Class PropertyConstraint.ByClass

  • All Implemented Interfaces:
    PropertyConstraint
    Enclosing interface:
    PropertyConstraint

    public static class PropertyConstraint.ByClass
    extends Object
    implements PropertyConstraint
    ByClass accepts a property value if it is an instance of a specific Java class.
    Since:
    1.3
    Author:
    Matthew Pocock Constrain a property to containing values of a particular class e.g. new ByClass(String.class) or new ByClass(Double) will ensure that the property is a String or a Double respecitvely.
    • Constructor Detail

      • ByClass

        public ByClass​(Class cl)
        Create a new ByClass instance.
        Parameters:
        cl - the Class that all properties must be assignable to
    • Method Detail

      • getPropertyClass

        public Class getPropertyClass()
        Get the Class used as the constraint.
        Returns:
        the Class all properties must be instances of
      • accept

        public boolean accept​(Object value)
        Description copied from interface: PropertyConstraint
        accept returns true if the value fulfills the constraint. Manually compare items with the PropertyConstraint. Node: this will ususaly be done for you in an AnnotationType instance Use for implementing accept() on AnnotatoinType
        Specified by:
        accept in interface PropertyConstraint
        Parameters:
        value - an Object to check.
        Returns:
        a boolean.
      • subConstraintOf

        public boolean subConstraintOf​(PropertyConstraint subConstraint)
        Description copied from interface: PropertyConstraint

        subConstraintOf returns true if the constraint is a sub-constraint.

        A pair of constraints super and sub are in a superConstraint/subConstraint relationship if every object accepted by sub is also accepted by super. To put it another way, if instanceOf was used as a set-membership indicator function over some set of objects, then the set produced by super would be a superset of that produced by sub.

        It is not expected that constraints will neccesarily maintain references to super/sub types. It will be more usual to infer this relationship by introspecting the constraints themselves. For example, PropertyConstraint.ByClass will infer subConstraintOf by looking at the possible class of all items matching subConstraint.

        Useful when attempting to compare two constraints to see if it is necisary to retain both. You may want to check the more general or the more specific constraint only.
        Specified by:
        subConstraintOf in interface PropertyConstraint
        Parameters:
        subConstraint - a PropertyConstraint to check.
        Returns:
        a boolean.