Use @AdditionalCriteria
to define parameterized views on data.
You can define additional criteria on entities or mapped superclass. When specified at the mapped superclass level, the additional criteria definition applies to all inheriting entities, unless those entities define their own additional criteria, in which case those defined for the mapped superclass are ignored.
Annotation Elements
Table 2-1 describes this annotation's elements.
Table 2-1 @AdditionalCriteria Annotation Elements
Attribute | Description | Default |
---|---|---|
|
(Required) The JPQL fragment to use as the additional criteria. |
Usage
Additional criteria can provide an additional filtering mechanism for queries. This filtering option, for example, allows you to use an existing additional JOIN
expression defined for the entity or mapped superclass and allows you to pass parameters to it.
Set additional criteria parameters through properties on the entity manager factory or on the entity manager. Properties set on the entity manager override identically named properties set on the entity manager factory. Properties must be set on an entity manager before executing a query. Do not change the properties for the lifespan of the entity manager.
Note: Additional criteria are not supported with native SQL queries. |
Examples
Specify additional criteria using the @AdditionalCriteria
annotation or the <additional-criteria>
element. The additional criteria definition supports any valid JPQL string and must use this
as an alias to form the additional criteria. For example:
@AdditionalCriteria("this.address.city IS NOT NULL")
Example 2-1 shows additional criteria defined for the entity Employee
and then shows the parameters for the additional criteria set on the entity manager.
Example 2-1 Using @AdditionalCriteria Annotation
Define additional criteria on Employee
, as follows:
package model; @AdditionalCriteria("this.company=:COMPANY") public class Employee { ... }
Set the property on the EntityManager
. This example returns all employees of MyCompany
.
entityManager.setProperty("COMPANY", "MyCompany");
Example 2-2 illustrates the same example as before, but uses the <additional-criteria>
element in the eclipselink-orm.xml
mapping file.
Example 2-2 Using <additional-criteria> XML
<additional-criteria> <criteria>this.address.city IS NOT NULL</criteria> </additional-criteria>
Uses for Additional Criteria
Uses for additional criteria include:
Multitenancy
In a multitenancy environment, tenants (users, clients, organizations, applications) can share database tables, but the views on the data are restricted so that tenants have access only to their own data. You can use additional criteria to configure such restrictions.
Note: In most cases, you use the |
Example 2-3 Multitenancy Example 1
The following example restricts the data for a Billing client, such as a billing application or billing organization:
@AdditionalCriteria("this.tenant = 'Billing'")
Example 2-4 Multitenancy Example 2
The following example could be used in an application used by multiple tenants at the same time. The additional criteria is defined as:
@AdditionalCriteria("this.tenant = :tenant")
When the tenant acquires its EntityManagerFactory
or EntityManager
, the persistence/entity manager property tenant is set to the name of the tenant acquiring it. For example,
Map properties = new HashMap(); properties.put("tenant", "ACME"); EntityManagerFactory emf = Persistence.createEntityManagerFactory(properties);
Or
Map properties = new HashMap(); properties.put("tenant", "ACME"); EntityManager em = factory.createEntityManager(properties);
Soft Delete
The following example filters data that is marked as deleted (but which still exists in the table) from a query:
@AdditionalCriteria("this.isDeleted = false")
Data History
The following example returns the current data from a query, thus filtering out any out-of-date data, for example data stored in a history table.
@AdditionalCriteria("this.endDate is null")
Note: EclipseLink also provides specific history support, via |
Temporal Filtering
The following example filters on a specific date:
@AdditionalCriteria("this.startDate <= :viewDate and this.endDate >= :viewDate")
Shared Table
For a shared table, there may be inheritance in the table but not in the object model. For example, a SavingsAccount
class may be mapped to an ACCOUNT
table, but the ACCOUNT
table contains both savings account data (SAVINGS
) and checking account (CHECKING
) data. You can use additional criteria to filter out the checking account data.
See Also
For more information, see: