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Can a Set<E> be a foreign key?

I have two classes, Cell and Character. Basically, the cell is like a room, and contains a variable (private Set<Long> cellHeldCharacters;) which holds the IDs of the characters within the cell (The IDs are Primary Keys). Can I use the Foreign Key annotation for the variable, or is it illegal
13

javax.persistence.SecondaryTable

. If no primary key join columns are specified, the join columns are assumed to reference the primary key columns of the primary table, and have the same names and types as the referenced primary key columns of the primary table. Example 1: Single secondary table with a single primary key column. @Entity
12

javax.persistence.GeneratedValue

) Provides for the specification of generation strategies for the values of primary keys. The GeneratedValue annotation may be applied to a primary key property or field of an entity or mapped superclass in ... to be supported for simple primary keys. Use of the GeneratedValue annotation is not supported for derived
12

javax.persistence.MapKey

the map key for associations of type java.util.Map when the map key is itself the primary key or ... other than the primary key is used as a map key then it is expected to have a uniqueness constraint ... ="department") @MapKey // map key is primary key public Map getEmployees
12

javax.persistence.MapsId

a ManyToOne or OneToOne relationship attribute that provides the mapping for an EmbeddedId primary key, an attribute within an EmbeddedId primary key, or a simple primary key of the parent entity ... corresponds. If the entity's primary key is of the same Java type as the primary key of the entity
12

javax.persistence.MapKeyJoinColumn

. Default (only applies if single join column is being used.) The same name as the primary key column ... ) Specifies a mapping to an entity that is a map key. The map key join column is in the collection table ... ) The name of the foreign key column for the map key. (Optional) The name of the foreign key column
12

javax.persistence.TableGenerator

get methods) Defines a primary key generator that may be referenced by name when a generator element ... on the primary key field or property. The scope of the generator name is global to the persistence ... of the primary key column in the table. (Optional) Name of the primary key column in the table
1

javax.jdo.annotations.Join

: "" Since: JDO 2.1 String generatePrimaryKey Generate or assume a primary key constraint exists on the column or columns associated with this join. Generate or assume a primary key constraint exists on the column ... assume a primary key constraint Default value: "" Since: JDO 2.1 String index The name of the index
1

javax.jdo.PersistenceManager

(primary key) JDO identity. If it is used for instances of classes using datastore identity ... javax.jdo Interface PersistenceManager PersistenceManager is the primary interface for JDO-aware ... .0 T getObjectById(Class<T> cls, Object key) Looks up the instance of the given type with the given
1

javax.jdo.spi.PersistenceCapable

identity, this method must be called on an instance of a persistence-capable class with its primary key ... is initialized with the value(s) of the primary key field(s) of the instance on which the method is called ... with the values of the primary key fields of the persistence-capable instance on which the method

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