/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.pdfbox.util;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Vector;
import org.apache.pdfbox.cos.COSStream;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.common.PDStream;
/**
* This will extract text from a specified region in the PDF.
*
* @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
* @version $Revision: 1.5 $
*/
public class PDFTextStripperByArea extends PDFTextStripper
{
private List<String> regions = new ArrayList<String>();
private Map<String,Rectangle2D> regionArea = new HashMap<String,Rectangle2D>();
private Map<String,Vector<ArrayList<TextPosition>>> regionCharacterList =
new HashMap<String,Vector<ArrayList<TextPosition>>>();
private Map<String,StringWriter> regionText = new HashMap<String,StringWriter>();
/**
* Constructor.
* @throws IOException If there is an error loading properties.
*/
public PDFTextStripperByArea() throws IOException
{
super();
setPageSeparator( "" );
}
/**
* Instantiate a new PDFTextStripperArea object. Loading all of the operator
* mappings from the properties object that is passed in. Does not convert
* the text to more encoding-specific output.
*
* @param props
* The properties containing the mapping of operators to
* PDFOperator classes.
*
* @throws IOException
* If there is an error reading the properties.
*/
public PDFTextStripperByArea(Properties props) throws IOException
{
super(props);
setPageSeparator("");
}
/**
* Instantiate a new PDFTextStripperArea object. This object will load
* properties from PDFTextStripper.properties and will apply
* encoding-specific conversions to the output text.
*
* @param encoding
* The encoding that the output will be written in.
* @throws IOException
* If there is an error reading the properties.
*/
public PDFTextStripperByArea(String encoding) throws IOException
{
super(encoding);
setPageSeparator("");
}
/**
* Add a new region to group text by.
*
* @param regionName The name of the region.
* @param rect The rectangle area to retrieve the text from.
*/
public void addRegion( String regionName, Rectangle2D rect )
{
regions.add( regionName );
regionArea.put( regionName, rect );
}
/**
* Get the list of regions that have been setup.
*
* @return A list of java.lang.String objects to identify the region names.
*/
public List<String> getRegions()
{
return regions;
}
/**
* Get the text for the region, this should be called after extractRegions().
*
* @param regionName The name of the region to get the text from.
* @return The text that was identified in that region.
*/
public String getTextForRegion( String regionName )
{
StringWriter text = regionText.get( regionName );
return text.toString();
}
/**
* Process the page to extract the region text.
*
* @param page The page to extract the regions from.
* @throws IOException If there is an error while extracting text.
*/
public void extractRegions( PDPage page ) throws IOException
{
Iterator<String> regionIter = regions.iterator();
while( regionIter.hasNext() )
{
setStartPage(getCurrentPageNo());
setEndPage(getCurrentPageNo());
//reset the stored text for the region so this class
//can be reused.
String regionName = regionIter.next();
Vector<ArrayList<TextPosition>> regionCharactersByArticle = new Vector<ArrayList<TextPosition>>();
regionCharactersByArticle.add( new ArrayList<TextPosition>() );
regionCharacterList.put( regionName, regionCharactersByArticle );
regionText.put( regionName, new StringWriter() );
}
PDStream contentStream = page.getContents();
if( contentStream != null )
{
COSStream contents = contentStream.getStream();
processPage( page, contents );
}
}
/**
* {@inheritDoc}
*/
protected void processTextPosition( TextPosition text )
{
Iterator<String> regionIter = regionArea.keySet().iterator();
while( regionIter.hasNext() )
{
String region = regionIter.next();
Rectangle2D rect = regionArea.get( region );
if( rect.contains( text.getX(), text.getY() ) )
{
charactersByArticle = (Vector)regionCharacterList.get( region );
super.processTextPosition( text );
}
}
}
/**
* This will print the processed page text to the output stream.
*
* @throws IOException If there is an error writing the text.
*/
protected void writePage() throws IOException
{
Iterator<String> regionIter = regionArea.keySet().iterator();
while( regionIter.hasNext() )
{
String region = regionIter.next();
charactersByArticle = (Vector)regionCharacterList.get( region );
output = regionText.get( region );
super.writePage();
}
}
}