Package com.itextpdf.kernel.pdf.canvas.parser.listener

Class RegexBasedLocationExtractionStrategy

java.lang.Object

com.itextpdf.kernel.pdf.canvas.parser.listener.RegexBasedLocationExtractionStrategy

All Implemented Interfaces:

IEventListener, ILocationExtractionStrategy

       public class RegexBasedLocationExtractionStrategy extends Object implements ILocationExtractionStrategy
      

This class is designed to search for the occurrences of a regular expression and return the resultant rectangles. Do note that this class holds all text locations and can't be used for processing multiple pages. If you want to extract text from several pages of pdf document you have to create a new instance of RegexBasedLocationExtractionStrategy for each page.

Here is an example of usage with new instance per each page: PdfDocument document = new PdfDocument(new PdfReader("...")); for (int i = 1; i <= document.getNumberOfPages(); ++i) { RegexBasedLocationExtractionStrategy extractionStrategy = new RegexBasedLocationExtractionStrategy(""); PdfCanvasProcessor processor = new PdfCanvasProcessor(extractionStrategy); processor.processPageContent(document.getPage(i)); for (IPdfTextLocation location : extractionStrategy.getResultantLocations()) { //process locations ... } }

Constructor Summary

Constructors

Constructor	Description
RegexBasedLocationExtractionStrategy(String regex)
RegexBasedLocationExtractionStrategy(Pattern pattern)

Method Summary

Modifier and Type	Method	Description
void	eventOccurred(IEventData data, EventType type)	Called when some event occurs during parsing a content stream.
Collection<IPdfTextLocation>	getResultantLocations()	Returns the Rectangles that have been processed so far.
Set<EventType>	getSupportedEvents()	Provides the set of event types this listener supports.
protected List<CharacterRenderInfo>	toCRI(TextRenderInfo tri)	Convert TextRenderInfo to CharacterRenderInfo This method is public and not final so that custom implementations can choose to override it.
protected List<Rectangle>	toRectangles(List<CharacterRenderInfo> cris)	Converts CharacterRenderInfo objects to Rectangles This method is protected and not final so that custom implementations can choose to override it.

Methods inherited from class java.lang.Object

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

Constructor Details

RegexBasedLocationExtractionStrategy

             public RegexBasedLocationExtractionStrategy
             (String regex)
            

RegexBasedLocationExtractionStrategy

             public RegexBasedLocationExtractionStrategy
             (Pattern pattern)
            

Method Details

getResultantLocations

             public Collection<IPdfTextLocation> getResultantLocations()
            

Returns the Rectangles that have been processed so far.

Specified by:

getResultantLocations in interface ILocationExtractionStrategy

Returns:

Collection<IPdfTextLocation> instance with the current resultant IPdfTextLocations

eventOccurred

             public void eventOccurred
             (IEventData data, EventType type)
            

Called when some event occurs during parsing a content stream.

Specified by:

eventOccurred in interface IEventListener

Parameters:

data - Combines the data required for processing corresponding event type.

type - Event type.

getSupportedEvents

             public Set<EventType> getSupportedEvents()
            

Provides the set of event types this listener supports. Returns null if all possible event types are supported.

Specified by:

getSupportedEvents in interface IEventListener

Returns:

Set of event types supported by this listener or null if all possible event types are supported.

toCRI

             protected List<CharacterRenderInfo> toCRI
             (TextRenderInfo tri)
            

Convert TextRenderInfo to CharacterRenderInfo This method is public and not final so that custom implementations can choose to override it. Other implementations of CharacterRenderInfo may choose to store different properties than merely the Rectangle describing the bounding box. E.g. a custom implementation might choose to store Color information as well, to better match the content surrounding the redaction Rectangle.

Parameters:

tri - TextRenderInfo object

Returns:

a list of CharacterRenderInfos which represents the passed TextRenderInfo ?

toRectangles

             protected List<Rectangle> toRectangles
             (List<CharacterRenderInfo> cris)
            

Converts CharacterRenderInfo objects to Rectangles This method is protected and not final so that custom implementations can choose to override it. E.g. other implementations may choose to add padding/margin to the Rectangles. This method also offers a convenient access point to the mapping of CharacterRenderInfo to Rectangle. This mapping enables (custom implementations) to match color of text in redacted Rectangles, or match color of background, by the mere virtue of offering access to the CharacterRenderInfo objects that generated the Rectangle.

Parameters:

cris - list of CharacterRenderInfo objects

Returns:

an array containing the elements of this list