Click here to close now.

Welcome!

Java Authors: Liz McMillan, Carmen Gonzalez, Pat Romanski, Blue Box Blog, Jnan Dash

Related Topics: Microservices Journal, Java, AJAX & REA, Web 2.0

Microservices Journal: Article

SOA World Expo: Enterprise Mashup Services

Part 1: Real-World SOA or Web 2.0 Novelties?

Since Web 2.0 kicked off scarcely a day goes by without a headline targeting mashups and their enablers, AJAX and Web Services, as the next hot Web technologies. Mashups are Web sites that integrate a variety of services (e.g., news feeds, weather reports, maps, and traffic conditions) in new and interesting ways. Just take a look at Zillow.com, which provides instant home valuations plotted as thumbtacks on a map (Figure 1), or HousingMaps.com, which marks listings from craigslist.org as captions on a map, and you'll get a clear picture of the power behind converging data sources.

Google Maps is often identified as the disruptive force that spawned the mashups movement. The popular mapping service is now the home of more than 600 mashups according to ProgrammableWeb.com. Why the hype? Google Maps provides a simple JavaScript API that makes geo-spatial data, a historically cost-prohibitive service, easily accessible to a broad audience with a variety of technical skills. Web 2.0-savvy developers are highly attracted to this simplified and accessible approach to SOA development because it no longer confines their Web site functionally to a user interface, but opens the site up to syndicate functionality and data. Thus a site's success is no longer based on traffic alone, but on the number of subscribers. The proliferation of these services is mind-boggling. ProgrammableWeb.com, a mashup-tracking site, has more than 300 registered services available to mix-and-match, and more than 1,100 registered mashups. Roughly 2.8 new sites are registered every day.

Despite the momentum behind mashups, corporate IT departments only consume a handful of the services used by the mashup crowd. Instead, businesses have constructed their own ecosystem of services in parallel to the Web 2.0 movement. The problem with corporate adoption of mashups is two-fold. First, the concept of mashups is often considered a social phenomenon or a grassroots effort tangential to enterprise software. Second, there's no clear path to integrate business services with those available on the Web. This second issue is due, in part, to the impedance mismatch between business services and mashup services. Mashup APIs are generally written in JavaScript, while services deployed to the enterprise are developed using Java or .NET technologies. Thus, both perception and technology define the barriers to corporations adopting an enterprise mashup strategy that incorporates external services such as Google Maps.

Despite these initial hurdles, the services and collaborative development style that mashups provide have created a buzz among enterprise software vendors. IBM recently announced a R&D effort to create an enterprise "mashup maker" - a tool that lets developers blend corporate services with external services, and rapidly assemble applications. More recently, Oracle announced the Oracle WebCenter Suite, which uses JSR-168/286 and WSRP 1.0/2.0 to mix-and-match corporate services using a combination of AJAX and Java portlets. The "mashup maker" and "mashups as a portal" are both interesting concepts and quite possibly the future of rapid business application development. In a later installment we will take a closer look at JSR-168/286 and WSRP 1.0/2.0 and how these standards can be used to create enterprise mashups that mix corporate services. Meanwhile, the aim of this article is to give application developers, specifically enterprise Java developers, the tools to build meaningful enterprise mashups that take advantage of the popular mashup services.

Today's Toolkit
Business services developed with Java technologies generally fall into one of four categories: Enterprise JavaBeans, Spring, POJOs, or Web Services. The problem is that mashup APIs are generally implemented with JavaScript. There are a few services such as Flickr that offer parallel APIs written in Java, .NET, and a number of other technologies. For sites that don't offer a Java API, developers are left to their own devices to bridge the integration gap between JavaScript and Java. Existing Web Services provide the most direct path to integration, and processing XML over XMLHttpRequests, though tedious, is a relatively established method of binding AJAX-enabled interfaces to Web Services. There are a number of JavaScript packages, such as the vcXMLRPC Library, that help simplify the handling of XML-RPC requests. However, integrating Java-centric applications built with Spring or Enterprise JavaBeans makes for a more interesting problem. The first solution that comes to mind is to expose an existing EJB or Spring application as a Web Service, a simple task given that both EJB 3.0 and Spring 2.0 support remote method invocations via a Web Service end-point (JSR 181). Despite the simplicity of creating such a Web Service, we are still presented with the cumbersome task of processing XML with JavaScript.

Java-to-AJAX libraries such as Direct Web Remoting (DWR) and JSON-RPC-Java offer a simple alternative by marshaling Java objects to JavaScript and letting JavaScript communicate directly with server-side Java objects (Figure 2). So developers can interact with Java objects as if they were client-side JavaScript objects, negating the need to work with XML. For instance, by using a Java-to-AJAX library we can expose operations performed by a session bean to an AJAX-enabled Web interface and then combine the outcomes of those operations with a mashup service. An added benefit of the servlet architecture used by DWR and JSON-RPC-Java is that both libraries can take advantage of the authentication and session management provided by Java EE 5. Despite the similarities shared by both DWR and JSON-RPC-Java, DWR has a few advantages, two of which are the ability to handle recursive object structures and its integration with a large number of other libraries and frameworks such as Spring, Struts, JSF, Rife, WebWorks, and Hibernate. Thus, the amalgamation of DWR, enterprise Java services, and JavaScript mashup APIs blends the flexibility and creativity behind Web 2.0 with the reliability, scalability, and security of the Java EE architecture without needing to manipulate XML documents.

Building an Enterprise Mashup
The example application referenced in this article uses the Java Persistence API (JPA), Google Maps, and DWR to create a simple customer address book application (Figure 3). The application plots customers by address on a map using Google Map's JavaScript API. Users can update an entry by selecting a marker on a map and editing associated values in a form. Changes are committed by clicking the update, remove, and create. All records are stored in an Oracle database and persisted using the JPA.

The application provides a simple end-to-end example that demonstrates one method of blending external mashup services with Java-centric business services. Note that this article does not provide an in-depth look at DWR, JPA, or Google Maps. Instead, the intention is to prove the simplicity of integration between these technologies and enable you, the reader, to build your own enterprise mashups that leverage popular JavaScript APIs like Google Maps. Please refer to the references included in this article for more information on DWR, JPA, and Google Maps.

Setting up the DWR servlet is simple and can easily be added to an existing application. To install the servlet, first put the DWR jar in the lib directory under the WEB-INF directory, and add the following lines to the web.xml descriptor:

<servlet>
   <display-name>DWR Servlet</display-name>
   <servlet-name>dwr-invoker</servlet-name>
   <servlet-class>uk.ltd.getahead.dwr.DWRServlet
   </servlet-class>
   <init-param>
     <param-name>debug</param-name>
     <param-value>true</param-value>
     </init-param>
  </servlet>
  <servlet-mapping>
     <servlet-name>dwr-invoker</servlet-name>
     <url-pattern>/dwr/*</url-pattern>
</servlet-mapping>

Next, DWR must be made aware of the Java objects that should be remotable as JavaScript interfaces. The Customers object is the single JPA entity used in the application and maps to a Customers table (Listing 1). A session façade named JavaServiceFacade is used to encapsulate operations on the Customers entity object (Listing 2). Both the JavaServiceFacade and Customers classes must be registered with DWR to interact with each object via JavaScript. To do so, simply create a dwr.xml file in the WEB-INF directory as follows:

<dwr>
   <allow>
   <create creator="new" javascript="JavaServiceFacade">
   <param name="class" value="com...JavaServiceFacade"/>
     <include method="queryCustomersFindAll"/>
     <include method="queryCustomersFindById"/>
     <include method="mergeCustomers"/>
     <include method="persistCustomers"/>
     <include method="removeCustomers"/>
   </create>
   <convert converter="bean" match="com...Customers"/>
    </allow>
</dwr>

The dwr.xml descriptor defines a subset of methods on the JavaServiceFacade object to expose and declares a JavaBean converter to marshal the Customers entity as a return value or method parameter. In this example, two query methods as well as the merge, persist, and remove operations contained in the JavaServiceFacade are exposed. Once the dwr.xml file is created, three JavaScript files must be imported in the JSP or HTML pages contained in the application. This enables the use of the JavaScript representation or remote interfaces of the JavaServiceFacade and Customers Java objects. The imports are as follows:

<script type='text/javascript'
src='../dwr/interface/JavaServiceFacade.js'></script>
<script type='text/javascript' src='../dwr/engine.js'></script>
<script type='text/javascript' src='../dwr/util.js'></script>

Note that only the JavaScript interface for the JavaServiceFacade is imported because it's the sole object that contains methods that are invoked explicitly. With the web.xml file configured, the dwr.xml file created, and all the necessary JavaScript files imported, the methods contained in the JavaServiceFacade are now accessible from a Web browser via JavaScript. To test the installation, open a Web browser and navigate to http://localhost:[port]/[nameofwebapp]/dwr. A screen should appear resembling that shown in Figure 4. Figure 5 shows all of the methods on the JavaServiceFacade that are accessible remotely.

