uk.ac.starlink.registry
Class AbstractRegistryClient<R>

java.lang.Object
  uk.ac.starlink.registry.AbstractRegistryClient<R>

Direct Known Subclasses:

BasicRegistryClient

public abstract class AbstractRegistryClient<R>
extends Object

Can submit ADQL queries to a registry and return the result as a list of resources. This class uses custom SAX parsing of the SOAP response to ensure that even a large response (not uncommon) can be processed without large client-side resource usage. For this reason, no use is made of the maximum record limit options provided by RI 1.0; there's no client-side need for it.

Author:

Mark Taylor

See Also:

IVOA Registry Interfaces

Constructor Summary

AbstractRegistryClient(SoapClient soapClient)
Constructs a AbstractRegistryClient given a SOAP client.

Method Summary

protected abstract ContentHandler	createResourceHandler(ResourceSink<R> sink) Returns a SAX ContentHandler which can parse a VOResources element and feed items of some type R to a ResourceSink object.
URL	getEndpoint() Returns the SOAP endpoint this client talks to.
Iterator<R>	getResourceIterator(SoapRequest request) Returns an iterator over resources corresponding to a given SOAP request.
List<R>	getResourceList(SoapRequest request) Returns a list of resources corresponding to a given SOAP request.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractRegistryClient

public AbstractRegistryClient(SoapClient soapClient)

Constructs a AbstractRegistryClient given a SOAP client.

Parameters:

soapClient - SOAP client which talks to an RI-compliant registry service

Method Detail

createResourceHandler

protected abstract ContentHandler createResourceHandler(ResourceSink<R> sink)

Returns a SAX ContentHandler which can parse a VOResources element and feed items of some type R to a ResourceSink object. R presumably represents a resource.

Parameters:

sink - receiver of resource objects

Returns:

new resource handler

getEndpoint

public URL getEndpoint()

Returns the SOAP endpoint this client talks to.

Returns:

registry endpoint

getResourceList

public List<R> getResourceList(SoapRequest request)
                        throws IOException

Returns a list of resources corresponding to a given SOAP request. The list is the result of feeding the SOAP response to the handler created by createResourceHandler(uk.ac.starlink.registry.ResourceSink).

Parameters:

request - SOAP request

Returns:

list of resources

Throws:

IOException

getResourceIterator

public Iterator<R> getResourceIterator(SoapRequest request)
                                throws IOException

Returns an iterator over resources corresponding to a given SOAP request. The resources are the result of feeding the SOAP response to the handler created by createResourceHandler(uk.ac.starlink.registry.ResourceSink).

The iterator's next or hasNext method may throw a RegistryQueryException.

The writing thread will only read resources from the SAX response as they are read out by the thread iterating over this iterator, so memory used by this class remains very small regardless of the number of records processed.

Parameters:

request - SOAP request

Returns:

iterator over resources; its next method may throw a RegistryQueryException

Throws:

IOException