com.oracle.common.base

Interface Associator

All Known Implementing Classes:

DefaultKeyAssociator, NaturalAssociator

public interface Associator

The Associator interface facilitates the creation of a very generic equivalence relation between different objects and allows to group them based on the equality of the "association key" object returned by the getAssociatedKey(java.lang.Object) method.

Author:

gg 2012.03.11

See Also:

Associated

Method Summary

Modifier and Type	Method and Description
Object	getAssociatedKey(Object o) Determine the host key (or base) object to which the specified object is associated.

Method Detail

getAssociatedKey

Object getAssociatedKey(Object o)

Determine the host key (or base) object to which the specified object is associated.

Note: It's expected that the returned object is suitable to be used as an immutable identity (e.g. a key in a Map).
Note 2: Circular associations are not permitted.

Parameters:

o - the object to obtain an association for

Returns:

the host key that for this object, or null if this object has no association