{"id":71573,"date":"2017-12-20T13:00:42","date_gmt":"2017-12-20T11:00:42","guid":{"rendered":"https:\/\/www.javacodegeeks.com\/?p=71573"},"modified":"2017-12-19T10:55:11","modified_gmt":"2017-12-19T08:55:11","slug":"rapid-semat-application-development-apache-isis","status":"publish","type":"post","link":"https:\/\/www.javacodegeeks.com\/2017\/12\/rapid-semat-application-development-apache-isis.html","title":{"rendered":"Rapid SEMAT Application Development with Apache Isis"},"content":{"rendered":"

TL;DR <\/b>This post talks about a\u00a0SEMAT pet project<\/a> I created using Apache Isis and deployed to OpenShift Online here\u00a0http:\/\/semat.ofbizian.com<\/a><\/p>\n

Apache Isis<\/h3>\n

As a Java developer who is working primarily on backend systems, I\u00a0hate\u00a0<\/span>do not enjoy creating user interfaces and dealing with Javascript. Luckily, there are Java projects such as JSF (grrr), Apache Wicket, Vaadin that can help avoid Javascript altogether and still create functional user interfaces. But even with these projects, the developer has to think about and actively create the user interface from Java code. That is similar to writing your own SQL statements in the age of ORMs such as Hibernate – an activity we do only when OOTB ORM is not good enough for the use case. And that is exactly where\u00a0Apache Isis<\/a> fits in: given a domain model and mapping annotations, it generates the complete user interface at runtime. In a sense, Apache Isis is a OUIM (Object\/User Interface Mapping) framework for Java.<\/p>\n

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\nThere is much more to Apache Isis than only creating user interfaces, it is a full stack rapid application development framework focused on domain driven design. But rather than talking about it, let’s see a complete application created with Apache Isis.<\/p>\n

SEMAT Essence Kernel<\/h3>\n

To learn Apache Isis, I decided to implement the SEMAT model and deploy it to OpenShift Online asa\u00a0 Docker container. Simply said, SEMAT (Software Engineering Method and Theory) Essence Kernel is a\u00a0OMG Standard<\/a> that helps define among other things a framework for describing the state of software projects from multiple perspectives (called alphas).
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SEMAT Alpa States<\/figcaption><\/figure><\/p>\n

The idea is, that every project can be described in a generic way using the following seven alphas:<\/p>\n

Stakeholders, Opportunity, Requirements, Software System, Work, Team, Way-of-Working. And each Alpha can be in one or multiple states, for example, the
\nStakeholders<\/a> can be: Recognized, Represented, Involved, In Agreement, Satisfied, etc. In addition, each state has certain items to be satisfied before an Alpha can be transitioned to that state.

<\/div> <\/div><\/p>\n

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Stakeholders Alpha’s States<\/figcaption><\/figure><\/p>\n

As you can see, this is a pretty simple domain model with a state machine logic behid it.<\/p>\n

The Showcase Application<\/h3>\n

Enough said, to see how much Java I had to write for this application, check the\u00a0dom module<\/a> of the project on\u00a0github<\/a>. All of the other skeleton code is generated through a maven plugin and no user interface code is required. And here is a screenshot of the Project domain entity screen rendering:<\/p>\n

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Project view as Apache Wicket screen<\/figcaption><\/figure><\/p>\n

In addition to generating a user interface, Apache Isis will generate also a REST API using the same domain model. How cool is that.<\/p>\n

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SEMAT REST API generated from domain model<\/figcaption><\/figure><\/p>\n

And the beauty of all this is, that generating UI allows you quickly to iterate over the domain model, show it to the business owners to get feedback and contonue evolving the model.<\/p>\n

Some of the SEMAT Application Features implemented\/enabled<\/h2>\n