18.4 Evaluating Conventions

Before looking at providing runtime configuration based on conventions you first need to understand how to evaluate those conventions from a plugin. Every plugin has an implicit application variable which is an instance of the GrailsApplication interface.

The GrailsApplication interface provides methods to evaluate the conventions within the project and internally stores references to all artifact classes within your application.

Artifacts implement the GrailsClass interface, which represents a Grails resource such as a controller or a tag library. For example to get all GrailsClass instances you can do:

for (grailsClass in application.allClasses) {
    println grailsClass.name
}

GrailsApplication has a few "magic" properties to narrow the type of artefact you are interested in. For example to access controllers you can use:

for (controllerClass in application.controllerClasses) {
    println controllerClass.name
}

The dynamic method conventions are as follows:

• *Classes - Retrieves all the classes for a particular artefact name. For example application.controllerClasses.

• get*Class - Retrieves a named class for a particular artefact. For example application.getControllerClass("PersonController")

• is*Class - Returns true if the given class is of the given artefact type. For example application.isControllerClass(PersonController)

The GrailsClass interface has a number of useful methods that let you further evaluate and work with the conventions. These include:

• getPropertyValue - Gets the initial value of the given property on the class

• hasProperty - Returns true if the class has the specified property

• newInstance - Creates a new instance of this class.

• getName - Returns the logical name of the class in the application without the trailing convention part if applicable

• getShortName - Returns the short name of the class without package prefix

• getFullName - Returns the full name of the class in the application with the trailing convention part and with the package name

• getPropertyName - Returns the name of the class as a property name

• getLogicalPropertyName - Returns the logical property name of the class in the application without the trailing convention part if applicable

• getNaturalName - Returns the name of the property in natural terms (e.g. 'lastName' becomes 'Last Name')

• getPackageName - Returns the package name

For a full reference refer to the javadoc API.