PATH Documentation > WebObjects 4.5 > EOAdaptor Reference

EOJoin

Inherits from: NSObject

Package: com.apple.yellow.eoaccess

Class Description

An EOJoin describes one source-destination attribute pair for an EORelationship. See the EORelationship class specification for more information and for examples.

Method Types

Constructors

EOJoin

Querying the join

destinationAttribute

isReciprocalToJoin

sourceAttribute

Constructors

EOJoin

public EOJoin( EOAttribute source, EOAttribute destination)

Creates and returns a new EOJoin with the given source and destination attributes. See the EORelationship class specification for an example of creating a relationship using EOJoins.

See Also: addJoin (EORelationship)

Instance Methods

destinationAttribute

public EOAttribute destinationAttribute()

Returns the destination ("right") attribute used by the join.

See Also: destinationAttributes ( EORelationship)

isReciprocalToJoin

public boolean isReciprocalToJoin(EOJoin otherJoin)

Returns true if this join's source attribute is equal to otherJoin's destination attribute and otherJoin's source attribute is equal to this join's destination attribute. This is known as a back-referencing join.

See Also: inverseRelationship ( EORelationship)

sourceAttribute

public EOAttribute sourceAttribute()

Returns the source ("left") attribute used by the join.

See Also: sourceAttributes ( EORelationship)