/*
*
* This file is part of the iText (R) project.
Copyright (c) 1998-2017 iText Group NV
* Authors: Bruno Lowagie, et al.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License version 3
* as published by the Free Software Foundation with the addition of the
* following permission added to Section 15 as permitted in Section 7(a):
* FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
* ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
* OF THIRD PARTY RIGHTS
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Affero General Public License for more details.
* You should have received a copy of the GNU Affero General Public License
* along with this program; if not, see http://www.gnu.org/licenses or write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA, 02110-1301 USA, or download the license from the following URL:
* http://itextpdf.com/terms-of-use/
*
* The interactive user interfaces in modified source and object code versions
* of this program must display Appropriate Legal Notices, as required under
* Section 5 of the GNU Affero General Public License.
*
* In accordance with Section 7(b) of the GNU Affero General Public License,
* a covered work must retain the producer line in every PDF that is created
* or manipulated using iText.
*
* You can be released from the requirements of the license by purchasing
* a commercial license. Buying such a license is mandatory as soon as you
* develop commercial activities involving the iText software without
* disclosing the source code of your own applications.
* These activities include: offering paid services to customers as an ASP,
* serving PDFs on the fly in a web application, shipping iText with a closed
* source product.
*
* For more information, please contact iText Software Corp. at this
* address: sales@itextpdf.com
*/
package com.itextpdf.text.pdf.util;
import com.itextpdf.text.pdf.PRIndirectReference;
import com.itextpdf.text.pdf.PdfArray;
import com.itextpdf.text.pdf.PdfDictionary;
import com.itextpdf.text.pdf.PdfName;
import com.itextpdf.text.pdf.PdfObject;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
/**
* This class can be used to count the number of bytes needed when copying
* pages from an existing PDF into a newly created PDF.
*/
public class PdfResourceCounter {
/** A map of the resources that are already taken into account */
protected Map<Integer, PdfObject> resources;
/**
* Creates a PdfResourceCounter instance to be used to count the resources
* needed for either a page (in this case pass a page dictionary) or the
* trailer (root and info dictionary) of a PDF file.
* @param object the object we want to examine
*/
public PdfResourceCounter(PdfObject object) {
resources = new HashMap<Integer, PdfObject>();
process(object);
}
/**
* Processes an object. If the object is indirect, it is added to the
* list of resources. If not, it is just processed.
* @param object the object to process
*/
protected final void process(PdfObject object) {
PRIndirectReference ref = object.getIndRef();
if (ref == null || resources.put(ref.getNumber(), object) == null) {
loopOver(object);
}
}
/**
* In case an object is an array, a dictionary or a stream,
* we need to loop over the entries and process them one by one.
* @param object the object to examine
*/
protected final void loopOver(PdfObject object) {
switch (object.type()) {
case PdfObject.ARRAY:
PdfArray array = (PdfArray)object;
for (int i = 0; i < array.size(); i++) {
process(array.getDirectObject(i));
}
break;
case PdfObject.DICTIONARY:
case PdfObject.STREAM:
PdfDictionary dict = (PdfDictionary)object;
if (dict.isPages()) break;
for (PdfName name : dict.getKeys()) {
process(dict.getDirectObject(name));
}
break;
}
}
/**
* Returns a map with the resources.
* @return the resources
*/
public Map<Integer, PdfObject> getResources() {
return resources;
}
/**
* Returns the resources needed for the object that was used to create
* this PdfResourceCounter. If you pass a Map with resources that were
* already used by other objects, these objects will not be taken into
* account.
* @param res the resources that can be excluded when counting the bytes
* @return the number of bytes needed for an object
* @throws java.io.IOException
*/
public long getLength(Map<Integer, PdfObject> res) throws IOException {
long length = 0;
PdfObject object;
for (int ref : resources.keySet()) {
if (res != null && res.containsKey(ref)) {
continue;
}
ByteArrayOutputStream baos = new ByteArrayOutputStream();
object = resources.get(ref);
object.toPdf(null, baos);
length += baos.size();
}
return length;
}
}