Static Models

The idea of KlumDSL is centered around static data models.

What are static data models?

A static model is a collection of classes that fulfills a couple of constraints:

• Its instances are quasi readonly, meaning that they are not changed once they are created (which could be assured by making all fields immutable - KlumAST however takes a different approach)
• Its methods are side effect free, and mainly consist of getters, quasi getters and converters
• Static data models are usually rather tightly coupled, allowing to traverse in both directions
• additional functionality is provided using a Decorators and Adapters (which is the aim of another project of the KlumDSL suite: KlumWrap)
• To be useful, static data models should be strongly typed

How does KlumAST implement the static data model paradigm?

Since 0.98 and continuing to 1.0, KlumAST aspires to create SDMs by using the following techniques:

• setters and added methods, as well as lifecycle methods are moved to a special inner class that is only visible during apply and create methods. This means that all DSL features are readily available whenever a model instance is created, but they do not pollute the interface of the model for the client (in observance of the Interface Segregation Principle)
• Other methods changing the state of the model (for instance, pseudo setters) must be marked using the an annotation with the meta annotation @WriteAccess. These method will be moved to the RW class as well. Core annotations with write access are @Mutator for manual write access methods and the lifecycle methods @PostCreate, @PostApply, @PostTree and @AutoCreate.

Transient fields

Fields marked with @Field(FieldType.TRANSIENT) allow to add transient data to a model. This data can be changed at will and will not participate in checks for equality.