components, such as a controller, have to be developed to select the validation framework and render the specific format message for the client side and a taglib to handle the error message rendering.

Prerequisites
You'll need a Windows system with Eclipse and the Tomcat application server. Make sure that the MSXML 3.0 ActiveX object is registered on your operating system. You'll also need the Struts library (http://struts.apache.org) and the JDOM library (www.jdom.org) for XML development (see Figure 1 and Figure 2).

Server-Side Scenario
StrustsActionServlet
We have to extend the class from org.apache.struts.action.ActionServlet to get the servletMapping variable that stores the information on how the extension will be formatted for action classes into the action path as a browser address. When the code is added, we have to configure web.xml as a Web application descriptor for the application server.

The web.xml configuration:

...
<servlet>
<servlet-name>action</servlet-name>
<servlet-class>net.sf.struts.servlet.StrutsActionServlet</servlet-class>
...
<servlet-mapping>
<servlet-name>action</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
...

The StrutsActionServlet Java code looks like this:

public class StrutsActionServlet extends the ActionServlet.
{
public String getServletMapping() {
return this.servletMapping;
}
}

AjaxValidationRequestProcessor
To support the existing Struts framework in the first step, we have to extend the RequestProcessor from the Struts package. We have to customize the request processor because we have to distinguish how we're going to do the validation - by using the existing Struts framework or the AJAX concept - and because we'll be making a contract between the server and client on how to interpret the message. In the message rendering we'll use the XML format, which is a good media messaging format. The definition of the XML format we'll apply is:

XML Format
<?xml version="1.0" encoding="UTF-8"?>
<message>
<identity name=messageAreaId>
     <description>
   MessageValue
</description>
</identity>
</message>

Description

  • Identity is the ID for the client JavaScript to acknowledge where the message will be placed.
  • Description is the result after the error message rendering from the server side.
First we need to get the servlet mapping configuration from the Web descriptor before moving onto the process mapping. After invoking the process, the application will prepare the instance of the form that inherits from the AjaxForm class. The processing manages AJAX validation and should check to ensure that the request from the client isn't using the struts validation framework. Other processes to perform during the request are process populate for collecting the information sent by the client into the action form, and process validation by using the method from the existing Struts validation framework that already exists in the parent class of AjaxValidationRequestProcessor (TilesRequestProcessor).

The validation process from the TilesRequestProcessor will invoke all the validation based on the struts validation framework and store the action errors into the request. What we need is to parse the action errors into pieces and generate the XML message validation that will be sent to the client side. Since we want to change the behavior of how the validation will be backed, the validation process should check the indicator of the validation framework being used (see Figure 3).

Generate the XML messages using JDOM as the processing engine. As shown in Figure 4, when the process validation is invoked and the condition of the validation framework is equal with the AJAX validation framework, the process will continue to populate the error message and build the XML message validation.

ErrorMessageHandler
This class handles the functionality of the XML message builder. This Java class will be building the XML message based on the identity and description property. After the caller invokes the buildXMLMessage, it will prepare the document and set the root element of the XML message. This class also has an addNextXMLMessage function to add more validation messages into the XML (see Listing 1).

The process method will set the content type of the response as "text/xml" and send the XML message as a string. The function of the process on the AjaxValidationRequestProcessor code will look like Listing 2.

The processValidation method will populate the action errors and construct the message based on the format contract of the XML for the client. The function of processValidation on AjaxValidationRequestProcessor code will be look like:

...
ActionErrors errors = (ActionErrors) request.getAttribute(Globals.ERROR_KEY);
Locale locale = (Locale) request.getAttribute(Globals.LOCALE_KEY);
generateXMLMessage(errors, identity, locale, sbXMLMessage);
...

Client-Side Scenario
Build the Taglib Component

  • AjaxJavaScriptLibraryTag: The taglib component to render the JavaScript function at the client side for basic XMLHTTP controller functions.
  • AjaxErrorHtmlRenderTag: The taglib component to render the area of the error message at the JSP page.
Configuring the Taglib Definition
After developing the taglib component, we need to configure the taglib tld file as shown in Listing 3.

Build JSP and Struts Configuration
To simulate the result of the validation processing, we first need to build the presentation layer by incorporating the taglib that we've build. In this case I'm trying to give an example validation by using the validation rules component from Struts, and also the validation that comes from the form itself. Prepare five textboxs under the JSP page. The first to fourth textbox are using the validation rule configuration, and the fifth textbox is using the validate process from the action form. Other than that, we also need a submit button to simulate that after submitting the form, the existing struts validation are still working without AJAX. The user interface will look like Figure 5.

