Interface CollectionConstraint

All Known Implementing Classes:
CollectionConstraint.AllValuesIn, CollectionConstraint.And, CollectionConstraint.Contains, CollectionConstraint.Or

public interface CollectionConstraint
Used by AnnotationType to represent the constraint on the collection of values in a property-slot. CollectionConstraints usually use a PropertyConstraint to validate the individual elements. Use one or more of the built-in implementations to build new AnnotationTypes.
Since:
1.3
Author:
Thomas Down, Matthew Pocock
  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Interface
    Description
    static class 
    CollectionConstraint which validates all members of a Collection.
    static class 
    A collection constraint that accpepts collections iff they are accepted by both child constraints.
    static class 
    CollectionConstraint which validates a portion of a Collection.
    static class 
    A collection constraint that accepts items iff they are accepted by either child constraints.
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    ANY is a constraint which accepts a property for addition under all conditions.
    EMPTY is a constraint which only accepts the empty set.
    NONE is a constraint which accepts no value for a property under any condition.
  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    accept(Object values)
    accept returns true if the value fulfills the constraint.
    boolean
    subConstraintOf returns true if the constraint is a sub-constraint.
    boolean
    validateAddValue(Collection current, Object newValue)
    Return true iff the Collection formed by adding newValue to current would be accepted by this constraint.
    boolean
    Return true iff the Collection formed by removing newValue from current would be accepted by this constraint.
  • Field Details

    • ANY

      static final CollectionConstraint ANY
      ANY is a constraint which accepts a property for addition under all conditions. Whenever a CollectionConstraint is needed and you want to allow any value there
    • EMPTY

      EMPTY is a constraint which only accepts the empty set. Use this to indicate that a property must be undefined
    • NONE

      static final CollectionConstraint NONE
      NONE is a constraint which accepts no value for a property under any condition. This value indicates an impossible condition. It may be returned by methods such as AnnotationTools.intersection to indicate that NO values of a property (include undefined) are valid.
  • Method Details

    • accept

      boolean accept(Object values)
      accept returns true if the value fulfills the constraint.
      Parameters:
      values - a Collection to check.
      Returns:
      true if the values are acceptable powerUser Manually compare items with the CollectionConstraint. Node: this will ususaly be done for you in an AnnotationType instance
    • subConstraintOf

      boolean subConstraintOf(CollectionConstraint subConstraint)

      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, CollectionConstraint.ByClass will infer subConstraintOf by looking at the possible class of all items matching subConstraint.

      Parameters:
      subConstraint - a CollectionConstraint to check.
      Returns:
      a boolean. Usefull 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.
    • validateAddValue

      boolean validateAddValue(Collection current, Object newValue)
      Return true iff the Collection formed by adding newValue to current would be accepted by this constraint. Implementations may not assume that current is valid.
      Parameters:
      current - a Collection containing the current values
      newValue - the new value to add
      Returns:
      true if adding the new value will result in an acceptable property
    • validateRemoveValue

      boolean validateRemoveValue(Collection current, Object victim)
      Return true iff the Collection formed by removing newValue from current would be accepted by this constraint. Implementations may not assume that current is valid. However, current will already have been checked to ensure that it contains victim.
      Parameters:
      current - a Collection containing the current values
      victim - the value to remove
      Returns:
      true if removing the victim will result in an acceptable property value set