The next step is to integrate the JavaScript interface for the JavaServiceFacade with the Google Maps API. To use the Google Maps API, an activation key is required. Visit www.google.com/apis/maps/signup.html to obtain a key. Keys are mapped to a unique URL so the key included in this article will only work with the source code provided. To use a key different from the one included in this example, simply add the following import statement to the top of your JSP page, replacing the key contained in the URL with the one obtained from the Google Maps registration page. The import below is required in the JSP page irrespective of the activation key used.

<script src="http://maps.google.com/maps?file=api&v=2&key=value"
type="text/javascript"></script>

With both DWR and Google Maps configured, DWR calls to the JPA façade and the Google Maps API can be integrated. A simple load function and a div tag, in this case named "map," are used to initialize the mapping UI. The load function is assigned to the onload attribute of the body tag in the HTML or JSP page. Note that if you're using Dojo you must use the frameworks dojo.addOnLoad function instead of the onload attribute. The load function used in the example application not only initializes the Google Maps API, but also calls the queryCustomersFindAll function defined in the JavaServiceFacade JavaScript interface to retrieve all the Customers objects. The JavaServiceFacade.queryCustomersFindAll function accepts a reference to another function as an argument. The argument handles the return value of the JavaServiceFacade.queryCustomersFindAll function as an asynchronous callback. In this case the callback handler is the processCustomers function, which processes the list of Customers returned by the JavaServiceFacade.queryCustomersFindAll function, plotting each Customers object on the map as a marker (Figure 6).

// Called on intial page load
function load() {
   if(GBrowserIsCompatible()){
     // Remotely call Java method
     // to extract all Customers
     JavaServiceFacade.queryCustomersFindAll(processCustomers);
     // Initalize map object
     map = new GMap2(document.getElementById("map"));
     // Add navigation controls to map
     map.addControl(new GSmallMapControl());
     map.addControl(new GMapTypeControl());
     // Initalize geocoder
     geocoder = new GClientGeocoder();
   }
}

// Plots an array of Customers on
var processCustomers =
   function(customers){
   // test if array is null
   if(customers != null &&
     typeof customers == 'object'){
     // iterator over array of customers
     for(var i=0;i < customers.length; i++){
       // plot each customer on the map
       addMarkerForCustomer( customers[i] );
       }
   } else {
     alert("Customer record is null!");
   }
   // Set map center and magnification
   map.setCenter(
     new GLatLng(37.4419, -122.1419), 9);
}

Plotting markers with Google Maps requires three simple steps. First, a geo-spatial point on the map is obtained by using the Google geocoder API. Second, a GMarker object representing the geo-spatial is created. Finally, the marker is added to the map at the given point by calling the addOverlay function on the current instance of the GMap2 object - the object that represents the map displayed in the UI. Below is the function used to plot a Customers object as a marker. In the example a geo-spatial point is generated with the address information provided by the Customers object. A helper function is used to create a new GMarker, which is then added to the map object with a call to the addOverlay function.

// Plots a customer on the map as a marker
function addMarkerForCustomer(customer){
...
   // create address string
   var address = customer.address + ...;
   // create point using geocoder
   geocoder.getLatLng(
     address,
     function(point) {
     ...
     // create marker
     var marker = createMarker(point, customer);
     // overlay marker on map
     map.addOverlay(marker);
     }
   );
...
}


More Stories By Ric Smith

Ric Smith is director, business and product strategy at Kaazing. provides Kaazing Corporation with a wealth of experience in product management and consulting for enterprise products and services. Prior to joining Kaazing, Ric was a principal product manager for Oracle's Fusion Middleware at Oracle's Headquarters in Redwood Shores, CA. In his role as a Principal Product Manager he was responsible for the evangelism and product direction of Oracle's AJAX and Java EE Web Tier offerings. Before joining the Fusion Middleware team, Ric worked for Oracle's consulting business as a principal consultant where he led development of mission-critical applications for prominent organizations within the defense/intelligence industry. In addition, Ric won consecutive awards for technical achievement for each year of his tenure as a consultant. Ric is a frequent speaker at international events and has written articles featured in leading industry publications such as Java Developer's Journal and AJAXWorld Magazine. He is also a representative to the OpenAjax Alliance and an honors graduate of the University of Arizona.

