org.pdfbox.util

Class PDFTextStripper

Known Direct Subclasses:
PDFHighlighter, PDFText2HTML, PDFTextStripperByArea, PrintTextLocations

public class PDFTextStripper
extends PDFStreamEngine

This class will take a pdf document and strip out all of the text and ignore the formatting and such.
Version:
$Revision: 1.69 $
Author:
Ben Litchfield

Field Summary

protected Vector
charactersByArticle
The charactersByArticle is used to extract text by article divisions.
protected Writer
output
The stream to write the output to.

Constructor Summary

PDFTextStripper()
Instantiate a new PDFTextStripper object.
PDFTextStripper(Properties props)
Instantiate a new PDFTextStripper object.

Method Summary

protected void
endDocument(PDDocument pdf)
This method is available for subclasses of this class.
protected void
endPage(PDPage page)
End a page.
protected void
endParagraph()
End a paragraph.
protected void
flushText()
This will print the text to the output stream.
protected List
getCharactersByArticle()
Character strings are grouped by articles.
protected int
getCurrentPageNo()
Get the current page number that is being processed.
PDOutlineItem
getEndBookmark()
Get the bookmark where text extraction should end, inclusive.
int
getEndPage()
This will get the last page that will be extracted.
String
getLineSeparator()
This will get the line separator.
protected Writer
getOutput()
The output stream that is being written to.
String
getPageSeparator()
This will get the page separator.
PDOutlineItem
getStartBookmark()
Get the bookmark where text extraction should start, inclusive.
int
getStartPage()
This is the page that the text extraction will start on.
String
getText(COSDocument doc)
Deprecated.
String
getText(PDDocument doc)
This will return the text of a document.
String
getWordSeparator()
This will get the word separator.
protected void
processPage(PDPage page, COSStream content)
This will process the contents of a page.
protected void
processPages(List pages)
This will process all of the pages and the text that is in them.
void
setEndBookmark(PDOutlineItem aEndBookmark)
Set the bookmark where the text extraction should stop.
void
setEndPage(int endPageValue)
This will set the last page to be extracted by this class.
void
setLineSeparator(String separator)
Set the desired line separator for output text.
void
setPageSeparator(String separator)
Set the desired page separator for output text.
void
setShouldSeparateByBeads(boolean aShouldSeparateByBeads)
Set if the text stripper should group the text output by a list of beads.
void
setSortByPosition(boolean newSortByPosition)
The order of the text tokens in a PDF file may not be in the same as they appear visually on the screen.
void
setStartBookmark(PDOutlineItem aStartBookmark)
Set the bookmark where text extraction should start, inclusive.
void
setStartPage(int startPageValue)
This will set the first page to be extracted by this class.
void
setSuppressDuplicateOverlappingText(boolean suppressDuplicateOverlappingTextValue)
By default the text stripper will attempt to remove text that overlapps each other.
void
setWordSeparator(String separator)
Set the desired word separator for output text.
boolean
shouldSeparateByBeads()
This will tell if the text stripper should separate by beads.
boolean
shouldSortByPosition()
This will tell if the text stripper should sort the text tokens before writing to the stream.
boolean
shouldSuppressDuplicateOverlappingText()
protected void
showCharacter(TextPosition text)
This will show add a character to the list of characters to be printed to the text file.
protected void
startDocument(PDDocument pdf)
This method is available for subclasses of this class.
protected void
startPage(PDPage page)
Start a new page.
protected void
startParagraph()
Start a new paragraph.
protected void
writeCharacters(TextPosition text)
Write the string to the output stream.
void
writeText(COSDocument doc, Writer outputStream)
Deprecated.
void
writeText(PDDocument doc, Writer outputStream)
This will take a PDDocument and write the text of that document to the print writer.

