org.gcube.common.clients.delegates
Class DiscoveryDelegate<A,S>

java.lang.Object
  org.gcube.common.clients.delegates.AbstractDelegate<A,S,DiscoveryConfig<A,S>>
      org.gcube.common.clients.delegates.DiscoveryDelegate<A,S>

Type Parameters:

A - the type of service addresses

All Implemented Interfaces:

ProxyDelegate<S>

public class DiscoveryDelegate<A,S>
extends AbstractDelegate<A,S,DiscoveryConfig<A,S>>

A ProxyDelegate that discovers service endpoints.

The delegates attempt to make Calls to endpoints cached in an EndpointCache. If the calls fail, or the cache is empty, they execute a Query for endpoints and call the results in turn until the call succeeds or there are no more endpoints to call. If the call succeeds with one endpoint, the delegates cache the endpoint in the EndpointCache.

Author:

Fabio Simeoni

See Also:

Query, EndpointCache

Constructor Summary

DiscoveryDelegate(DiscoveryConfig<A,S> config)
Creates an instance with a ProxyPlugin, a Query, and an EndpointCache.

Method Summary

<V> V

make(Call<S,V> call) Makes a Call to a given service endpoint.

Methods inherited from class org.gcube.common.clients.delegates.AbstractDelegate

config, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

DiscoveryDelegate

public DiscoveryDelegate(DiscoveryConfig<A,S> config)

Creates an instance with a ProxyPlugin, a Query, and an EndpointCache.

Parameters:

plugin - the plugin

query - the query

cache - the cache

Method Detail

make

public <V> V make(Call<S,V> call)
       throws Exception

Description copied from interface: ProxyDelegate

Makes a Call to a given service endpoint.

Type Parameters:

V - the type of the value returned from the call

Parameters:

call - the call

Returns:

the value returned from the call

Throws:

Exception - if the call fails