Comments (3) 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
EdwinVDS 10/31/08 06:25:43 AM EDT

I have started a poll on the subject of Enterprise Mashups here : http://www.micropoll.com/akira/TakeSurvey?id=1086551

S&S Media 02/01/07 06:11:27 AM EST

Webinale 07 - A Conference For the Next Generation Web
The Web is in motion! It's about conversations, interpersonal networking, personalization, and individualism. The need for immediacy, interactivity, and community, combined with new and light-weight technologies are changing the social structure of the Web. The Next Generation Web is about getting associated with openness, trust, authenticity and collaboration. Interactivity, new possibilities to connect, social software, usability, and community networking are fast catching up with users. This new buzz is generating fresh and exciting projects. The latest buzzword is Web 2.0, and the event for anyone seeking to stay on top of this buzz is Webinale 2.0!
More info at www.webinale.com

SOA News Desk 01/22/07 03:24:59 PM EST

Since Web 2.0 kicked off scarcely a day goes by without a headline targeting mashups and their enablers, AJAX and Web Services, as the next hot Web technologies. Mashups are Web sites that integrate a variety of services (e.g., news feeds, weather reports, maps, and traffic conditions) in new and interesting ways. Just take a look at Zillow.com, which provides instant home valuations plotted as thumbtacks on a map (Figure 1), or HousingMaps.com, which marks listings from craigslist.org as captions on a map, and you'll get a clear picture of the power behind converging data sources.