Methods inherited from class org.pdfbox.util.PDFStreamEngine

getColorSpaces, getCurrentPage, getFonts, getGraphicsStack, getGraphicsState, getGraphicsStates, getResources, getTextLineMatrix, getTextMatrix, getXObjects, processOperator, processOperator, processStream, processSubStream, registerOperatorProcessor, resetEngine, setColorSpaces, setFonts, setGraphicsStack, setGraphicsState, setGraphicsStates, setTextLineMatrix, setTextMatrix, showCharacter, showString

Field Details

charactersByArticle

protected Vector charactersByArticle
The charactersByArticle is used to extract text by article divisions. For example a PDF that has two columns like a newspaper, we want to extract the first column and then the second column. In this example the PDF would have 2 beads(or articles), one for each column. The size of the charactersByArticle would be 5, because not all text on the screen will fall into one of the articles. The five divisions are shown below Text before first article first article text text between first article and second article second article text text after second article Most PDFs won't have any beads, so charactersByArticle will contain a single entry.

output

protected Writer output
The stream to write the output to.

Constructor Details

PDFTextStripper

public PDFTextStripper()
            throws IOException
Instantiate a new PDFTextStripper object. This object will load properties from Resources/PDFTextStripper.properties.

PDFTextStripper

public PDFTextStripper(Properties props)
            throws IOException
Instantiate a new PDFTextStripper object. Loading all of the operator mappings from the properties object that is passed in.
Parameters:
props - The properties containing the mapping of operators to PDFOperator classes.

Method Details

endDocument

protected void endDocument(PDDocument pdf)
            throws IOException
This method is available for subclasses of this class. It will be called after processing of the document finishes.
Parameters:
pdf - The PDF document that is being processed.

endPage

protected void endPage(PDPage page)
            throws IOException
End a page. Default implementation is to do nothing. Subclasses may provide additional information.
Parameters:
page - The page we are about to process.

endParagraph

protected void endParagraph()
            throws IOException
End a paragraph. Default implementation is to do nothing. Subclasses may provide additional information.

flushText

protected void flushText()
            throws IOException
This will print the text to the output stream.

getCharactersByArticle

protected List getCharactersByArticle()
Character strings are grouped by articles. It is quite common that there will only be a single article. This returns a List that contains List objects, the inner lists will contain TextPosition objects.
Returns:
A double List of TextPositions for all text strings on the page.

getCurrentPageNo

protected int getCurrentPageNo()
Get the current page number that is being processed.
Returns:
A 1 based number representing the current page.

getEndBookmark

public PDOutlineItem getEndBookmark()
Get the bookmark where text extraction should end, inclusive. Default is null.
Returns:
The ending bookmark.

getEndPage

public int getEndPage()
This will get the last page that will be extracted. This is inclusive, for example if a 5 page PDF an endPage value of 5 would extract the entire document, an end page of 2 would extract pages 1 and 2. This defaults to Integer.MAX_VALUE such that all pages of the pdf will be extracted.
Returns:
Value of property endPage.

getLineSeparator

public String getLineSeparator()
This will get the line separator.
Returns:
The desired line separator string.

getOutput

protected Writer getOutput()
The output stream that is being written to.
Returns:
The stream that output is being written to.

getPageSeparator

public String getPageSeparator()
This will get the page separator.
Returns:
The page separator string.

getStartBookmark

public PDOutlineItem getStartBookmark()
Get the bookmark where text extraction should start, inclusive. Default is null.
Returns:
The starting bookmark.

getStartPage

public int getStartPage()
This is the page that the text extraction will start on. The pages start at page 1. For example in a 5 page PDF document, if the start page is 1 then all pages will be extracted. If the start page is 4 then pages 4 and 5 will be extracted. The default value is 1.
Returns:
Value of property startPage.

getText

public String getText(COSDocument doc)
            throws IOException

Deprecated.

Parameters:
doc - The document to extract the text from.
Returns:
The document text.

getText

public String getText(PDDocument doc)
            throws IOException
This will return the text of a document. See writeText.
NOTE: The document must not be encrypted when coming into this method.
Parameters:
doc - The document to get the text from.
Returns:
The text of the PDF document.

getWordSeparator

public String getWordSeparator()
This will get the word separator.
Returns:
The desired word separator string.

processPage

protected void processPage(PDPage page,
                           COSStream content)
            throws IOException
This will process the contents of a page.
Parameters:
page - The page to process.
content - The contents of the page.

processPages

protected void processPages(List pages)
            throws IOException
This will process all of the pages and the text that is in them.
Parameters:
pages - The pages object in the document.

setEndBookmark

public void setEndBookmark(PDOutlineItem aEndBookmark)
Set the bookmark where the text extraction should stop.
Parameters:
aEndBookmark - The ending bookmark.

