Cover by Burt Beckwith

Safari, the world’s most comprehensive technology and business learning platform.

Find the exact information you need to solve a problem on the fly, or go deeper to master the technologies and skills you need to succeed

Start Free Trial

No credit card required

O'Reilly logo

Chapter 6. Integration

Working with Java Enterprise Edition (JEE) techologies in Grails is very similar to using them in traditional Spring applications. For the most part, you can use them directly, writing classes in Java or reusing existing shared code and JAR files. Often it can be easier to take advantage of an existing Grails plugin that configures the necessary dependencies for you, and often adds convenience methods, services, or DSLs to hide some of the complexity and boilerplate.

Of course, like in Spring applications, you often have easier ways to implement features than using JEE techologies. GORM is a lot easier to use than JPA, Grails services behave much like EJB stateless session beans, and you can use services like EJB stateful session beans by setting their scope to “session” so each user gets a separate instance and the life cycle is automatically tied to HTTP session creation and destruction. Integrate whatever existing functionality you have, especially if it’s tested and working, because it often doesn’t help to rewrite for the sake of doing everything the “Grails way,” but when adding new functionality, be sure to see if there’s already a solution in Grails or in a plugin.

JMS

Messaging with the Java Message Service (JMS) is very straightforward in Grails. As with many technologies, “there’s a plugin for that”—in this case, the jms plugin. It doesn’t provide an implementation, just the core functionality, leaving the actual JMS implementation details to a provider. ...

Find the exact information you need to solve a problem on the fly, or go deeper to master the technologies and skills you need to succeed

Start Free Trial

No credit card required