DalResultXMLFilter (Starjava VO API)

java.lang.Object
- org.xml.sax.helpers.XMLFilterImpl
- - uk.ac.starlink.vo.DalResultXMLFilter

```
public class DalResultXMLFilter
extends org.xml.sax.helpers.XMLFilterImpl
```
SAX filter which ignores any tables in a VOTable document, except those in a RESOURCE which has type="results". This is suitable for getting the basic table from the result of an SIA or SSA service. Under some circumstances the results can come with a large amount of non-result information (for instance massive numbers of small footprint tables from http://www.stecf.org/hst-vo/hst_ssa?), which can have a very serious impact on performance when trying to build a DOM. So if all you are interested in is the results table which the SIA/SSA protocol says has to be there, using this filter can save a lot of unnecessary processing.
In many cases, you can just use the getDalResultTable(uk.ac.starlink.votable.VOElementFactory, org.xml.sax.InputSource) utility method.

See Also:

Simple Spectral Access Protocol, Simple Image Access Protocol

Constructor Summary

Constructors
Constructor Description

DalResultXMLFilter(org.xml.sax.XMLReader parent, uk.ac.starlink.votable.Namespacing namespacing)
Constructor.

Constructors
Constructor	Description
`DalResultXMLFilter(org.xml.sax.XMLReader parent, uk.ac.starlink.votable.Namespacing namespacing)`	Constructor.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`characters(char[] ch, int start, int length)`
`void`	`endElement(java.lang.String namespaceURI, java.lang.String localName, java.lang.String qName)`
`void`	`endPrefixMapping(java.lang.String prefix)`
`static uk.ac.starlink.table.StarTable`	`getDalResultTable(uk.ac.starlink.votable.VOElementFactory vofact, org.xml.sax.InputSource inSrc)`	Utility method which can return the single results table from a DAL-type response.
`void`	`ignorableWhitespace(char[] ch, int start, int length)`
`static uk.ac.starlink.votable.VOElement`	`parseDalResult(uk.ac.starlink.votable.VOElementFactory vofact, org.xml.sax.InputSource inSrc)`	Utility method which uses an instance of this class to turn a SAX InputSource into a DOM.
`void`	`processingInstruction(java.lang.String target, java.lang.String data)`
`void`	`skippedEntity(java.lang.String name)`
`void`	`startElement(java.lang.String namespaceURI, java.lang.String localName, java.lang.String qName, org.xml.sax.Attributes atts)`
`void`	`startPrefixMapping(java.lang.String prefix, java.lang.String uri)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from class org.xml.sax.helpers.XMLFilterImpl
endDocument, error, fatalError, getContentHandler, getDTDHandler, getEntityResolver, getErrorHandler, getFeature, getParent, getProperty, notationDecl, parse, parse, resolveEntity, setContentHandler, setDocumentLocator, setDTDHandler, setEntityResolver, setErrorHandler, setFeature, setParent, setProperty, startDocument, unparsedEntityDecl, warning

Constructor Detail

DalResultXMLFilter

public DalResultXMLFilter(org.xml.sax.XMLReader parent,
                          uk.ac.starlink.votable.Namespacing namespacing)

Constructor.

Parameters:: parent - parent SAX reader; namespacing - VOTable namespacing policy to employ

Method Detail

startElement

public void startElement(java.lang.String namespaceURI,
                         java.lang.String localName,
                         java.lang.String qName,
                         org.xml.sax.Attributes atts)
                  throws org.xml.sax.SAXException

Overrides:: startElement in class org.xml.sax.helpers.XMLFilterImpl
Throws:: org.xml.sax.SAXException

endElement

public void endElement(java.lang.String namespaceURI,
                       java.lang.String localName,
                       java.lang.String qName)
                throws org.xml.sax.SAXException

Overrides:: endElement in class org.xml.sax.helpers.XMLFilterImpl
Throws:: org.xml.sax.SAXException

startPrefixMapping

public void startPrefixMapping(java.lang.String prefix,
                               java.lang.String uri)
                        throws org.xml.sax.SAXException

Overrides:: startPrefixMapping in class org.xml.sax.helpers.XMLFilterImpl
Throws:: org.xml.sax.SAXException

endPrefixMapping
```
public void endPrefixMapping(java.lang.String prefix)
                      throws org.xml.sax.SAXException
```
Overrides:

endPrefixMapping in class org.xml.sax.helpers.XMLFilterImpl

Throws:

org.xml.sax.SAXException

characters

public void characters(char[] ch,
                       int start,
                       int length)
                throws org.xml.sax.SAXException

Overrides:: characters in class org.xml.sax.helpers.XMLFilterImpl
Throws:: org.xml.sax.SAXException

ignorableWhitespace

public void ignorableWhitespace(char[] ch,
                                int start,
                                int length)
                         throws org.xml.sax.SAXException

Overrides:: ignorableWhitespace in class org.xml.sax.helpers.XMLFilterImpl
Throws:: org.xml.sax.SAXException

processingInstruction

public void processingInstruction(java.lang.String target,
                                  java.lang.String data)
                           throws org.xml.sax.SAXException

Overrides:: processingInstruction in class org.xml.sax.helpers.XMLFilterImpl
Throws:: org.xml.sax.SAXException

skippedEntity
```
public void skippedEntity(java.lang.String name)
                   throws org.xml.sax.SAXException
```
Overrides:

skippedEntity in class org.xml.sax.helpers.XMLFilterImpl

Throws:

org.xml.sax.SAXException

parseDalResult

public static uk.ac.starlink.votable.VOElement parseDalResult(uk.ac.starlink.votable.VOElementFactory vofact,
                                                              org.xml.sax.InputSource inSrc)
                                                       throws java.io.IOException

Utility method which uses an instance of this class to turn a SAX InputSource into a DOM. The DOM will lack non-results tables.

Parameters:: vofact - factory which can generate VOTable DOMs; inSrc - source of the SAX stream
Throws:: java.io.IOException

getDalResultTable
```
public static uk.ac.starlink.table.StarTable getDalResultTable(uk.ac.starlink.votable.VOElementFactory vofact,
                                                               org.xml.sax.InputSource inSrc)
                                                        throws java.io.IOException
```
Utility method which can return the single results table from a DAL-type response. This is the single table within the RESOURCE element marked with type="results", as described by the SIA and SSA standards. The QUERY_STATUS INFO element is checked; in case of ERROR, an exception is thrown.

Parameters:

vofact - factory which can generate VOTable DOMs

inSrc - source of the SAX stream

Returns:

result table, never null

Throws:

java.io.IOException - in case of error, including an ERROR-valued QUERY_STATUS in the response, or no suitable table found

Class DalResultXMLFilter

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from class org.xml.sax.helpers.XMLFilterImpl

Constructor Detail

DalResultXMLFilter

Method Detail

startElement

endElement

startPrefixMapping

endPrefixMapping

characters

ignorableWhitespace

processingInstruction

skippedEntity

parseDalResult

getDalResultTable