Package org.wildfly.discovery.impl

Class AggregateDiscoveryProvider

java.lang.Object

org.wildfly.discovery.impl.AggregateDiscoveryProvider

All Implemented Interfaces:

DiscoveryProvider

public final class AggregateDiscoveryProvider
extends Object
implements DiscoveryProvider

A discovery provider which aggregates multiple other providers together. The aggregate request is complete when all of the delegate provider requests are complete.

Author:

David M. Lloyd

Field Summary

Fields inherited from interface org.wildfly.discovery.spi.DiscoveryProvider

EMPTY

Constructor Summary

Constructors

Constructor	Description
AggregateDiscoveryProvider(DiscoveryProvider[] delegates)	Construct a new instance.

Method Summary

Modifier and Type	Method	Description
DiscoveryRequest	discover(ServiceType serviceType, FilterSpec filterSpec, DiscoveryResult result)	Attempt to discover implementations of a service.
void	processMissingTarget(URI location, Exception cause)	This method is invoked on provider if the invocation using discovered URI was not successful.

Methods inherited from class java.lang.Object

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

Constructor Details

AggregateDiscoveryProvider

public AggregateDiscoveryProvider(DiscoveryProvider[] delegates)

Construct a new instance.

Parameters:

delegates - the array of delegates (must not be null)

Method Details

discover

public DiscoveryRequest discover(ServiceType serviceType,
 FilterSpec filterSpec,
 DiscoveryResult result)

Description copied from interface: DiscoveryProvider

Attempt to discover implementations of a service. Matches must be written to the DiscoveryResult.addMatch(ServiceURL) method on the result parameter as they are found. The DiscoveryResult.complete() method must be called when the discovery process is complete or has timed out or failed for any other reason, otherwise discovery clients may hang indefinitely.

The discovery process should be asynchronous if possible. In this case, this method should return as soon as possible in order to unblock the calling thread quickly and allow other discovery mechanisms to proceed. The discovery process will not be considered complete until the result's completion method is called, even if such a call comes from a different thread.

Specified by:

discover in interface DiscoveryProvider

Parameters:

serviceType - the service type to match

filterSpec - the service attribute filter expression, or null to return all matches

result - the discovery result

processMissingTarget

public void processMissingTarget(URI location,
 Exception cause)

Description copied from interface: DiscoveryProvider

This method is invoked on provider if the invocation using discovered URI was not successful. This method is supposed to be used by lazy discovery algorithms. By default, it is set to empty method so it could be skipped by providers implementing polling algorithms.

Specified by:

processMissingTarget in interface DiscoveryProvider

Parameters:

location - location on which invocations has failed

cause - the cause of the failure