Java IoT Authors: Stackify Blog, Yeshim Deniz, Pat Romanski, Matt Lonstine, Glenda Sims

Related Topics: Java IoT

Java IoT: Article



If you are planning to deploy your database application on the Internet or Intranet, very soon you will need to deal with state management.' The stateless nature of Web architecture makes it radically different from the other (traditional) client-server architectures. The servers do not maintain any information on a client after the request is served. NetDynamics offers a solution for such problems. You can develop a fully object-oriented Web application in Java using the NetDynamics system. It supports server side Java for the generation of dynamic Web pages, application logic and database connectivity. It also addresses security, access control and flow control of the user in a Web application.

Installation and Configuration
Thanks to Installshield, installation is easy. The software requires about 20Mb of disk space. For development, it needs a §minimum of 32 Mb RAM on Windows 95/ NT3.51 and 48Mb on NT4.0. On UNIX, 50MB of hard disk and 64 Mb are RAM required. The installation requires HTTP servers. I had installations of Microsoft's Front Page Web Server and Netscape's Fasttrak. The Setup detected both the servers along with their port numbers. It allowed me to select HTTP server and an appropriate connectivity (CGI/NSAPI/ISAPI) to it. Then I could start the Application Server' without any hassle.

System Components, Architecture and Working
The NetDynamics solution is based on a three-tier architecture in which its application server, along with the HTTP server, forms a middle tier. The middle tier implements the business logic processing. The application server is responsible for session state management, automatic queuing, scheduling and load balancing. Since the server is always running, the Web request does not have to share the time overhead of starting and stopping it.

The HTTP server passes the HTTP request to the NetDynamics Application Server through a client connection (CC) interface. The CC can either be a lightweight CGI executable (20K) or you can use the Microsoft ISAPI runtime library or Netscape server API (NSAPI). The CC puts the request in a shared memory-based request queue. A Connection Processor (CP) monitors the queue, validates the access privileges and loads and executes the Java code corresponding to the project on a Java Virtual machine. For every connection, CP interacts with a Persistence Engine (PE) to verify the existence of the user session. For the existing user session, PE maintains the information related to the session and login privileges. The programmers can also store some data at the page level, user session level or global level for all projects. The CP puts a database-related request in another queue. The Data Servers monitor the request queue and interact with RDBMS/DBMS natively (for Oracle, Informix, Sybase) or using ODBC. NetDynamics 3.0, comes with a WebEXTEND module which enables DS to interact with enterprise applications like SAP and PeopleSoft. The DS establishes persistent connections with the database. These persistent connections enhance the performance. The DS then sends the database results to CP. Using this data, CP dynamically generates an HTML page as designed by an application programmer.

As an administrator, you can control the number of CPs and DS's on the application servers. Again, you can distribute application servers over multiple machines. This can make your system scalable and distributed, which I think is a pretty good architecture.

Session Management, Access Control and Flow Control
NetDynamics computes and encrypts a unique session ID to each session and stores it as a hidden field' on every page. It also allows you to store your own data at the page level, user session level or global (to all) level. This facility is very good for designing applications like shopping cart.

They also provide a good security mechanism. You can authenticate the users whenever they log into the application. You can select database tables, Java events or Gradient WebCrusader (third party software) to authenticate the user. It maintains an access privilege list at every page and verifies user access with the list.

Development Process
NetDynamics Studio is a GUI development environment for Rapid Application Development (RAD). If you have used any other visual development tool, you will find yourself on home ground. Using drag-and-drop facility, you can create page templates, data sources, data objects and security objects. You can also use wizards to create all of these objects. The wizards are very useful for creating most commonly required templates. With the page template wizard, you can create single or multiple pages (search, master-detailed or drill-down). Then, you can customize the pages by adding use interface elements like static text box, text box, list box, combo box and radio button. The HTML generator generates an HTML page template that you can customize to add client side Java applets, JavaScript or images. With the Inspector window, you can set the properties of each of these GUI objects. You can bind the display objects, such as text box or radio buttons, to columns of the data objects and you can automatically fill the list box or combo box with data from database tables. The data object itself is derived from single or multiple tables with SQL or stored procedure access. The studio automatically generates Java code for the page.

Java API
NetDynamics's Java API is one of the best Java implementations. It is a set of classes organized in different packages - namely CSpider (general), visual, database, session, access and util, for adding your business logic. All classes begin with the characters "CSp", which stands for Spider (the former name of NetDynamics). The company name has changed but it is still stuck to the classes. Today, this is very common. However, it is better not to use thecompany name for API classes and methods!

