uk.ac.starlink.vo

Class TapCapabilitiesDoc

java.lang.Object

uk.ac.starlink.vo.TapCapabilitiesDoc

public class TapCapabilitiesDoc
extends Object

Encapsulates useful information found in the capabilities document describing a TAP service. The static method readCapabilities(java.net.URL) can construct an instance of this class by parsing a suitable XML document.

Since:

26 Sep 2018

Author:

Mark Taylor

Constructor Summary

Constructors

Constructor and Description
TapCapabilitiesDoc(TapCapability tapCapability, StdCapabilityInterface[] intfs) Constructor.

Method Summary

Modifier and Type	Method and Description
static URL	getCapabilitiesUrl(URL baseUrl) Provides the URL to use for the capabilities endpoint, given the TAP service base URL.
StdCapabilityInterface[]	getInterfaces() Returns a list of capability,interface pairs found associated with this capabilities document.
static StdCapabilityInterface[]	getInterfaces(Element capsEl) Extracts a list of zero or more standard interfaces from the capabilities element.
TapCapability	getTapCapability() Returns the object that describes the TAP services capabilities as defined by TAPRegExt.
static TapCapability	getTapCapability(Element capsEl) Extracts a TapCapability from the top-level capabilities element, in accordance with the TAPRegExt standard.
static TapCapabilitiesDoc	readCapabilities(URL capsUrl) Reads a TAP capabilities document from a given URL and returns a TapCapabilitiesDoc object based on it.

Methods inherited from class java.lang.Object

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

Constructor Detail

TapCapabilitiesDoc

public TapCapabilitiesDoc(TapCapability tapCapability,
                          StdCapabilityInterface[] intfs)

Constructor.

Parameters:

tapCapability - describes TAPRegExt information

intfs - enumerates all known capability+interface pairs

Method Detail

getTapCapability

public TapCapability getTapCapability()

Returns the object that describes the TAP services capabilities as defined by TAPRegExt.

Returns:

TAP-specific capability description, or null if none found

getInterfaces

public StdCapabilityInterface[] getInterfaces()

Returns a list of capability,interface pairs found associated with this capabilities document. Note this may include an entry associated with the TAPRegExt capability.

Returns:

array of zero or more capability/interface specifications

getCapabilitiesUrl

public static URL getCapabilitiesUrl(URL baseUrl)

Provides the URL to use for the capabilities endpoint, given the TAP service base URL. This method basically just adds "/capabilities" on the end of the URL string, but it takes care of inserting a slash when required etc.

Parameters:

baseUrl - service URL

Returns:

capabilities endpoint URL

readCapabilities

public static TapCapabilitiesDoc readCapabilities(URL capsUrl)
                                           throws IOException,
                                                  SAXException

Reads a TAP capabilities document from a given URL and returns a TapCapabilitiesDoc object based on it. If it looks like there's no suitable document there, an exception is thrown.

Parameters:

capsUrl - location of capabilities document

Returns:

capabilities object, not null

Throws:

IOException

SAXException

getTapCapability

public static TapCapability getTapCapability(Element capsEl)
                                      throws javax.xml.xpath.XPathExpressionException

Extracts a TapCapability from the top-level capabilities element, in accordance with the TAPRegExt standard.

Parameters:

capsEl - capabilities element

Throws:

javax.xml.xpath.XPathExpressionException

getInterfaces

public static StdCapabilityInterface[] getInterfaces(Element capsEl)

Extracts a list of zero or more standard interfaces from the capabilities element.

Parameters:

capsEl - capabilities element

Returns:

capability/interface objects