Slice 3.0 introduces a simple validation mechanism which allows you to check if a model meets certain requirements or, in other words, is valid. Thanks to validation tag, a component whose model is not valid may not be displayed on a page.
Basic interfaces
The validation mechanism is based on two interfaces:
Validatable
If a class should be a subject to validation it should implement com.cognifide.slice.validation.api.Validatable. The interface introduces only one method: validate, which takes one argument: com.cognifide.slice.validation.api.ValidationResultBuilder. The argument allows you to define a validation messages of different levels. The types include:
- error
- warning
- information
If at least one message has been added, the object is considered invalid. If there is no message, the object is considered valid.
Validator
The actual validation of an object is performed by com.cognifide.slice.validation.api.Validator interface. It defines one method: validate, which takes Validatable object as an argument. In result it returns ValidationResult. ValidationResult should be used for reading a result of validation and validation messages.