org.microbean.settings

Class SourceOrderArbiter

java.lang.Object

org.microbean.settings.Arbiter

org.microbean.settings.SourceOrderArbiter

All Implemented Interfaces:

Serializable

@ApplicationScoped
public class SourceOrderArbiter
extends Arbiter

A simple Arbiter implementation that performs arbitration among Values by selecting the Value whose affiliated Source appears first in the Set of Sources supplied to the arbitrate(Set, String, Set, Collection) method.

Author:

Laird Nelson

See Also:

arbitrate(Set, String, Set, Collection), Arbiter, Serialized Form

Constructor Summary

Constructors

Constructor and Description
SourceOrderArbiter() Creates a new SourceOrderArbiter.

Method Summary

Modifier and Type	Method and Description
Value	arbitrate(Set<? extends Source> sources, String name, Set<? extends Annotation> qualifiers, Collection<? extends Value> values) Performs value arbitration by considering Values' affiliated Sources such that the Value whose Source appears earliest in the supplied sources Set will be selected.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SourceOrderArbiter

public SourceOrderArbiter()

Creates a new SourceOrderArbiter.

Method Detail

arbitrate

public Value arbitrate(Set<? extends Source> sources,
                       String name,
                       Set<? extends Annotation> qualifiers,
                       Collection<? extends Value> values)

Performs value arbitration by considering Values' affiliated Sources such that the Value whose Source appears earliest in the supplied sources Set will be selected.

Specified by:

arbitrate in class Arbiter

Parameters:

sources - the Set of Sources in effect during the current value acquisition operation; must not be null; must be unmodifiable; must be safe for concurrent read-only access by multiple threads

name - the name of the setting value being sought; must not be null

qualifiers - the Set of qualifier Annotations in effect during the current value acquisition operation; must not be null; must be unmodifiable; must be safe for concurrent read-only access by multiple threads

values - the Collection of Values acquired during the current value acquisition operation that were deemed to be indistinguishable; must not be null; must be unmodifiable; must be safe for concurrent read-only access by multiple threads

Returns:

the result of value arbitration as a single Value, or null if this SourceOrderArbiter could not select a single Value

Throws:

NullPointerException - if any parameter value is null

ArbitrationException - if there was a procedural problem with arbitration