Dyn Solutions » Grails

GrailsCertification.com is now online!

dyn — Tue, 01 Dec 2009 19:09:05 +0000

Our new site: www.grailscertification.com is now online!

In this site, users can test their knowledge of the Grails Web framework.

There are 5 types of certifications: rookie, junior groovy, groovy, guru and holy grail, each of them with different levels.

Users can also submit questions to collaborate with our question database. Our aim is to have the biggest Grails question database online!

What are you waiting for? Test your skills right now: www.grailscertification.com

Grails and EJB2.1 integration

dyn — Tue, 18 Aug 2009 13:09:07 +0000

If you are working on a Grails project and you want to use existing business logic from EJB2.1 inside your application, you can easily achive this using Spring.

The first step is to include the Beans you want to use, inside your conf/spring/resources.groovy file like this:

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beans = {
ejbJndi(org.springframework.jndi.JndiTemplate){
environment = [
"java.naming.factory.initial" : "org.jnp.interfaces.NamingContextFactory",
"java.naming.provider.url" : "jnp://localhost:1099"]
}

businessBean(org.springframework.ejb.access.SimpleRemoteStatelessSessionProxyFactoryBean){
jndiName = "EJBBusinessBean"
businessInterface = "com.my.ejb.EJBBusinessBean"
jndiTemplate = ref("ejbJndi")
}

personBean(org.springframework.ejb.access.SimpleRemoteStatelessSessionProxyFactoryBean){
jndiName = "EJBPerson"
businessInterface = "com.my.ejb.EJBPerson"
jndiTemplate = ref("ejbJndi")
}
}

Then you can use any of the defined Beans inside your services or controllers like this:

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class MyService {
def personBean //spring injects the bean automatically

def myMethod(){
personBean.list()
}
}

That’s it!
Just remember to include the required JAR files (the EJB jars and the jars required to connect to the container, for instance, JBoss)

Grails Tips Part I – Domain Classes

dyn — Tue, 09 Jun 2009 17:27:16 +0000

I have been working a lot with Grails lately and I have to say that I love it!

It has allowed me to create some great web applications in a very fast and reliable way. While developing these applications, I learned a lot of useful things that I would like to share to you. Today I’ll give you some tips regarding Domain Classes.

1) Date created & Last Updated

If you want Grails to handle the date in which an object is created and the last time it was updated, all you have to do is add the following attributes to your domain class:

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As easy as that! Grails will automatically set the value for this two attributes when an object is created and every time it is updated.

2) Field order

If you want Grails to generate the fields for the create, edit & show views in a particular order, just define that order on the constraints. If the attribute doesn’t require a specific constraint (such as maxSize, unique, nullable, etc), just put the attribute on the constraints and leave the constraint empty.

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static constraints = {
name()
address()
city(nullable:true, blank:true)
phone(nullable:true, blank:true)
mobile(nullable:true, blank:true)
email(email:true)
}

3) Unique by group

If you want an attribute on a domain class to be unique, but only grouped by another attribute, you can do it. In the following example, the company name will be unique only for companies from the same client:

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class Company {
Client client
String name
String address
static constraints = {
name(size:3..50, blank:false, unique:'client')
address()
}
}

4) Change database mapping for String attribute

Grails will map the String attributes on your domain class to varchar(255) by default. If you want a String attribute mapped to text, here’s how you do it:

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static mapping = {
columns{
attribute_name type:"text"
}
}

Stay tuned for more Grails tips!