More Stories By Sonny Hastomo

Sonny Hastomo is an IT architect at Sun Microsystems, Indonesia, for the telecommunication industry division. His currently is focusing on providing solution design, sizing, implementation, consulting services, and quality support to customers in their evaluation of their IT challenges.

Comments (9) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
hanan mahmoud 07/27/08 03:39:45 AM EDT

hi all
its realy great article and it helped me to understand validation in ajax better ,i just hope if any one have sample code about that topic because till now i don't know how to find one and also i don't know where to put the code samples in the article so plz help me

Commenter 05/17/06 01:40:52 PM EDT

I just need examples, and I can´t find it here. This article is weak.

SYS-CON Belgium News Desk 05/02/06 03:27:56 PM EDT

Struts Validations Framework Using AJAX
Real-time data validation is one of the advantages of AJAX technology. By applying this technology, the struts validation framework will enrich the struts MVC and move the Web application closer to the desktop application.

SYS-CON Australia News Desk 05/02/06 01:44:38 PM EDT

Real-time data validation is one of the advantages of AJAX technology. By applying this technology, the struts validation framework will enrich the struts MVC and move the Web application closer to the desktop application.

AJAX News Desk 05/02/06 12:55:46 PM EDT

AjaxWorld: Struts Validations Framework Using AJAX
Real-time data validation is one of the advantages of AJAX technology. By applying this technology, the struts validation framework will enrich the struts MVC and move the Web application closer to the desktop application.

Rajesh 05/02/06 12:17:24 PM EDT

The article was really nice.It would have been better if the source code was included.

Thanks

waikit 02/08/06 04:11:11 AM EST

can I have a sample code of the example shown in this article, please

regards

SYS-CON Australia News Desk 01/27/06 02:21:45 PM EST

Real-time data validation is one of the advantages of AJAX technology. By applying this technology, the struts validation framework will enrich the struts MVC and move the Web application closer to the desktop application.

Artem Vasiliev 01/26/06 06:18:56 AM EST

Sonnie, thank you for your article, it brings pretty interesting idea.
It would be great to see some sample application (with source code of course) implementing this approach. I even thought that I would find as a source code for the article, but seems like JDJ doesn't have such practice. Sonnie, can you provide that? It could be an archive hosted somewhere, here or at some free hosting, e.g. http://rapidshare.de/

