== Examples

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For example:

[source,java]
----
@DomainObject
public class Customer {
    public static class EmailSpecification extends AbstractSpecification<String> {
        public String satisfiesSafely(String proposed) {
            return EmailUtil.ensureValidEmail(proposed);    // <1>
        }
    }
    @javax.jdo.annotations.Column(allowsNull="true")                // <2>
    @Property(
        maxLength=30,
        mustSatisfy=EmailSpecification.class,
        regexPattern = "(\\w+\\.)*\\w+@(\\w+\\.)+[A-Za-z]+",
        regexPatternFlags=Pattern.CASE_INSENSITIVE
    )
    public String getEmailAddress() { /* ... */ }
    public void setEmailAddress(String emailAddress) { /* ... */ }
    ...
}
----
<1> the (fictitious) `EmailUtil.ensureValid(...)` (omitted for brevity) returns a string explaining if an email is invalid
<2> generally use instead of the `@Property#optionality` attribute





[TIP]
====
The annotation is one of a handful (others including xref:refguide:applib:index/annotation/Collection.adoc[@Collection], xref:refguide:applib:index/annotation/CollectionLayout.adoc[@CollectionLayout] and xref:refguide:applib:index/annotation/PropertyLayout.adoc[@PropertyLayout]) that can also be applied to the field, rather than the getter method.  This is specifically
so that boilerplate-busting tools such as link:https://projectlombok.org/[Project Lombok] can be used.
====


== Usage Notes
