ConstraintValidatorFactory deprecated

Uses a service container to create constraint validators.

A constraint validator should be tagged as "validator.constraint_validator" in the service container and include an "alias" attribute:

<service id="some_doctrine_validator">
    <argument type="service" id="doctrine.orm.some_entity_manager" />
    <tag name="validator.constraint_validator" alias="some_alias" />
</service>

A constraint may then return this alias in its validatedBy() method:

public function validatedBy()
{
    return 'some_alias';
}