  • CSpider Package consists of a static class called CSpider and other high level classes like CSpProject, etc. CSpider consists of static methods to access all projects, pages and data objects while creating project-specific information (e.g. session time out).
  • Visual Package consists of all server side classes of the GUI objects that the end user sees. It includes CSpPage, which is a server side container class. CSpPage can contain GUI classes like CSpTextBox, CSPListBox, CSpButton, etc.
  • Database Package contains classes related to relational databases as SQL abstraction (select, insert, update, delete and all), stored procedure abstraction, transaction processing, database schema, etc. You might frequently use methods related to joining tables or adding where clauses, (addDynamicCriterion). Here, I should note that the database API offers a high level abstraction. NetDynamics developed this excellent package well before JDBC was available. Still, if someone needs to access low level database calls, it is yet another API.' I look forward to seeing that JDBC API, which is planned to become an integral part of the existing API.
  • Session Package contains classes that are wrappers over standard Java data types. These classes have serialization and deserialization methods that make them sessionable. You can create your own sessionable objects using these classes.
  • Access package is very important for access control and privileges. It contains classes for security table, user profile, privileges and page flow security.
  • Util Package contains general purpose classes for error logging, encryption, named lists, etc.

    The Java API seems to be very impressive. It is flexible and complex and you may need to allow a considerable learning time.

    NetDynamics has developed a complex system on a very strong foundation. It provides a user-friendly development tool and excellent Java API. Through its session management capability, it has bridged the gap between the HTTP server and database server. Its security model makes it more suitable for the Web. While deploying your application, it is worth considering using JIT compilers for better performance

  • More Stories By Khanderao Kand

    Khanderao Kand is a Lead Architect for Oracle Fusion Middleware at Oracle Corp. He is involved in the development of Oracle’s SOA Suite covering various Integration and BPM technologies including BPEL and ESB. He also provides Architectural consultancy for Oracle’s next generation Fusion Applications to architect their solutions around SOA and BPM. He has been involved in the development of various industry standards like BPEL 2.0, SCA-Assembly, SCA-BPEL etc. In his two decades of Software Development experience, he played various roles like an Enterprise Architect of Peopletools, an architect in CRM and others. Being a code slinger, he plays around with various emerging tools and technologies. Occasionally he writes in technical magazines like Java Developers Journal, Web Services Journal, SOA World etc. He also speaks at various conferences like Oracle Open World, JAX Conference, and Software Development Best Practices.

    Comments (0)

    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.

