/*
* 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.List;
/**
* Split a document into several other documents.
*
* @author Mario Ivankovits
* @author Ben Litchfield
*/
public class Splitter
{
private PDDocument sourceDocument;
private PDDocument currentDestinationDocument;
private int splitLength = 1;
private int startPage = Integer.MIN_VALUE;
private int endPage = Integer.MAX_VALUE;
private List<PDDocument> destinationDocuments;
private 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
{
destinationDocuments = new ArrayList<PDDocument>();
sourceDocument = document;
processPages();
return destinationDocuments;
}
/**
* 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.");
}
splitLength = split;
}
/**
* This will set the start page.
*
* @param start the start page
*/
public void setStartPage(int start)
{
if(start <= 0)
{
throw new RuntimeException("Error split must be at least one page.");
}
startPage = start;
}
/**
* This will set the end page.
*
* @param end the end page
*/
public void setEndPage(int end)
{
if(end <= 0)
{
throw new RuntimeException("Error split must be at least one page.");
}
endPage = end;
}
/**
* Interface method to handle the start of the page processing.
*
* @throws IOException If an IO error occurs.
*/
private void processPages() throws IOException
{
for (int i = 0; i < sourceDocument.getNumberOfPages(); i++)
{
PDPage page = sourceDocument.getPage(i);
if (pageNumber + 1 >= startPage && pageNumber + 1 <= endPage)
{
processPage(page);
pageNumber++;
}
else
{
if (pageNumber > endPage)
{
break;
}
else
{
pageNumber++;
}
}
}
}
/**
* 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.
*/
private void createNewDocumentIfNecessary() throws IOException
{
if (splitAtPage(pageNumber) || currentDestinationDocument == null)
{
currentDestinationDocument = createNewDocument();
destinationDocuments.add(currentDestinationDocument);
}
}
/**
* Check if it is necessary to create a new document.
*
* @return true If a new document should be created.
*/
protected boolean splitAtPage(int pageNumber)
{
return pageNumber % splitLength == 0;
}
/**
* Create a new document to write the split contents to.
*
* @throws IOException If there is an problem creating the new document.
*/
protected PDDocument createNewDocument() throws IOException
{
PDDocument document = new PDDocument();
document.setDocumentInformation(getSourceDocument().getDocumentInformation());
document.getDocumentCatalog().setViewerPreferences(
getSourceDocument().getDocumentCatalog().getViewerPreferences());
return document;
}
/**
* 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 processPage(PDPage page) throws IOException
{
createNewDocumentIfNecessary();
PDPage imported = getDestinationDocument().importPage(page);
imported.setCropBox(page.getCropBox());
imported.setMediaBox(page.getMediaBox());
// only the resources of the page will be copied
imported.setResources(page.getResources());
imported.setRotation(page.getRotation());
}
/**
* The source PDF document.
*/
protected final PDDocument getSourceDocument()
{
return sourceDocument;
}
/**
* The source PDF document.
*/
protected final PDDocument getDestinationDocument()
{
return currentDestinationDocument;
}
}