@ThingsExpo Stories
“In the past year we've seen a lot of stabilization of WebRTC. You can now use it in production with a far greater degree of certainty. A lot of the real developments in the past year have been in things like the data channel, which will enable a whole new type of application," explained Peter Dunkley, Technical Director at Acision, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
The best mobile applications are augmented by dedicated servers, the Internet and Cloud services. Mobile developers should focus on one thing: writing the next socially disruptive viral app. Thanks to the cloud, they can focus on the overall solution, not the underlying plumbing. From iOS to Android and Windows, developers can leverage cloud services to create a common cross-platform backend to persist user settings, app data, broadcast notifications, run jobs, etc. This session provides a high level technical overview of many cloud services available to mobile app developers, includi...
SYS-CON Events announced today that Ciqada will exhibit at SYS-CON's @ThingsExpo, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Ciqada™ makes it easy to connect your products to the Internet. By integrating key components - hardware, servers, dashboards, and mobile apps - into an easy-to-use, configurable system, your products can quickly and securely join the internet of things. With remote monitoring, control, and alert messaging capability, you will meet your customers' needs of tomorrow - today! Ciqada. Let your products take flight. For more inform...
Containers and microservices have become topics of intense interest throughout the cloud developer and enterprise IT communities. Accordingly, attendees at the upcoming 16th Cloud Expo at the Javits Center in New York June 9-11 will find fresh new content in a new track called PaaS | Containers & Microservices Containers are not being considered for the first time by the cloud community, but a current era of re-consideration has pushed them to the top of the cloud agenda. With the launch of Docker's initial release in March of 2013, interest was revved up several notches. Then late last...
Health care systems across the globe are under enormous strain, as facilities reach capacity and costs continue to rise. M2M and the Internet of Things have the potential to transform the industry through connected health solutions that can make care more efficient while reducing costs. In fact, Vodafone's annual M2M Barometer Report forecasts M2M applications rising to 57 percent in health care and life sciences by 2016. Lively is one of Vodafone's health care partners, whose solutions enable older adults to live independent lives while staying connected to loved ones. M2M will continue to gr...
Dave will share his insights on how Internet of Things for Enterprises are transforming and making more productive and efficient operations and maintenance (O&M) procedures in the cleantech industry and beyond. Speaker Bio: Dave Landa is chief operating officer of Cybozu Corp (kintone US). Based in the San Francisco Bay Area, Dave has been on the forefront of the Cloud revolution driving strategic business development on the executive teams of multiple leading Software as a Services (SaaS) application providers dating back to 2004. Cybozu's kintone.com is a leading global BYOA (Build Your O...
While not quite mainstream yet, WebRTC is starting to gain ground with Carriers, Enterprises and Independent Software Vendors (ISV’s) alike. WebRTC makes it easy for developers to add audio and video communications into their applications by using Web browsers as their platform. But like any market, every customer engagement has unique requirements, as well as constraints. And of course, one size does not fit all. In her session at WebRTC Summit, Dr. Natasha Tamaskar, Vice President, Head of Cloud and Mobile Strategy at GENBAND, will explore what is needed to take a real time communications ...
SYS-CON Media announced today that @WebRTCSummit Blog, the largest WebRTC resource in the world, has been launched. @WebRTCSummit Blog offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. @WebRTCSummit Blog can be bookmarked ▸ Here @WebRTCSummit conference site can be bookmarked ▸ Here
SYS-CON Events announced today that GENBAND, a leading developer of real time communications software solutions, has been named “Silver Sponsor” of SYS-CON's WebRTC Summit, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. The GENBAND team will be on hand to demonstrate their newest product, Kandy. Kandy is a communications Platform-as-a-Service (PaaS) that enables companies to seamlessly integrate more human communications into their Web and mobile applications - creating more engaging experiences for their customers and boosting collaboration and productiv...
SYS-CON Events announced today that BroadSoft, the leading global provider of Unified Communications and Collaboration (UCC) services to operators worldwide, has been named “Gold Sponsor” of SYS-CON's WebRTC Summit, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. BroadSoft is the leading provider of software and services that enable mobile, fixed-line and cable service providers to offer Unified Communications over their Internet Protocol networks. The Company’s core communications platform enables the delivery of a range of enterprise and consumer calling...
What exactly is a cognitive application? In her session at 16th Cloud Expo, Ashley Hathaway, Product Manager at IBM Watson, will look at the services being offered by the IBM Watson Developer Cloud and what that means for developers and Big Data. She'll explore how IBM Watson and its partnerships will continue to grow and help define what it means to be a cognitive service, as well as take a look at the offerings on Bluemix. She will also check out how Watson and the Alchemy API team up to offer disruptive APIs to developers.
The IoT Bootcamp is coming to Cloud Expo | @ThingsExpo on June 9-10 at the Javits Center in New York. Instructor. Registration is now available at http://iotbootcamp.sys-con.com/ Instructor Janakiram MSV previously taught the famously successful Multi-Cloud Bootcamp at Cloud Expo | @ThingsExpo in November in Santa Clara. Now he is expanding the focus to Janakiram is the founder and CTO of Get Cloud Ready Consulting, a niche Cloud Migration and Cloud Operations firm that recently got acquired by Aditi Technologies. He is a Microsoft Regional Director for Hyderabad, India, and one of the f...
The 17th International Cloud Expo has announced that its Call for Papers is open. 17th International Cloud Expo, to be held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, brings together Cloud Computing, APM, APIs, Microservices, Security, Big Data, Internet of Things, DevOps 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 opportunity. Submit your speaking proposal today!
So I guess we’ve officially entered a new era of lean and mean. I say this with the announcement of Ubuntu Snappy Core, “designed for lightweight cloud container hosts running Docker and for smart devices,” according to Canonical. “Snappy Ubuntu Core is the smallest Ubuntu available, designed for security and efficiency in devices or on the cloud.” This first version of Snappy Ubuntu Core features secure app containment and Docker 1.6 (1.5 in main release), is available on public clouds, and for ARM and x86 devices on several IoT boards. It’s a Trend! This announcement comes just as...
SYS-CON Media announced today that @ThingsExpo Blog launched with 7,788 original stories. @ThingsExpo Blog offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. @ThingsExpo Blog can be bookmarked. The Internet of Things (IoT) is the most profound change in personal and enterprise IT since the creation of the Worldwide Web more than 20 years ago.
The world's leading Cloud event, Cloud Expo has launched Microservices Journal on the SYS-CON.com portal, featuring over 19,000 original articles, news stories, features, and blog entries. DevOps Journal is focused on this critical enterprise IT topic in the world of cloud computing. Microservices Journal offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. Follow new article posts on Twitter at @MicroservicesE
SYS-CON Events announced today that robomq.io will exhibit at SYS-CON's @ThingsExpo, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. robomq.io is an interoperable and composable platform that connects any device to any application. It helps systems integrators and the solution providers build new and innovative products and service for industries requiring monitoring or intelligence from devices and sensors.
Wearable technology was dominant at this year’s International Consumer Electronics Show (CES) , and MWC was no exception to this trend. New versions of favorites, such as the Samsung Gear (three new products were released: the Gear 2, the Gear 2 Neo and the Gear Fit), shared the limelight with new wearables like Pebble Time Steel (the new premium version of the company’s previously released smartwatch) and the LG Watch Urbane. The most dramatic difference at MWC was an emphasis on presenting wearables as fashion accessories and moving away from the original clunky technology associated with t...
SYS-CON Events announced today that Litmus Automation will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Litmus Automation’s vision is to provide a solution for companies that are in a rush to embrace the disruptive Internet of Things technology and leverage it for real business challenges. Litmus Automation simplifies the complexity of connected devices applications with Loop, a secure and scalable cloud platform.
In 2015, 4.9 billion connected "things" will be in use. By 2020, Gartner forecasts this amount to be 25 billion, a 410 percent increase in just five years. How will businesses handle this rapid growth of data? Hadoop will continue to improve its technology to meet business demands, by enabling businesses to access/analyze data in real time, when and where they need it. Cloudera's Chief Technologist, Eli Collins, will discuss how Big Data is keeping up with today's data demands and how in the future, data and analytics will be pervasive, embedded into every workflow, application and infra...