/*
* 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 org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
/**
* Split a document into several other documents.
*
* @author Mario Ivankovits (mario@ops.co.at)
* @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
* @version $Revision: 1.7 $
*/
public class Splitter
{
/**
* The source PDF document.
*/
protected PDDocument pdfDocument;
/**
* The current PDF document that contains the splitted page.
*/
protected PDDocument currentDocument = null;
private int splitAtPage=1;
private List<PDDocument> newDocuments = null;
/**
* The current page number that we are processing, zero based.
*/
protected int pageNumber = 0;
/**
* This will take a document and split into several other documents.
*
* @param document The document to split.
*
* @return A list of all the split documents.
*
* @throws IOException If there is an IOError
*/
public List<PDDocument> split( PDDocument document ) throws IOException
{
newDocuments = new ArrayList<PDDocument>();
pdfDocument = document;
List pages = pdfDocument.getDocumentCatalog().getAllPages();
processPages(pages);
return newDocuments;
}
/**
* This will tell the splitting algorithm where to split the pages. The default
* is 1, so every page will become a new document. If it was to then each document would
* contain 2 pages. So it the source document had 5 pages it would split into
* 3 new documents, 2 documents containing 2 pages and 1 document containing one
* page.
*
* @param split The number of pages each split document should contain.
*/
public void setSplitAtPage( int split )
{
if( split <= 0 )
{
throw new RuntimeException( "Error split must be at least one page." );
}
splitAtPage = split;
}
/**
* This will return how many pages each split document will contain.
*
* @return The split parameter.
*/
public int getSplitAtPage()
{
return splitAtPage;
}
/**
* Interface method to handle the start of the page processing.
*
* @param pages The list of pages from the source document.
*
* @throws IOException If an IO error occurs.
*/
protected void processPages(List pages) throws IOException
{
Iterator iter = pages.iterator();
while( iter.hasNext() )
{
PDPage page = (PDPage)iter.next();
processNextPage( page );
}
}
/**
* Interface method, you can control where a document gets split by implementing
* this method. By default a split occurs at every page. If you wanted to split
* based on some complex logic then you could override this method. For example.
* <code>
* protected void createNewDocumentIfNecessary()
* {
* if( isPrime( pageNumber ) )
* {
* super.createNewDocumentIfNecessary();
* }
* }
* </code>
*
* @throws IOException If there is an error creating the new document.
*/
protected void createNewDocumentIfNecessary() throws IOException
{
if (isNewDocNecessary())
{
createNewDocument();
}
}
/**
* Check if it is necessary to create a new document.
*
* @return true If a new document should be created.
*/
protected boolean isNewDocNecessary()
{
return pageNumber % splitAtPage == 0 || currentDocument == null;
}
/**
* Create a new document to write the splitted contents to.
*
* @throws IOException If there is an problem creating the new document.
*/
protected void createNewDocument() throws IOException
{
currentDocument = new PDDocument();
currentDocument.setDocumentInformation(pdfDocument.getDocumentInformation());
currentDocument.getDocumentCatalog().setViewerPreferences(
pdfDocument.getDocumentCatalog().getViewerPreferences());
newDocuments.add(currentDocument);
}
/**
* Interface to start processing a new page.
*
* @param page The page that is about to get processed.
*
* @throws IOException If there is an error creating the new document.
*/
protected void processNextPage( PDPage page ) throws IOException
{
createNewDocumentIfNecessary();
PDPage imported = currentDocument.importPage( page );
imported.setCropBox( page.findCropBox() );
imported.setMediaBox( page.findMediaBox() );
// only the resources of the page will be copied
imported.setResources( page.getResources() );
imported.setRotation( page.findRotation() );
pageNumber++;
}
}