guide/blueprints/example_yaml/entity-constraint-catalog.yaml

brooklyn.catalog:
  items:
  - id: entity-constraint-example
    itemType: entity
    name: Entity Config Example
    item:
      type: org.apache.brooklyn.entity.stock.BasicEntity
      brooklyn.parameters:
      - name: compulsoryExample
        type: string
        constraints:
        - required
      - name: addressExample
        type: string
        constraints:
        - regex: ^(?:[0-9]{1,3}\.){3}[0-9]{1,3}$
      - name: numberExample
        type: double
        constraints:
        - $brooklyn:object:
            type: org.apache.brooklyn.util.math.MathPredicates
            factoryMethod.name: greaterThan
            factoryMethod.args:
            - 0.0
        - $brooklyn:object:
            type: org.apache.brooklyn.util.math.MathPredicates
            factoryMethod.name: lessThan
            factoryMethod.args:
            - 256.0