Welcome!

Wearables Authors: Elizabeth White, Pat Romanski, Liz McMillan, Peter Silva, Jason Bloomberg

Related Topics: Java IoT, Open Source Cloud, IoT User Interface, Apache

Java IoT: Article

OpenXava 4.5: Rapid Java Web Development

OpenXava allows you develop applications just by writing simple domain classes with Java or Groovy

OpenXava is a framework for Rapid Java Web Development, well-suited for business and database oriented applications.

OpenXava allows you develop applications just by writing simple domain classes with Java or Groovy. The user interface is generated automatically in runtime, without code generation.

OpenXava 4.5 has some new interesting features such as:

  • Support for all strategies of JPA inheritance mapping.
  • Data for list and collections is obtained via JPA, before JDBC was used.
  • Automated Business Logic (ABL) library added.
  • All new layout architecture (the code that paints the UI). It still in BETA but can be activated with layout.painter in xava.properties.

And many other useful new features and bug fixes.

Support for all strategies of JPA inheritance mapping

This feature has been demanded for long time by the community. Until now only single table per class hierarchy mapping strategy was supported, that is the case where all classes hierarchy is stored in the same table. Since OpenXava 4.5 you can also use joined and table per class mapping strategies.
That is, you can write some classes in this way:

@Entity
@Inheritance(strategy=InheritanceType.JOINED)
class Computer extends Identifiable {
String name
}

@Entity
class Tablet extends Computer {
int screenSize
}

In this case, you have a table for Computer with ID and NAME columns  and a table for Tablet with ID and SCREENSIZE columns. JPA will do a JOIN of the two table when needed.
Also you can write:

@Entity
@Inheritance(strategy=InheritanceType.TABLE_PER_CLASS)
class Shop extends Identifiable {
String name
}

@Entity
class InternetShop extends Shop {
String url
}

In this case, you have a table for Shop with ID and NAME column and another for InternetShop with ID, NAME and URL columns.
From now on OpenXava will generate a correct user interface for the above classes.

Data for list and collections is obtained via JPA

Until now OpenXava has used JDBC to get the data for list and collections. It was in this way for historical reasons, specially because the very first version of OpenXava used EJB 1.0 CMP entities for persistence and EJB CMP is too slow and rigid to implement the OpenXava list behavior, so we used JDBC. But now, JPA is rapid and flexible enough to be used for obtaining the list data, so we have written a new JPATabProvider to read the data of the list, and it is the one used by default. This allows us to support all the inheritance JPA types, but also opens many interesting posibilities for the future, such as using DataNucleus instead of Hibernate as JPA engine to access to non-relational databases.

Automated Business Logic (ABL) library added

The folk from the California startup Automated Business Logic have been working hard to integrate their library, ABL, in OpenXava. ABL allows you to define business logic declaratively using annotations. The wiki explains how to use ABL from OpenXava.

All new layout architecture (the code that paints the UI)

The people from SicFlex, a Dominican company that has developed a complete ERP with OpenXava, have developed a new render engine for OpenXava. This is the more important and complicated part of OpenXava. This new render engine will generate even more complex and beautiful user interfaces for OpenXava applications. It is still in beta and it's disabled by default, but you can activate it with the next entries in xava.properties:

# Layout parser calculate and prepare properties to be renderer.
# This is optional, by default OX uses org.openxava.render.DefaultLayoutParser
layout.parser=org.openxava.web.layout.DefaultLayoutParser

# Layout painter, render all properties in cell forms
# If a valid painter is defined here, view rendering is performed by it.
layout.painter=org.openxava.web.layout.DefaultLayoutPainter

And more

See changelog for the complete list of new features and fixes.

Download OpenXava 4.5 and try it

More Stories By Javier Paniza

Javier Paniza is the project lead for OpenXava project. He works as software developer at Gestión 400, a software company for public administration in Spain. He has been developing with Java Enterprise since 1998. Also he has been J2EE mentor for development teams in banking projects.