@CloudExpo Stories
Cloud analytics is dramatically altering business intelligence. Some businesses will capitalize on these promising new technologies and gain key insights that’ll help them gain competitive advantage. And others won’t. Whether you’re a business leader, an IT manager, or an analyst, we want to help you and the people you need to influence with a free copy of “Cloud Analytics for Dummies,” the essential guide to this explosive new space for business intelligence.
Manufacturers are embracing the Industrial Internet the same way consumers are leveraging Fitbits – to improve overall health and wellness. Both can provide consistent measurement, visibility, and suggest performance improvements customized to help reach goals. Fitbit users can view real-time data and make adjustments to increase their activity. In his session at @ThingsExpo, Mark Bernardo Professional Services Leader, Americas, at GE Digital, discussed how leveraging the Industrial Internet a...
UpGuard has become a member of the Center for Internet Security (CIS), and will continue to help businesses expand visibility into their cyber risk by providing hardening benchmarks to all customers. By incorporating these benchmarks, UpGuard's CSTAR solution builds on its lead in providing the most complete assessment of both internal and external cyber risk. CIS benchmarks are a widely accepted set of hardening guidelines that have been publicly available for years. Numerous solutions exist t...
Amazon has gradually rolled out parts of its IoT offerings in the last year, but these are just the tip of the iceberg. In addition to optimizing their back-end AWS offerings, Amazon is laying the ground work to be a major force in IoT – especially in the connected home and office. Amazon is extending its reach by building on its dominant Cloud IoT platform, its Dash Button strategy, recently announced Replenishment Services, the Echo/Alexa voice recognition control platform, the 6-7 strategic...
In addition to all the benefits, IoT is also bringing new kind of customer experience challenges - cars that unlock themselves, thermostats turning houses into saunas and baby video monitors broadcasting over the internet. This list can only increase because while IoT services should be intuitive and simple to use, the delivery ecosystem is a myriad of potential problems as IoT explodes complexity. So finding a performance issue is like finding the proverbial needle in the haystack.
There will be new vendors providing applications, middleware, and connected devices to support the thriving IoT ecosystem. This essentially means that electronic device manufacturers will also be in the software business. Many will be new to building embedded software or robust software. This creates an increased importance on software quality, particularly within the Industrial Internet of Things where business-critical applications are becoming dependent on products controlled by software. Qua...
In his session at Cloud Expo, Robert Cohen, an economist and senior fellow at the Economic Strategy Institute, will provide economic scenarios that describe how the rapid adoption of software-defined everything including cloud services, SDDC and open networking will change GDP, industry growth, productivity and jobs. This session will also include a drill down for several industries such as finance, social media, cloud service providers and pharmaceuticals.
DevOps at Cloud Expo – being held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA – announces that its Call for Papers is open. Born out of proven success in agile development, cloud computing, and process automation, DevOps is a macro trend you cannot afford to miss. From showcase success stories from early adopters and web-scale businesses, DevOps is expanding to organizations of all sizes, including the world's largest enterprises – and delivering real results. Am...
The 19th International Cloud Expo has announced that its Call for Papers is open. Cloud Expo, to be held November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, brings together Cloud Computing, Big Data, Internet of Things, DevOps, Digital Transformation, Microservices and WebRTC to one location. With cloud computing driving a higher percentage of enterprise IT budgets every year, it becomes increasingly important to plant your flag in this fast-expanding business opportuni...
"We host and fully manage cloud data services, whether we store, the data, move the data, or run analytics on the data," stated Kamal Shannak, Senior Development Manager, Cloud Data Services, IBM, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
With the proliferation of both SQL and NoSQL databases, organizations can now target specific fit-for-purpose database tools for their different application needs regarding scalability, ease of use, ACID support, etc. Platform as a Service offerings make this even easier now, enabling developers to roll out their own database infrastructure in minutes with minimal management overhead. However, this same amount of flexibility also comes with the challenges of picking the right tool, on the right ...
IoT is rapidly changing the way enterprises are using data to improve business decision-making. In order to derive business value, organizations must unlock insights from the data gathered and then act on these. In their session at @ThingsExpo, Eric Hoffman, Vice President at EastBanc Technologies, and Peter Shashkin, Head of Development Department at EastBanc Technologies, discussed how one organization leveraged IoT, cloud technology and data analysis to improve customer experiences and effi...
The Internet of Things will challenge the status quo of how IT and development organizations operate. Or will it? Certainly the fog layer of IoT requires special insights about data ontology, security and transactional integrity. But the developmental challenges are the same: People, Process and Platform. In his session at @ThingsExpo, Craig Sproule, CEO of Metavine, demonstrated how to move beyond today's coding paradigm and shared the must-have mindsets for removing complexity from the develo...
SYS-CON Events announced today that MangoApps will exhibit at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. MangoApps provides modern company intranets and team collaboration software, allowing workers to stay connected and productive from anywhere in the world and from any device.
“delaPlex Software provides software outsourcing services. We have a hybrid model where we have onshore developers and project managers that we can place anywhere in the U.S. or in Europe,” explained Manish Sachdeva, CEO at delaPlex Software, in this SYS-CON.tv interview at @ThingsExpo, held June 7-9, 2016, at the Javits Center in New York City, NY.
Predictive analytics tools monitor, report, and troubleshoot in order to make proactive decisions about the health, performance, and utilization of storage. Most enterprises combine cloud and on-premise storage, resulting in blended environments of physical, virtual, cloud, and other platforms, which justifies more sophisticated storage analytics. In his session at 18th Cloud Expo, Peter McCallum, Vice President of Datacenter Solutions at FalconStor, discussed using predictive analytics to mon...
Keeping pace with advancements in software delivery processes and tooling is taxing even for the most proficient organizations. Point tools, platforms, open source and the increasing adoption of private and public cloud services requires strong engineering rigor – all in the face of developer demands to use the tools of choice. As Agile has settled in as a mainstream practice, now DevOps has emerged as the next wave to improve software delivery speed and output. To make DevOps work, organization...
The IoT is changing the way enterprises conduct business. In his session at @ThingsExpo, Eric Hoffman, Vice President at EastBanc Technologies, discussed how businesses can gain an edge over competitors by empowering consumers to take control through IoT. He cited examples such as a Washington, D.C.-based sports club that leveraged IoT and the cloud to develop a comprehensive booking system. He also highlighted how IoT can revitalize and restore outdated business models, making them profitable ...
SYS-CON Events announced today that Isomorphic Software will exhibit at DevOps Summit at 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Isomorphic Software provides the SmartClient HTML5/AJAX platform, the most advanced technology for building rich, cutting-edge enterprise web applications for desktop and mobile. SmartClient combines the productivity and performance of traditional desktop software with the simp...
"When you think about the data center today, there's constant evolution, The evolution of the data center and the needs of the consumer of technology change, and they change constantly," stated Matt Kalmenson, VP of Sales, Service and Cloud Providers at Veeam Software, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.