    @ThingsExpo Stories
    DX World EXPO, LLC, a Lighthouse Point, Florida-based startup trade show producer and the creator of "DXWorldEXPO® - Digital Transformation Conference & Expo" has announced its executive management team. The team is headed by Levent Selamoglu, who has been named CEO. "Now is the time for a truly global DX event, to bring together the leading minds from the technology world in a conversation about Digital Transformation," he said in making the announcement.
    "Space Monkey by Vivent Smart Home is a product that is a distributed cloud-based edge storage network. Vivent Smart Home, our parent company, is a smart home provider that places a lot of hard drives across homes in North America," explained JT Olds, Director of Engineering, and Brandon Crowfeather, Product Manager, at Vivint Smart Home, in this SYS-CON.tv interview at @ThingsExpo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
    SYS-CON Events announced today that Conference Guru has been named “Media Sponsor” of the 22nd International Cloud Expo, which will take place on June 5-7, 2018, at the Javits Center in New York, NY. A valuable conference experience generates new contacts, sales leads, potential strategic partners and potential investors; helps gather competitive intelligence and even provides inspiration for new products and services. Conference Guru works with conference organizers to pass great deals to gre...
    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 develop...
    In his Opening Keynote at 21st Cloud Expo, John Considine, General Manager of IBM Cloud Infrastructure, led attendees through the exciting evolution of the cloud. He looked at this major disruption from the perspective of technology, business models, and what this means for enterprises of all sizes. John Considine is General Manager of Cloud Infrastructure Services at IBM. In that role he is responsible for leading IBM’s public cloud infrastructure including strategy, development, and offering m...
    "Evatronix provides design services to companies that need to integrate the IoT technology in their products but they don't necessarily have the expertise, knowledge and design team to do so," explained Adam Morawiec, VP of Business Development at Evatronix, in this SYS-CON.tv interview at @ThingsExpo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
    To get the most out of their data, successful companies are not focusing on queries and data lakes, they are actively integrating analytics into their operations with a data-first application development approach. Real-time adjustments to improve revenues, reduce costs, or mitigate risk rely on applications that minimize latency on a variety of data sources. In his session at @BigDataExpo, Jack Norris, Senior Vice President, Data and Applications at MapR Technologies, reviewed best practices to ...
    Widespread fragmentation is stalling the growth of the IIoT and making it difficult for partners to work together. The number of software platforms, apps, hardware and connectivity standards is creating paralysis among businesses that are afraid of being locked into a solution. EdgeX Foundry is unifying the community around a common IoT edge framework and an ecosystem of interoperable components.
    Large industrial manufacturing organizations are adopting the agile principles of cloud software companies. The industrial manufacturing development process has not scaled over time. Now that design CAD teams are geographically distributed, centralizing their work is key. With large multi-gigabyte projects, outdated tools have stifled industrial team agility, time-to-market milestones, and impacted P&L stakeholders.
    "Akvelon is a software development company and we also provide consultancy services to folks who are looking to scale or accelerate their engineering roadmaps," explained Jeremiah Mothersell, Marketing Manager at Akvelon, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
    "IBM is really all in on blockchain. We take a look at sort of the history of blockchain ledger technologies. It started out with bitcoin, Ethereum, and IBM evaluated these particular blockchain technologies and found they were anonymous and permissionless and that many companies were looking for permissioned blockchain," stated René Bostic, Technical VP of the IBM Cloud Unit in North America, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Conventi...
    In his session at 21st Cloud Expo, Carl J. Levine, Senior Technical Evangelist for NS1, will objectively discuss how DNS is used to solve Digital Transformation challenges in large SaaS applications, CDNs, AdTech platforms, and other demanding use cases. Carl J. Levine is the Senior Technical Evangelist for NS1. A veteran of the Internet Infrastructure space, he has over a decade of experience with startups, networking protocols and Internet infrastructure, combined with the unique ability to it...
    22nd International Cloud Expo, taking place June 5-7, 2018, at the Javits Center in New York City, NY, and co-located with the 1st DXWorld Expo will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud ...
    "Cloud Academy is an enterprise training platform for the cloud, specifically public clouds. We offer guided learning experiences on AWS, Azure, Google Cloud and all the surrounding methodologies and technologies that you need to know and your teams need to know in order to leverage the full benefits of the cloud," explained Alex Brower, VP of Marketing at Cloud Academy, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clar...
    Gemini is Yahoo’s native and search advertising platform. To ensure the quality of a complex distributed system that spans multiple products and components and across various desktop websites and mobile app and web experiences – both Yahoo owned and operated and third-party syndication (supply), with complex interaction with more than a billion users and numerous advertisers globally (demand) – it becomes imperative to automate a set of end-to-end tests 24x7 to detect bugs and regression. In th...
    "MobiDev is a software development company and we do complex, custom software development for everybody from entrepreneurs to large enterprises," explained Alan Winters, U.S. Head of Business Development at MobiDev, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
    Coca-Cola’s Google powered digital signage system lays the groundwork for a more valuable connection between Coke and its customers. Digital signs pair software with high-resolution displays so that a message can be changed instantly based on what the operator wants to communicate or sell. In their Day 3 Keynote at 21st Cloud Expo, Greg Chambers, Global Group Director, Digital Innovation, Coca-Cola, and Vidya Nagarajan, a Senior Product Manager at Google, discussed how from store operations and ...
    "There's plenty of bandwidth out there but it's never in the right place. So what Cedexis does is uses data to work out the best pathways to get data from the origin to the person who wants to get it," explained Simon Jones, Evangelist and Head of Marketing at Cedexis, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
    SYS-CON Events announced today that CrowdReviews.com has been named “Media Sponsor” of SYS-CON's 22nd International Cloud Expo, which will take place on June 5–7, 2018, at the Javits Center in New York City, NY. CrowdReviews.com is a transparent online platform for determining which products and services are the best based on the opinion of the crowd. The crowd consists of Internet users that have experienced products and services first-hand and have an interest in letting other potential buye...
    SYS-CON Events announced today that Telecom Reseller has been named “Media Sponsor” of SYS-CON's 22nd International Cloud Expo, which will take place on June 5-7, 2018, at the Javits Center in New York, NY. Telecom Reseller reports on Unified Communications, UCaaS, BPaaS for enterprise and SMBs. They report extensively on both customer premises based solutions such as IP-PBX as well as cloud based and hosted platforms.