@ThingsExpo Stories
SYS-CON Events announced today that Ericsson has been named “Gold Sponsor” of SYS-CON's @ThingsExpo, which will take place on June 7-9, 2016, at the Javits Center in New York, New York. Ericsson is a world leader in the rapidly changing environment of communications technology – providing equipment, software and services to enable transformation through mobility. Some 40 percent of global mobile traffic runs through networks we have supplied. More than 1 billion subscribers around the world re...
There is an ever-growing explosion of new devices that are connected to the Internet using “cloud” solutions. This rapid growth is creating a massive new demand for efficient access to data. And it’s not just about connecting to that data anymore. This new demand is bringing new issues and challenges and it is important for companies to scale for the coming growth. And with that scaling comes the need for greater security, gathering and data analysis, storage, connectivity and, of course, the...
SYS-CON Events announced today that DatacenterDynamics has been named “Media Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY. DatacenterDynamics is a brand of DCD Group, a global B2B media and publishing company that develops products to help senior professionals in the world's most ICT dependent organizations make risk-based infrastructure and capacity decisions.
SYS-CON Events announced today that Peak 10, Inc., a national IT infrastructure and cloud services provider, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Peak 10 provides reliable, tailored data center and network services, cloud and managed services. Its solutions are designed to scale and adapt to customers’ changing business needs, enabling them to lower costs, improve performance and focus inter...
You think you know what’s in your data. But do you? Most organizations are now aware of the business intelligence represented by their data. Data science stands to take this to a level you never thought of – literally. The techniques of data science, when used with the capabilities of Big Data technologies, can make connections you had not yet imagined, helping you discover new insights and ask new questions of your data. In his session at @ThingsExpo, Sarbjit Sarkaria, data science team lead ...
So, you bought into the current machine learning craze and went on to collect millions/billions of records from this promising new data source. Now, what do you do with them? Too often, the abundance of data quickly turns into an abundance of problems. How do you extract that "magic essence" from your data without falling into the common pitfalls? In her session at @ThingsExpo, Natalia Ponomareva, Software Engineer at Google, will provide tips on how to be successful in large scale machine lear...
In his session at @ThingsExpo, Chris Klein, CEO and Co-founder of Rachio, will discuss next generation communities that are using IoT to create more sustainable, intelligent communities. One example is Sterling Ranch, a 10,000 home development that – with the help of Siemens – will integrate IoT technology into the community to provide residents with energy and water savings as well as intelligent security. Everything from stop lights to sprinkler systems to building infrastructures will run ef...
Whether your IoT service is connecting cars, homes, appliances, wearable, cameras or other devices, one question hangs in the balance – how do you actually make money from this service? The ability to turn your IoT service into profit requires the ability to create a monetization strategy that is flexible, scalable and working for you in real-time. It must be a transparent, smoothly implemented strategy that all stakeholders – from customers to the board – will be able to understand and comprehe...
Machine Learning helps make complex systems more efficient. By applying advanced Machine Learning techniques such as Cognitive Fingerprinting, wind project operators can utilize these tools to learn from collected data, detect regular patterns, and optimize their own operations. In his session at 18th Cloud Expo, Stuart Gillen, Director of Business Development at SparkCognition, will discuss how research has demonstrated the value of Machine Learning in delivering next generation analytics to im...
This is not a small hotel event. It is also not a big vendor party where politicians and entertainers are more important than real content. This is Cloud Expo, the world's longest-running conference and exhibition focused on Cloud Computing and all that it entails. If you want serious presentations and valuable insight about Cloud Computing for three straight days, then register now for Cloud Expo.
IoT device adoption is growing at staggering rates, and with it comes opportunity for developers to meet consumer demand for an ever more connected world. Wireless communication is the key part of the encompassing components of any IoT device. Wireless connectivity enhances the device utility at the expense of ease of use and deployment challenges. Since connectivity is fundamental for IoT device development, engineers must understand how to overcome the hurdles inherent in incorporating multipl...
The increasing popularity of the Internet of Things necessitates that our physical and cognitive relationship with wearable technology will change rapidly in the near future. This advent means logging has become a thing of the past. Before, it was on us to track our own data, but now that data is automatically available. What does this mean for mHealth and the "connected" body? In her session at @ThingsExpo, Lisa Calkins, CEO and co-founder of Amadeus Consulting, will discuss the impact of wea...
SYS-CON Events announced today that Stratoscale, the software company developing the next generation data center operating system, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. Stratoscale is revolutionizing the data center with a zero-to-cloud-in-minutes solution. With Stratoscale’s hardware-agnostic, Software Defined Data Center (SDDC) solution to store everything, run anything and scale everywhere...
Angular 2 is a complete re-write of the popular framework AngularJS. Programming in Angular 2 is greatly simplified – now it's a component-based well-performing framework. This immersive one-day workshop at 18th Cloud Expo, led by Yakov Fain, a Java Champion and a co-founder of the IT consultancy Farata Systems and the product company SuranceBay, will provide you with everything you wanted to know about Angular 2.
SYS-CON Events announced today that Men & Mice, the leading global provider of DNS, DHCP and IP address management overlay solutions, will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. The Men & Mice Suite overlay solution is already known for its powerful application in heterogeneous operating environments, enabling enterprises to scale without fuss. Building on a solid range of diverse platform support,...
You deployed your app with the Bluemix PaaS and it's gaining some serious traction, so it's time to make some tweaks. Did you design your application in a way that it can scale in the cloud? Were you even thinking about the cloud when you built the app? If not, chances are your app is going to break. Check out this webcast to learn various techniques for designing applications that will scale successfully in Bluemix, for the confidence you need to take your apps to the next level and beyond.
We’ve worked with dozens of early adopters across numerous industries and will debunk common misperceptions, which starts with understanding that many of the connected products we’ll use over the next 5 years are already products, they’re just not yet connected. With an IoT product, time-in-market provides much more essential feedback than ever before. Innovation comes from what you do with the data that the connected product provides in order to enhance the customer experience and optimize busi...
Increasing IoT connectivity is forcing enterprises to find elegant solutions to organize and visualize all incoming data from these connected devices with re-configurable dashboard widgets to effectively allow rapid decision-making for everything from immediate actions in tactical situations to strategic analysis and reporting. In his session at 18th Cloud Expo, Shikhir Singh, Senior Developer Relations Manager at Sencha, will discuss how to create HTML5 dashboards that interact with IoT devic...
Artificial Intelligence has the potential to massively disrupt IoT. In his session at 18th Cloud Expo, AJ Abdallat, CEO of Beyond AI, will discuss what the five main drivers are in Artificial Intelligence that could shape the future of the Internet of Things. AJ Abdallat is CEO of Beyond AI. He has over 20 years of management experience in the fields of artificial intelligence, sensors, instruments, devices and software for telecommunications, life sciences, environmental monitoring, process...
Digital payments using wearable devices such as smart watches, fitness trackers, and payment wristbands are an increasing area of focus for industry participants, and consumer acceptance from early trials and deployments has encouraged some of the biggest names in technology and banking to continue their push to drive growth in this nascent market. Wearable payment systems may utilize near field communication (NFC), radio frequency identification (RFID), or quick response (QR) codes and barcodes...