setEndPage

public void setEndPage(int endPageValue)
This will set the last page to be extracted by this class.
Parameters:
endPageValue - New value of property endPage.

setLineSeparator

public void setLineSeparator(String separator)
Set the desired line separator for output text. The line.separator system property is used if the line separator preference is not set explicitly using this method.
Parameters:
separator - The desired line separator string.

setPageSeparator

public void setPageSeparator(String separator)
Set the desired page separator for output text. The line.separator system property is used if the page separator preference is not set explicitly using this method.
Parameters:
separator - The desired page separator string.

setShouldSeparateByBeads

public void setShouldSeparateByBeads(boolean aShouldSeparateByBeads)
Set if the text stripper should group the text output by a list of beads. The default value is true!
Parameters:
aShouldSeparateByBeads - The new grouping of beads.

setSortByPosition

public void setSortByPosition(boolean newSortByPosition)
The order of the text tokens in a PDF file may not be in the same as they appear visually on the screen. For example, a PDF writer may write out all text by font, so all bold or larger text, then make a second pass and write out the normal text.
The default is to not sort by position.

A PDF writer could choose to write each character in a different order. By default PDFBox does not sort the text tokens before processing them due to performance reasons.
Parameters:
newSortByPosition - Tell PDFBox to sort the text positions.

setStartBookmark

public void setStartBookmark(PDOutlineItem aStartBookmark)
Set the bookmark where text extraction should start, inclusive.
Parameters:
aStartBookmark - The starting bookmark.

setStartPage

public void setStartPage(int startPageValue)
This will set the first page to be extracted by this class.
Parameters:
startPageValue - New value of property startPage.

setSuppressDuplicateOverlappingText

public void setSuppressDuplicateOverlappingText(boolean suppressDuplicateOverlappingTextValue)
By default the text stripper will attempt to remove text that overlapps each other. Word paints the same character several times in order to make it look bold. By setting this to false all text will be extracted, which means that certain sections will be duplicated, but better performance will be noticed.
Parameters:
suppressDuplicateOverlappingTextValue - The suppressDuplicateOverlappingText to set.

setWordSeparator

public void setWordSeparator(String separator)
Set the desired word separator for output text. The PDFBox text extraction algorithm will output a space character if there is enough space between two words. By default a space character is used. If you need and accurate count of characters that are found in a PDF document then you might want to set the word separator to the empty string.
Parameters:
separator - The desired page separator string.

shouldSeparateByBeads

public boolean shouldSeparateByBeads()
This will tell if the text stripper should separate by beads.
Returns:
If the text will be grouped by beads.

shouldSortByPosition

public boolean shouldSortByPosition()
This will tell if the text stripper should sort the text tokens before writing to the stream.
Returns:
true If the text tokens will be sorted before being written.

shouldSuppressDuplicateOverlappingText

public boolean shouldSuppressDuplicateOverlappingText()
Returns:
Returns the suppressDuplicateOverlappingText.

showCharacter

protected void showCharacter(TextPosition text)
This will show add a character to the list of characters to be printed to the text file.
Overrides:
showCharacter in interface PDFStreamEngine
Parameters:
text - The description of the character to display.

startDocument

protected void startDocument(PDDocument pdf)
            throws IOException
This method is available for subclasses of this class. It will be called before processing of the document start.
Parameters:
pdf - The PDF document that is being processed.

startPage

protected void startPage(PDPage page)
            throws IOException
Start a new page. Default implementation is to do nothing. Subclasses may provide additional information.
Parameters:
page - The page we are about to process.

startParagraph

protected void startParagraph()
            throws IOException
Start a new paragraph. Default implementation is to do nothing. Subclasses may provide additional information.

writeCharacters

protected void writeCharacters(TextPosition text)
            throws IOException
Write the string to the output stream.
Parameters:
text - The text to write to the stream.

writeText

public void writeText(COSDocument doc,
                      Writer outputStream)
            throws IOException

Deprecated.

Parameters:
doc - The document to extract the text.
outputStream - The stream to write the text to.

writeText

public void writeText(PDDocument doc,
                      Writer outputStream)
            throws IOException
This will take a PDDocument and write the text of that document to the print writer.
Parameters:
doc - The document to get the data from.
outputStream - The location to put the text.