uk.ac.ox.cs.diadem.oxpath.core.extraction

Class NewSimpleExtractor

java.lang.Object

uk.ac.ox.cs.diadem.oxpath.core.extraction.NewSimpleExtractor

All Implemented Interfaces:

Extractor, OXPathCache

public class NewSimpleExtractor
extends Object
implements Extractor

Extractor implementation. We assume all method calls(except the constructor) are called by a proxy object generated by OXPathExtractor. Therefore, we don't check if the same node has already been extracted (the memoizer does this for us).

Author:

AndrewJSel, Giovanni Grasso

Constructor Summary

Constructors

Constructor and Description
NewSimpleExtractor(IAbstractOutputHandler oh)

Method Summary

Modifier and Type	Method and Description
Boolean	clear(DOMDocument page) Clears all memoized data for the input DOMDocument.
void	endExtraction() Signals end of extraction
Integer	extractNode(DOMNode context, String label, Integer parent) Allows the extraction of the node specified by the pair (context,label) and returns a unique identifier (as an int) that uniquely identifies this extraction marker.
Integer	extractNode(DOMNode context, String label, Integer parent, String value) Allows the extraction of the node specified by the pair (context,label) and returns a unique identifier (as an int) that uniquely identifies this extraction marker.

Methods inherited from class java.lang.Object

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

Constructor Detail

NewSimpleExtractor

public NewSimpleExtractor(IAbstractOutputHandler oh)

Method Detail

extractNode

public Integer extractNode(DOMNode context,
                           String label,
                           Integer parent)
                    throws OXPathException

Allows the extraction of the node specified by the pair (context,label) and returns a unique identifier (as an int) that uniquely identifies this extraction marker. May be a previously occurring identifier if the (context,label) has already been extracted (via a call to this method with this object).

Specified by:

extractNode in interface Extractor

Parameters:

context - the context node in this label

label - the label of this node in the extraction marker

parent - the parent of the extraction node specified by (context,label)

Returns:

a unique identifier for this extraction (though by OXPath's merge semantics, this extraction node may have already been created - in this case, the previous identifier is reused)

Throws:

OXPathException - in case the parent of this node is inconsistent with a recurring node (one already created with a previous call to this method)

extractNode

public Integer extractNode(DOMNode context,
                           String label,
                           Integer parent,
                           String value)
                    throws OXPathException

Allows the extraction of the node specified by the pair (context,label) and returns a unique identifier (as an int) that uniquely identifies this extraction marker. May be a previously occurring identifier if the (context,label) has already been extracted (via a call to this method with this object).

Specified by:

extractNode in interface Extractor

Parameters:

context - the context node in this label

label - the label of this node in the extraction marker

parent - the parent of the extraction node specified by (context,label)

value - the value associated with this extraction node

Returns:

a unique identifier for this extraction (though by OXPath's merge semantics, this extraction node may have already been created - in this case, the previous identifier is reused)

Throws:

OXPathException - in case the parent of this node is inconsistent with a recurring node (one already created with a previous call to this method)

endExtraction

public void endExtraction()
                   throws OXPathException

Signals end of extraction

Specified by:

endExtraction in interface Extractor

Throws:

OXPathException

clear

public Boolean clear(DOMDocument page)

Clears all memoized data for the input DOMDocument. Will be overridden as long as a proxy object is used (should always be used for OXPath classes overridding this method).

Specified by:

clear in interface OXPathCache

Parameters:

page - DOMDocument we are removing all memoized results for, presumably because the page is being closed in PAAT