| FieldActivator | Interface for a field activator. | code | html |
| ValueStore | Interface for storing values associated to an identity constraint. | code | html |
| IdentityConstraint | Base class of Schema identity constraint. | code | html |
| Field | Schema identity constraint field. | code | html |
| Field.Matcher | Field matcher. | code | html |
| Field.XPath | Field XPath. | code | html |
| KeyRef | Schema key reference identity constraint. | code | html |
| Selector | Schema identity constraint selector. | code | html |
| Selector.Matcher | Selector matcher. | code | html |
| Selector.XPath | Schema identity constraint selector XPath expression. | code | html |
| UniqueOrKey | Schema unique or key identity constraint. | code | html |
| XPathMatcher | XPath matcher. | code | html |