uk.ac.starlink.vo

Class RegTapRegistryQuery

java.lang.Object

uk.ac.starlink.vo.RegTapRegistryQuery

All Implemented Interfaces:

RegistryQuery

public class RegTapRegistryQuery
extends Object
implements RegistryQuery

Registry Query implementation that uses TAP to access a Relational Registry.

Since:

11 Apr 2014

Author:

Mark Taylor

See Also:

IVOA Registry Relational Schema

Field Summary

Fields

Modifier and Type	Field and Description
static ValueInfo	ADQL_INFO Description of metadata item describing query text.
static String	AIP_REG TAP base URL for GAVO registry hosted at AIP.
static String	ARI_REG TAP base URL for GAVO registry hosted at ARI Heidelberg.
static String	EUROVO_REG TAP base URL for Euro-VO registry, currently hosted at ESAC.
static String	GAVO_REG TAP base URL for high-availablity GAVO registry (DNS pointer).
static String	INAF_REG TAP base URL for INAF registry (not sure if this is permanent).
static String	PARIS_REG TAP base URL for registry hosted at ObsPM, synced with GAVO.
static String[]	REGISTRIES List of known registry TAP base URLs.
static ValueInfo	REGISTRY_INFO Description of metadata item describing registry location.
static String	STSCI_REG TAP base URL for STScI/VAO registry.

Constructor Summary

Constructors

Constructor and Description
RegTapRegistryQuery(TapService tapService, Ivoid[] standardIds, String adqlWhere) Constructs a query which will return RegResource lists for registry resource records with two optional restrictions: (a) restricted to a given service type, and (b) restricted by some free-form ADQL.

Method Summary

Modifier and Type	Method and Description
static String	getAdqlCondition(ResourceField field, String keyword, boolean hasSubjectsTable) Returns text that can be used as part of a WHERE clause to supply to this class that tests for a keyword in a given RR field.
DescribedValue[]	getMetadata() Returns a set of DescribedValue objects which characterise this query.
Iterator<RegResource>	getQueryIterator() Executes the query described by this object and returns an Iterator over RegResource objects.
RegResource[]	getQueryResources() Executes the query described by this object and returns the result as an array of RegResources.
URL	getRegistry() Returns the registry URL.
static String[]	getSearchableRegistries(TapService regtapService) Queries a given registry for searchable registries suitable for use with this class.
String	getText() Returns the query text.

Methods inherited from class java.lang.Object

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

Field Detail

GAVO_REG

public static final String GAVO_REG

TAP base URL for high-availablity GAVO registry (DNS pointer).

See Also:

Constant Field Values

ARI_REG

public static final String ARI_REG

TAP base URL for GAVO registry hosted at ARI Heidelberg.

See Also:

Constant Field Values

AIP_REG

public static final String AIP_REG

TAP base URL for GAVO registry hosted at AIP.

See Also:

Constant Field Values

PARIS_REG

public static final String PARIS_REG

TAP base URL for registry hosted at ObsPM, synced with GAVO.

See Also:

Constant Field Values

EUROVO_REG

public static final String EUROVO_REG

TAP base URL for Euro-VO registry, currently hosted at ESAC.

See Also:

Constant Field Values

STSCI_REG

public static final String STSCI_REG

TAP base URL for STScI/VAO registry.

See Also:

Constant Field Values

INAF_REG

public static final String INAF_REG

TAP base URL for INAF registry (not sure if this is permanent).

See Also:

Constant Field Values

REGISTRIES

public static final String[] REGISTRIES

List of known registry TAP base URLs.

REGISTRY_INFO

public static final ValueInfo REGISTRY_INFO

Description of metadata item describing registry location.

ADQL_INFO

public static final ValueInfo ADQL_INFO

Description of metadata item describing query text.

Constructor Detail

RegTapRegistryQuery

public RegTapRegistryQuery(TapService tapService,
                           Ivoid[] standardIds,
                           String adqlWhere)

Constructs a query which will return RegResource lists for registry resource records with two optional restrictions: (a) restricted to a given service type, and (b) restricted by some free-form ADQL. The supplied adqlWhere text has to be written with some knowledge of the internals of this class, for instance what columns are available.

Parameters:

tapService - TAP service hosting relational registry

standardIds - possible case-insensitive values for RR standard_id field, or null if not restricted by service

adqlWhere - text to be ANDed with existing ADQL WHERE clause, or null for no further restriction

Method Detail

getMetadata

public DescribedValue[] getMetadata()

Description copied from interface: RegistryQuery

Returns a set of DescribedValue objects which characterise this query. These would be suitable for use in the parameter list of a StarTable resulting from the execution of this query.

Specified by:

getMetadata in interface RegistryQuery

getRegistry

public URL getRegistry()

Description copied from interface: RegistryQuery

Returns the registry URL.

Specified by:

getRegistry in interface RegistryQuery

Returns:

url

getText

public String getText()

Description copied from interface: RegistryQuery

Returns the query text.

Specified by:

getText in interface RegistryQuery

Returns:

query

getQueryResources

public RegResource[] getQueryResources()
                                throws IOException

Description copied from interface: RegistryQuery

Executes the query described by this object and returns the result as an array of RegResources.

Specified by:

getQueryResources in interface RegistryQuery

Returns:

resource list

Throws:

IOException

getQueryIterator

public Iterator<RegResource> getQueryIterator()
                                       throws IOException

Description copied from interface: RegistryQuery

Executes the query described by this object and returns an Iterator over RegResource objects. Note that the iterator's next method may throw the unchecked exception RegistryQueryException with a cause indicating the underlying error in case of a registry access problem.

Specified by:

getQueryIterator in interface RegistryQuery

Returns:

iterator over RegResources

Throws:

IOException

getAdqlCondition

public static String getAdqlCondition(ResourceField field,
                                      String keyword,
                                      boolean hasSubjectsTable)

Returns text that can be used as part of a WHERE clause to supply to this class that tests for a keyword in a given RR field. The nature of the test (=, LIKE etc) depends on the field. If no suitable ADQL can be written, null is returned

Note that this code currently works by identifying known ResourceFields, so unknown ResourceFields will return null.

Parameters:

field - field whose content is to be tested

keyword - value to test against

hasSubjectsTable - true iff the rr.res_subject table is available for the query (hack; if not it assumes the res_subjects field is available)

Returns:

ADQL snippet that may be inserted into WHERE clause, or null if it can't be done

getSearchableRegistries

public static String[] getSearchableRegistries(TapService regtapService)
                                        throws IOException

Queries a given registry for searchable registries suitable for use with this class.

Parameters:

regtapService - TAP service description of bootstrap relational registry

Returns:

list of TAP base URLs for found relational registries

Throws:

IOException