/*
* $Id: ContentOperator.java 4242 2010-01-02 23:22:20Z xlv $
*
* This file is part of the iText project.
* Copyright (c) 1998-2009 1T3XT BVBA
* Authors: Kevin Day, Bruno Lowagie, Paulo Soares, 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 1T3XT,
* 1T3XT 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,
* you 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.parser;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.ListIterator;
import com.itextpdf.text.pdf.PRIndirectReference;
import com.itextpdf.text.pdf.PRStream;
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 com.itextpdf.text.pdf.PdfReader;
/**
* @author kevin
* @since 5.0.1
*/
public class ContentByteUtils {
private ContentByteUtils() {
// TODO Auto-generated constructor stub
}
/**
* Gets the content bytes from a content object, which may be a reference
* a stream or an array.
* @param contentObject the object to read bytes from
* @return the content bytes
* @throws IOException
*/
public static byte[] getContentBytesFromContentObject(final PdfObject contentObject) throws IOException {
final byte[] result;
switch (contentObject.type())
{
case PdfObject.INDIRECT:
final PRIndirectReference ref = (PRIndirectReference) contentObject;
final PdfObject directObject = PdfReader.getPdfObject(ref);
result = getContentBytesFromContentObject(directObject);
break;
case PdfObject.STREAM:
final PRStream stream = (PRStream) PdfReader.getPdfObject(contentObject);
result = PdfReader.getStreamBytes(stream);
break;
case PdfObject.ARRAY:
// Stitch together all content before calling processContent(), because
// processContent() resets state.
final ByteArrayOutputStream allBytes = new ByteArrayOutputStream();
final PdfArray contentArray = (PdfArray) contentObject;
final ListIterator<PdfObject> iter = contentArray.listIterator();
while (iter.hasNext())
{
final PdfObject element = iter.next();
allBytes.write(getContentBytesFromContentObject(element));
}
result = allBytes.toByteArray();
break;
default:
final String msg = "Unable to handle Content of type " + contentObject.getClass();
throw new IllegalStateException(msg);
}
return result;
}
/**
* Gets the content bytes of a page from a reader
* @param reader the reader to get content bytes from
* @param pageNum the page number of page you want get the content stream from
* @return a byte array with the effective content stream of a page
* @throws IOException
* @since 5.0.1
*/
public static byte[] getContentBytesForPage(PdfReader reader, int pageNum) throws IOException {
final PdfDictionary pageDictionary = reader.getPageN(pageNum);
final PdfObject contentObject = pageDictionary.get(PdfName.CONTENTS);
if (contentObject == null)
return new byte[0];
final byte[] contentBytes = ContentByteUtils.getContentBytesFromContentObject(contentObject);
return contentBytes;
}
}